Journal articles: 'Interacting sprays'

1

Gai, Guodong, Abdellah Hadjadj, Sergey Kudriakov, Stephane Mimouni, and Olivier Thomine. "Numerical Study of Spray-Induced Turbulence Using Industrial Fire-Mitigation Nozzles." Energies 14, no. 4 (February 20, 2021): 1135. http://dx.doi.org/10.3390/en14041135.

Full text

Abstract:

A numerical investigation of the spray-induced turbulence generated from industrial spray nozzles is carried out to better understand the roles of the nozzle spray on the fires or explosions in different accidental scenarios. Numerical simulations are first validated against experimental data in the single nozzle case using the monodisperse and polydisperse assumption for droplet diameters. The polydispersion of the nozzle spray is proven to be necessary to correctly predict the gas and droplet velocities. The turbulent kinetic energy has dominant values inside the spray cone, decreases rapidly with the vertical distance from the spray nozzle, and is strongly affected by the spray droplet diameter. On the contrary, the integral length scale is found to have high values outside the spray cone. Two interacting sprays injected from different nozzles are then investigated numerically using the validated polydisperse model. The water sprays generated from such industrial nozzles can generate turbulence of high intensity in the near-nozzle region, and this intensity decreases with the distance from the nozzles. A better understanding of the turbulence generated by the spray system can be beneficial for the evaluation of several important phenomena such as explosion enhancement. The guideline values obtained from this investigation of single and double nozzles can be useful for large-scale numerical simulations.

APA, Harvard, Vancouver, ISO, and other styles

2

Rudoff, R. C., M. J. Houser, and W. D. Bachalo. "Experiments on Spray Interactions in the Wake of a Bluff Body." Journal of Engineering for Gas Turbines and Power 110, no. 1 (January 1, 1988): 86–93. http://dx.doi.org/10.1115/1.3240091.

Full text

Abstract:

The dynamics of spray drop interaction within the turbulent wake of a bluff body were investigated using the Aerometrics Phase Doppler Particle Analyzer, which determines both drop size and velocity. Detailed measurements obtained included spray drop size, axial and radial velocity, angle of trajectory, and size-velocity correlations. The gas-phase flow field was also ascertained via the behavior of the smallest drops. Results showed dramatic differences in drop behavior when interacting with turbulence for the various size classes. Small drops were recirculated in a pair of toroidal vortices located behind the bluff body, whereas the larger drops followed the general direction of the spray cone angle. This was documented via backlit photography. Local changes in number density were produced as a result of lateral convection and streamwise accelerations and decelerations of various drop size classes. The spray field interaction illustrated by these data effectively reveals the complexity associated with the development of the spray and casts some doubts toward attempting to describe sprays via simple integral quantities such as the Sauter mean diameter.

APA, Harvard, Vancouver, ISO, and other styles

3

Foissac, A., J. Malet, S. Mimouni, P. Ruyer, F. Feuillebois, and O. Simonin. "Eulerian Simulation of Interacting PWR Sprays Including Droplet Collisions." Nuclear Technology 181, no. 1 (January 2013): 133–43. http://dx.doi.org/10.13182/nt13-a15762.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Ghasemi, Abbas, Aaron Pereira, Xianguo Li, and Yi Ren. "Multi-plume sprays interacting with subsonic compressible gas jets." Applied Energy 190 (March 2017): 623–33. http://dx.doi.org/10.1016/j.apenergy.2017.01.008.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Cengiz, Cengizhan, and Salih Ozen Unverdi. "A CFD Study on the Effects of Injection Timing and Spray Inclusion Angle on Performance and Emission Characteristics of a DI Diesel Engine Operating in Diffusion-Controlled and PCCI Modes of Combustion." Energies 16, no. 6 (March 20, 2023): 2861. http://dx.doi.org/10.3390/en16062861.

Full text

Abstract:

In three-dimensional (3D) computational fluid dynamics (CFD) simulations, the effects of injection timing and spray inclusion angle (SIA) on performance and emissions of diffusion-controlled and Premixed Charge Compression Ignition (PCCI) combustion in part load for a heavy-duty direct injection (HDDI) diesel engine are studied. The start of injection (SOI) of a 146° SIA injector is varied between −70 and −10 °crank angle (°CA) after top dead center (ATDC). For −50 °CA ATDC SOI with various SIAs between 80° and 146°, PCCI combustion reduces mono-nitrogen oxide (NOx) emissions significantly compared to conventional diesel combustion (CDC). Due to incomplete combustion in rich zones formed by droplet–cylinder wall interaction, early wide SIA injection deteriorates combustion efficiency (CE) and Indicated Mean Effective Pressure (IMEP) and increases soot and carbon monoxide (CO) emissions. Narrow-angle sprays interacting with the piston bowl elevate CE and IMEP and decrease soot and CO emissions but increases NOx emissions. Optimal combustion is achieved by avoiding fuel droplet–cylinder wall interaction. By spray-targeting at the stepped lip of the piston bowl, 100° SIA and −50 °CA ATDC SOI yield, respectively, the highest CE and IMEP: 97.8% and 3.37 bar and the lowest soot and CO emissions: 33.5 and 2.2 ppm, with acceptable NOx emissions.

APA, Harvard, Vancouver, ISO, and other styles

6

Sinko, K. M., D. Pushka, and B. Chehroudi. "VISUALIZATION OF INTERACTING PILOT AND MAIN DIESEL-TYPE SPRAYS IN AN ENGINE." Journal of Flow Visualization and Image Processing 2, no. 1 (1995): 93–112. http://dx.doi.org/10.1615/jflowvisimageproc.v2.i1.80.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Dunn, Patrick F., and Stephen R. Snarski. "Velocity component and diameter distribution characteristics of droplets within two interacting electrohydrodynamic sprays." Physics of Fluids A: Fluid Dynamics 3, no. 3 (March 1991): 492–94. http://dx.doi.org/10.1063/1.858108.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Patel, Rajesh, Pengfei He, Bo Zhang, and Chao Zhu. "Transport of interacting and evaporating liquid sprays in a gas–solid riser reactor." Chemical Engineering Science 100 (August 2013): 433–44. http://dx.doi.org/10.1016/j.ces.2013.01.005.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Chehroudi, Bruce, K. M. Sinko, W. J. Minkowycz, and S. Shih. "INTERACTING-SPRAYS INJECTION: A NEW CONCEPT FOR NOx AND SMOKE REDUCTION IN DIESEL ENGINES." Atomization and Sprays 8, no. 6 (1998): 673–90. http://dx.doi.org/10.1615/atomizspr.v8.i6.40.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Gao, Jian, Mario F. Trujillo, and Suraj Deshpande. "Numerical Simulation of Hollow-Cone Sprays Interacting with Uniform Crossflow for Gasoline Direct Injection Engines." SAE International Journal of Engines 4, no. 2 (September 11, 2011): 2207–21. http://dx.doi.org/10.4271/2011-24-0007.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

Hahn, Stefan, Norman Nowak, Katharina Schwarz, Janine Schwarz, Martin Tischer, Jessica Meyer, and Wolfgang Koch. "79 Combination of Screening and Higher tier Modelling Approaches for Estimating Inhalation Exposure During Spray Applications." Annals of Work Exposures and Health 67, Supplement_1 (May 1, 2023): i57—i58. http://dx.doi.org/10.1093/annweh/wxac087.139.

Full text

Abstract:

Abstract Sprays are used in workplace as well as in consumer environments. Although spraying has several advantages such as uniform distribution of substances on surfaces in a highly efficient manner it is often prone to high inhalation burden which has to be quantified for adequate risk assessments. There are occupational exposure models with different degree of complexity available that are applied for spray applications. In the presentation we report on an effort to create an overall model for estimating inhalation exposure caused by spray applications by re-analyzing, refining and integrating three already existing models into a 2-level tiered approach. The single models used in this context are a 1- and 2-box mass balance model (Tier 1), Spray Expo and a newly developed binary system model (Tier 2). The Tier 1 level models are used for an initial assessment generally designed to deliver conservative results. Only if product safety cannot be derived from these results higher level models are used which are expected to generate results with a lower degree of conservatism. These higher level models are based on the solution of transport equation in space and time for the ingredients, taking into account the complex evaporation kinetics of interacting binary systems and consider the relevant sources in the spraying and post-spraying phase such as evaporation from droplets and treated surfaces. The presentation will contain the description of the overall model, results on plausibility and sensitivity, and the comparison with measured data.

APA, Harvard, Vancouver, ISO, and other styles

12

Ryan, W., and K. Annamalai. "Group Ignition of a Cloud of Coal Particles." Journal of Heat Transfer 113, no. 3 (August 1, 1991): 677–87. http://dx.doi.org/10.1115/1.2910618.

Full text

Abstract:

Ignition of an isolated single coal particle is known to occur either heterogeneously or homogeneously. While single-particle studies may be useful for dilute coal sprays, their application to burners is limited since ignition occurs in the vicinity of the burners where the spray is dense. Rather than considering an isolated particle, one must consider a collection of particles in order to determine the change in ignition characteristics resulting from particle interactions. Thus, group combustion models have been developed essentially to predict the ignition and combustion characteristics of a larger number of interacting drops/particles. This paper presents results of the ignition characteristics of a spherical cloud of uniformly distributed coal particles in quiescent surroundings using a simple group combustion model. For the conditions studied, the results are as follows: (1) Ignition is heterogeneous if the cloud is dilute and homogeneous if the cloud is dense under the same ambient conditions; (2) there is a minimum ignition time for a given set of initial conditions corresponding to a certain cloud denseness; (3) ignition time is less sensitive to the denseness of the cloud at higher ambient temperatures; and (4) decreased proximate volatile matter can result in either increased or decreased ignition time depending on the cloud denseness (ignition mode). Qualitative comparisons to experimental data are given; however, these comparisons should be approached with caution since the experimental conditions and geometries may be vastly different than those used in the numerical study presented here.

APA, Harvard, Vancouver, ISO, and other styles

13

Mallik, Arnab Kumar, Tushar Pratim Sarma, Aritras Roy, Mahesh V. Panchagnula, and Satyanarayanan Seshadri. "PHASE DOPPLER PARTICLE ANALYSER (PDPA) CHARACTERIZATION AND MODELING OF SPRAYS FROM ORTHOGONALLY INTERACTING WATER AND AIR JETS." Journal of Flow Visualization and Image Processing 27, no. 2 (2020): 199–217. http://dx.doi.org/10.1615/jflowvisimageproc.2020031030.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

Li, Z., M. J. Furlong, T. Yonow, D. J. Kriticos, H. Bao, F. Yin, Q. Lin, X. Feng, and M. P. Zalucki. "Management and population dynamics of diamondback moth (Plutella xylostella): planting regimes, crop hygiene, biological control and timing of interventions." Bulletin of Entomological Research 109, no. 2 (June 22, 2018): 257–65. http://dx.doi.org/10.1017/s0007485318000500.

Full text

Abstract:

AbstractUsing an age-structured process-based simulation model for diamondback moth (DBM), we model the population dynamics of this major Brassica pest using the cropping practices and climate of Guangdong, China. The model simulates two interacting sub-populations (demes), each representing a short season crop. The simulated DBM abundance, and hence pest problems, depend on planting regime, crop hygiene and biological control. A continuous supply of hosts, a low proportion of crop harvested and long residue times between harvest and replanting each exacerbate pest levels. Biological control provided by a larval parasitoid can reduce pest problems, but not eliminate them when climate is suitable for DBM and under certain planting practices. The classic Integrated Pest Management (IPM) method of insecticide application, when pest threshold is reached, proved effective and halved the number of insecticide sprays when compared with the typical practice of weekly insecticide application.

APA, Harvard, Vancouver, ISO, and other styles

15

Fthenakis, V. M., K. W. Schatz, U. S. Rohatgi, and V. Zakkay. "Computation of Flow Fields Induced by Water Spraying of an Unconfined Gaseous Plume." Journal of Fluids Engineering 115, no. 4 (December 1, 1993): 742–50. http://dx.doi.org/10.1115/1.2910207.

Full text

Abstract:

Flow fields induced by the interaction of water sprays and a gaseous plume have been studied in the context of absorbing and dispersing an accidental release of toxic gas in the air. The effectiveness of water sprays in absorbing highly water soluble gases was recently demonstrated in extended laboratory and field tests. In this paper, computer simulations are presented of the Hawk, Nevada Test Site, series of water spray/HF mitigation field tests. The model used, HFSPRAY, is a Eulerean/Lagrangian model which simulates the momentum, mass and energy interactions between a water spray and a turbulent plume of HF in air; the model can predict the flow velocities, temperature, water vapor, and HF concentration fields in two-dimensional large-geometries for spraying in any direction, (i.e., down-flow, inclined-down-flow, up-flow, and co-current horizontal flow). The model was validated against recent data on spraying of water on large releases of HF. It can provide a direct input to the design of water spray systems for HF mitigation.

APA, Harvard, Vancouver, ISO, and other styles

16

Hardalupas, Y., and J. H. Whitelaw. "Interaction Between Sprays From Multiple Coaxial Airblast Atomizers." Journal of Fluids Engineering 118, no. 4 (December 1, 1996): 762–71. http://dx.doi.org/10.1115/1.2835507.

Full text

Abstract:

Phase Doppler measurements of size, velocity, liquid flux, and average mass fractions were obtained in sprays produced by three identical coaxial airblast atomizers, with their axes placed in a triangular arrangement at distances of two air jet diameters from each other; the arrangement simulates the spray interaction in the preburner of the space shuttle main engine with water and air respectively replacing the liquid oxygen and hydrogen of the preburner sprays. Each nozzle comprised a liquid jet with exit diameter of 2.3 mm centred in a 8.95 mm diameter air stream. Two liquid flowrates were examined, while the air flowrate was kept constant, resulting in Weber number at the exit of the nozzle around 1100, air-to-liquid momentum ratio 8.6 and 38, velocity ratio 24 and 51, mass flowrate ratio 0.35 and 0.75, liquid jet Reynolds number 10,000 and 21,000 and air jet Reynolds number around 108,000. The air flow characteristics were compared to the flow without liquid injection. Up to 10 air jet diameters from the nozzle exit, individual spray characteristics dominated and maximum Sauter mean diameters, typically around 150 μm, and liquid flux were observed on the geometrical axes of the nozzles. Spray merging was strong in the region between the nozzle axes, where the Sauter mean diameter reduced and the liquid flux and the mean and rms of the fluctuations of the axial velocity of the droplets and the air flow increased relative to the single spray. Downstream of 25 air jet diameters from the nozzle exit, the multiple sprays merged to a single spray-like flow produced by a nozzle located at the centre of the triangular region between the nozzle axes. Reduction of the liquid flowrate by 50 percent, improved atomization by 25 percent, shortened the axial distance from the nozzles where the individual spray characteristics disappeared by 30 percent and increased the air flow turbulence by 20 percent. Droplet coalescence was negligible for high liquid flowrates, but for reduced liquid flowrates coalescence became important and the Sauter mean diameter increased with the axial distance from the exit by around 15 percent. Spray merging increased the air flow turbulence and the local mass fraction distribution of the air in the region between the nozzle axes by around 50 and 40 percent respectively relative to the single sprays, resulting in a fuel rich region with increased gas flow turbulence which may influence the ignition process in the preburner of the space shuttle main engine.

APA, Harvard, Vancouver, ISO, and other styles

17

Kolanjiyil, Arun V., Ali Alfaifi, Ghali Aladwani, Laleh Golshahi, and Worth Longest. "Importance of Spray–Wall Interaction and Post-Deposition Liquid Motion in the Transport and Delivery of Pharmaceutical Nasal Sprays." Pharmaceutics 14, no. 5 (April 28, 2022): 956. http://dx.doi.org/10.3390/pharmaceutics14050956.

Full text

Abstract:

Nasal sprays, which produce relatively large pharmaceutical droplets and have high momentum, are primarily used to deliver locally acting drugs to the nasal mucosa. Depending on spray pump administration conditions and insertion angles, nasal sprays may interact with the nasal surface in ways that creates complex droplet–wall interactions followed by significant liquid motion after initial wall contact. Additionally, liquid motion can occur after deposition as the spray liquid moves in bulk along the nasal surface. It is difficult or impossible to capture these conditions with commonly used computational fluid dynamics (CFD) models of spray droplet transport that typically employ a deposit-on-touch boundary condition. Hence, an updated CFD framework with a new spray–wall interaction (SWI) model in tandem with a post-deposition liquid motion (PDLM) model was developed and applied to evaluate nasal spray delivery for Flonase and Flonase Sensimist products. For both nasal spray products, CFD revealed significant effects of the spray momentum on surface liquid motion, as well as motion of the surface film due to airflow generated shear stress and gravity. With Flonase, these factors substantially influenced the final resting place of the liquid. For Flonase Sensimist, anterior and posterior liquid movements were approximately balanced over time. As a result, comparisons with concurrent in vitro experimental results were substantially improved for Flonase compared with the traditional deposit-on-touch boundary condition. The new SWI-PDLM model highlights the dynamicenvironment that occurs when a nasal spray interacts with a nasal wall surface and can be used to better understand the delivery of current nasal spray products as well as to develop new nasal drug delivery strategies with improved regional targeting.

APA, Harvard, Vancouver, ISO, and other styles

18

Bukovac, M. J., and D. L. Reichard. "SPRAY DROPLET/CHEMICAL DEPOSIT INTERACTION WITH LEAF SURFACES." HortScience 25, no. 9 (September 1990): 1146a—1146. http://dx.doi.org/10.21273/hortsci.25.9.1146a.

Full text

Abstract:

Most growth regulators and crop protection chemicals are delivered to the plant as aqueous sprays. Spray droplet:plant surface interaction is central to establishing spray and, hence, dose retention by the plant. Further, the nature of chemical deposition from spray droplets plays an important role in determining the efficiency of the active ingredient (a.i.). Using scanning electron microscopy and dispersive x-ray analysis, we investigated chemical deposit formation of selected growth regulators (e.g. ethephon, 2,4, 5-TP, TIBA) on leaf surfaces differing in wettability and surface fine-structure. The a.i. frequently deposited in the form of an annulus on droplet drying, and the degree of spreading was related to surface tension of the spray solution, and wettability, fine-structure and morphology of the leaf surface. Marked differences were observed in spreading following impaction on veins vs. interveinal areas of leaves of Prunus and Pyrus sp. The epidermis over veins was more readily wetted leading to rapid lateral diffusion along veins. Surfactants (e.g. Tween 20, Regulaid) altered the deposition pattern, expanding the annulus and increasing spreading on the leaf surface.

APA, Harvard, Vancouver, ISO, and other styles

19

Han, Z., Z. Xu, and N. Trigui. "Spray/wall interaction models for multidimensional engine simulation." International Journal of Engine Research 1, no. 1 (February 1, 2000): 127–46. http://dx.doi.org/10.1243/1468087001545308.

Full text

Abstract:

Models were developed to describe the spray wall impingement processes that take place in internal combustion engines. In this report focus is placed on the model formulation and experiment assessment of the spray/wall interaction submodels. It is identified that the Leidenfrost phenomenon is very unlikely to occur in a spark ignition (SI) engine including stratified-charge operation in a direct injection spark ignition (DISI) engine. A more comprehensive splashing/deposition threshold function is proposed to include the effects of surface roughness and pre-existing liquid film. Based on the wave phenomena observed on the surface of the liquid crown formed during drop impingement, a new splash breakup model is developed using linear instability analysis. The predicted drop size agrees well with available single-drop impingement experimental data. A new formulation for the post-impingement droplet velocity is also given which uses statistical sampling and jet impingement theory. The proposed models were assessed by comparing computations with two sets of experimental sprays impinging on a flat plate with the use of a pintle nozzle injector for port fuel injection (PFI) engines. The computed spray shape, normal and tangential penetration and droplet size show good agreement with experimental data.

APA, Harvard, Vancouver, ISO, and other styles

20

Fiola, Joseph A., and Donald W. Schaffner. "FOLIAR PREHARVEST CALCIUM TREATMENT INFLUENCE ON YIELD AND QUALITY ATTRIBUTES OF STRAWBERRY." HortScience 27, no. 6 (June 1992): 666d—666. http://dx.doi.org/10.21273/hortsci.27.6.666d.

Full text

Abstract:

The major limiting factors for commercial marketability of strawberries grown in the Northeast is firmness and shelf-life. The major objective of the research is to study basic and applied aspects of exogenous calcium treatments on yield and quality of New Jersey grown berries. In 1990, 8328-1 and 8237-1 (NJUS advanced selections), and `Earliglow' and `Raritan' standards, were treated with 4 foliar Ca sprays (Nutrical) at 10 day intervals from bloom through harvest. In 1991, sprays (3) were applied at bloom, bloom+15 days, and pre-harvest. An `Earliglow' plot was utilized to test timing: bloom, mid-spray, or pre-harvest. Leaf and fruit samples were taken from treated and untreated plots prior to each application. Instron texture tests were performed to quantify firmness; a taste panel evaluated quality (color, texture, flavor, and overall quality). With multiple sprays, there were no significant differences in yield, fruit size, and Brix%, between treatments; however there were significant differences between genotypes and a genotype-by-treatment interaction. The lone bloom spray treatment reduced fruit size. Ethylene was reduced with calcium treatment, respiration was unaffected. Differences in flavor attributes were genotype specific.

APA, Harvard, Vancouver, ISO, and other styles

21

Burger, M., G. Klose, G. Rottenkolber, R. Schmehl, D. Giebert, O. Scha¨fer, R. Koch, and S. Wittig. "A Combined Eulerian and Lagrangian Method for Prediction of Evaporating Sprays." Journal of Engineering for Gas Turbines and Power 124, no. 3 (June 19, 2002): 481–88. http://dx.doi.org/10.1115/1.1473153.

Full text

Abstract:

Polydisperse sprays in complex three-dimensional flow systems are important in many technical applications. Numerical descriptions of sprays are used to achieve a fast and accurate prediction of complex two-phase flows. The Eulerian and Lagrangian methods are two essentially different approaches for the modeling of disperse two-phase flows. Both methods have been implemented into the same computational fluid dynamics package which is based on a three-dimensional body-fitted finite volume method. Considering sprays represented by a small number of droplet starting conditions, the Eulerian method is clearly superior in terms of computational efficiency. However, with respect to complex polydisperse sprays, the Lagrangian technique gives a higher accuracy. In addition, Lagrangian modeling of secondary effects such as spray-wall interaction enhances the physical description of the two-phase flow. Therefore, in the present approach the Eulerian and the Lagrangian methods have been combined in a hybrid method. The Eulerian method is used to determine a preliminary solution of the two-phase flow field. Subsequently, the Lagrangian method is employed to improve the accuracy of the first solution using detailed sets of initial conditions. Consequently, this combined approach improves the overall convergence behavior of the simulation. In the final section, the advantages of each method are discussed when predicting an evaporating spray in an intake manifold of an internal combustion engine.

APA, Harvard, Vancouver, ISO, and other styles

22

Lu, Weixun, Nathaniel K. Newlands, Odile Carisse, David E. Atkinson, and Alex J. Cannon. "Disease Risk Forecasting with Bayesian Learning Networks: Application to Grape Powdery Mildew (Erysiphe necator) in Vineyards." Agronomy 10, no. 5 (April 28, 2020): 622. http://dx.doi.org/10.3390/agronomy10050622.

Full text

Abstract:

Powdery mildew (Erysiphe necator) is a fungal disease causing significant loss of grape yield in commercial vineyards. The rate of development of this disease varies annually and is driven by complex interactions between the pathogen, its host, and environmental conditions. The long term impacts of weather and climate variability on disease development is not well understood, making the development of efficient and durable strategies for disease management challenging, especially under northern conditions. We present a probabilistic, Bayesian learning network model to explore the complex causal interactions between environment, pathogen, and host for three different susceptible northern grape cultivars in Quebec, Canada. This approach combines environmental (weather, climate), pathogen (development stages), and host (crop cultivar-specific susceptibility) factors. The model is evaluated in an operational forecast mode with supervised and algorithm model learning and integrating Global Forecast System (GFS) Ensemble Reforecasts (GEFSR). A model-guided fungicide spray strategy is validated for guiding spray decisions up to 6 days with a 10-day forecast of potential spray efficacy under rain washed off conditions. The model-guided strategy improves fungicide spray decisions; decreasing the number of sprays, and identifying the optimal time to spray to increase spray effectiveness.

APA, Harvard, Vancouver, ISO, and other styles

23

Solomon, A. S. P., J.-S. Shuen, Q.-F. Zhang, and G. M. Faeth. "Measurements and Predictions of the Structure of Evaporating Sprays." Journal of Heat Transfer 107, no. 3 (August 1, 1985): 679–86. http://dx.doi.org/10.1115/1.3247477.

Full text

Abstract:

An experimental and theoretical study of turbulent evaporating sprays is described. Experiments considered round, Freon-11 sprays (Sauter mean diameters of 31 and 58 μm) produced by an air-atomizing injector directed vertically downward in still air. The following structure measurements were made: mean and fluctuating gas velocities, total concentration of Freon-11, drop size and velocity distributions, mean gas temperature, and liquid flux distributions. Three spray models were evaluated using the new measurements: (a) a locally homogeneous flow (LHF) model where interphase transport rates are assumed to be infinitely fast; (b) a deterministic separated flow (DSF) model where finite interphase transport rates are considered but drop-turbulence interactions are ignored; and (c) a stochastic separated flow (SSF) model where effects of finite interphase transport rates and drop-turbulence interactions are considered using random-walk computations for drop motion and transport. The LHF and DSF models performed poorly, since both finite interphase transport rates and drop-turbulence interactions were important for present test conditions. The SSF model gave best agreement between predictions and measurements and appears to be an encouraging approach for treating practical sprays.

APA, Harvard, Vancouver, ISO, and other styles

24

Gonzales, J. W., D. P. Coyne, and W. W. Stroup. "Iron Deficiency Chlorosis and Seed Yield in Dry Edible Beans Grown on High-pH Calcareous Soils." HortScience 33, no. 3 (June 1998): 444f—445. http://dx.doi.org/10.21273/hortsci.33.3.444f.

Full text

Abstract:

Iron deficiency chlorosis (FeDC) can cause significant seed yield reduction in dry beans (Phaseolus vulgaris L.) grown on high-pH calcareous soils. To determine the effects of FeDC on seed yield, and the effect of Fe-spray as a correction factor for FeDC, 22 breeding lines/cultivars were planted on high-pH (8.0), calcareous (3.2–3.5 calcium carbonate equivalent), and low-Fe (1.8–4.2 ppm DTPA) sandy clay loam Tripp soils at Mitchell and Scottsbluff in western Nebraska. A split-plot design was used with Fe treatments as main plots and breeding lines/cultivars as subplots. Three foliar sprays of Fe-EDDHA (2.4 kg·ha–1) were applied at V4, R5, and R7 dry bean growth stages, during 1996 and 1997. Leaf chlorosis was measured simultaneously by using a Minolta Chroma-meter (CIE L* a* b* color space system), a Minolta Chlorophyll-meter (chlorophyll content index), and by visual ratings (1 = normal green to 5 = severe chlorosis). In 1996 no significant Fe-spray × line interaction (P = 0.776) and Fe-spray effect (P = 0.884) on seed yield was observed. Breeding lines showed significant differences in seed yield (P = 0.0001) with WM2-96-5 being the highest-yielding line (4047 kg·ha–1). In 1997 a significant Fe spray × line interaction (P = 0.029) was observed. The cultivar Chase without Fe spray (3375 kg·ha–1), and lines WM2-96-5 (3281 kg·ha–1), WM2-96-8 (3171 kg·ha–1) with Fe spray were the highest yielding entries under those treatments. Differences in visual ratings after the third Fe spray in 1997 were significant (P = 0.004) for Fe spray × line interaction. In 1996 visual ratings were different only for breeding lines. Chlorophyll content index showed a significant Fe spray × line interaction after the second Fe spray (P = 0.022) and after the third Fe spray (P = 0.0003) in 1997.

APA, Harvard, Vancouver, ISO, and other styles

25

Shriram Sathishkumar, Bommisetty Sambasiva Rao, Sidharth Pradeep, Solai Sairam R. M., Balaji Kalaiarasu, and Prabhu Selvaraj. "Modelling and Validating the Spray Characteristics of a Co-axial Twin-Fluid Atomizer Using OpenFOAM." Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 91, no. 1 (January 17, 2022): 35–45. http://dx.doi.org/10.37934/arfmts.91.1.3545.

Full text

Abstract:

Today, the applications of sprays cover a wide range of fields. Their role in internal combustion engines is instrumental in maintaining higher engine efficiency. A deeper understanding of the liquid-gas phase interaction in sprays is crucial to the atomization process. The methods and models used in the simulations have their challenges due to the various discretization schemes and solutions used. To develop and validate the computational models, well defined experimental data is required. In the present work, spray characteristics were studied numerically through OpenFOAM. As the spray characteristics are closely linked with the liquid breakup length, this study focuses on the primary breakup phenomena and the breakup length of the liquid jet emanating from the twin-fluid co-axial flow atomizer. Numerical simulations were performed for a wide range of initial conditions and the breakup length of the spray was validated against the experimental observed by Sivadas et al., [26]. These simulations were carried out using a Eulerian based VOF solver that models the fluid as a continuum. K-Epsilon model was used to predict the turbulent nature of the spray. The air and water velocities were varied between 19.0 to 31.3 m/s and 0.7 to 1.8 m/s respectively. The proposed model was able to predict the computed breakup length within 20% of the experimental values. The present model can be further extended to test for a co-axial swirl injector to predict finer spray formation.

APA, Harvard, Vancouver, ISO, and other styles

26

Asgari, Behrad, and Ehsan Amani. "An improved spray-wall interaction model for Eulerian-Lagrangian simulation of liquid sprays." International Journal of Multiphase Flow 134 (January 2021): 103487. http://dx.doi.org/10.1016/j.ijmultiphaseflow.2020.103487.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Womac, Alvin R., Erdal Ozkan, Heping Zhu, John Kochendorfer, and Hongyoung Jeon. "Status of Spray Penetration and Deposition in Dense Field Crop Canopies." Journal of the ASABE 65, no. 5 (2022): 1107–17. http://dx.doi.org/10.13031/ja.15091.

Full text

Abstract:

HighlightsCrop production practices, spray drift control, and sprayer productivity affect spray penetration into dense crop canopies.Question is raised whether airflows near foliar surfaces or within the canopy can assist spray penetration under windy conditions.Current structural descriptions of canopies do not accommodate droplet trajectories to improve spray application.New nozzle tip designs, sensors, and air-assisted spraying need tuning to improve spray penetration and deposition.Abstract. The objective of this study was to review representative publications for improved knowledge of spraying dense field crop canopies to augment the current understanding of the interaction between target foliage characteristics, spray practices, and the environment. Emphasis was placed on measured deep-canopy spray deposits made by full-scale sprayers and studies of airflow within and around crop canopies. Airflow could act as a spray droplet carrier and/or indicator of the internal canopy structure that restricts droplet penetration. High variation in natural airflows was noted in several studies. Crop canopy descriptions for spray studies were generally limited to overall canopy/row dimensions, descriptions of individual plant structures, leaf shapes, and leaf area index. Few studies evaluated the internal canopy “openness” with characteristic shape and size of internal volumes that would accommodate spray droplet trajectories. There have been significant increases in available spray tip designs with multiple orifices, discharge configurations, and droplet sizes that offered the applicator many choices. Advanced sprayer technologies ranging from nozzle control to sensor navigation are available, provided that suitable algorithms can be developed in a timely manner that pertain to a wide variety of spray and crop conditions. The air-assist technique provides a dynamic alternative to traditional over-the-top sprays for increasing spray penetration and deposit, advocating that the specifics of air discharge, spray droplet sizes, and canopy structure can be integrated. The complexity of the spraying process needs an extensive collaborative effort of many stakeholders to develop solutions for sprays to penetrate foliage that is subject to diseases and pests. Keywords: Air-assisted sprayer, Airflow, Boom sprayer, Canopy openness, Droplet trajectory, Foliar canopy, Foliar density, Row crops, Spray blockage, Spray coverage, Spray deposit, Spray nozzles.

APA, Harvard, Vancouver, ISO, and other styles

28

GÓRKA, Krzysztof, Bartosz KAŹMIERSKI, and Łukasz KAPUSTA. "Numerical analysis of the flow rig for UWS spray examination in exhaust system-relevant conditions." Combustion Engines 186, no. 3 (September 13, 2021): 103–12. http://dx.doi.org/10.19206/ce-141182.

Full text

Abstract:

In the present study, a flow rig with optical access intended for spray investigations in exhaust system-relevant conditions was analysed in terms of flow and temperature in the spray area using numerical simulations. The operation of the rig was examined for a wide range of exhaust mass flow rates, temperatures and various forms of UWS (urea-water solution) spray plumes. The locations of the injector and thermocouple were verified. Both conventional and flash-boiling injections were considered to assess the effect of the interaction of sprays with a gas flow. The results showed a highly uniform flow in the visualisation area, with only minor fluctuations near the walls. A similar observation was carried out for the temperature distribution. It was found that the extreme operating conditions caused substantial deformations of the spray plumes. However, the selected injector location allowed us to properly observe the spray formation regardless of the flow conditions. The study showed that the examined test rig enabled reliable spray investigations for a wide range of operating points.

APA, Harvard, Vancouver, ISO, and other styles

29

Horgan, D. B., and R. E. Gaskin. "The effect of copper on the uptake and translocation of spirotetramat insecticide on kiwifruit." New Zealand Plant Protection 68 (January 8, 2015): 26–31. http://dx.doi.org/10.30843/nzpp.2015.68.5794.

Full text

Abstract:

Spirotetramat (Movento) is a systemic insecticide that is used to control scale insects on kiwifruit The use of protectant copper sprays on kiwifruit has become increasingly common due to the bacterial disease Pseudomonas syringae pv actinidiae This study investigated the interaction of copper with spirotetramat and how it influenced the uptake and translocation of spirotetramat within the plant Movento 100SC sprays should not be tank with copper sprays because the uptake and translocation of spirotetramat is likely to be compromised These negative effects were minimised when an organosilicone/organic fluid blend adjuvant (DuWett) was included in the tank mix Preand post spray applications of copper at least 1 week either side of spirotetramat applications are unlikely to significantly affect the uptake and translocation of spirotetramat and thus have any effect on its activity There were no marked differences between two commercial copper formulations in their effects on spirotetramat uptake but minor differences in translocation were observed

APA, Harvard, Vancouver, ISO, and other styles

30

Slayzak, S. J., R. Viskanta, and F. P. Incropera. "Effects of Interactions Between Adjoining Rows of Circular, Free-Surface Jets on Local Heat Transfer From the Impingement Surface." Journal of Heat Transfer 116, no. 1 (February 1, 1994): 88–95. http://dx.doi.org/10.1115/1.2910888.

Full text

Abstract:

Experiments have been conducted to obtain single-phase local heat transfer coefficient distributions associated with impingement of one or two rows of circular, free-surface water jets on a constant heat flux surface. The nozzle diameter, the centerline-to-centerline distance between nozzles in a row, and the nozzle-to-heater separation distance were fixed at 4.9, 6.3, and 89.7 mm, respectively. Two row-to-row separations (81 and 51 mm) were considered, and nozzle discharge Reynolds numbers were varied over the range from 16,800 to 30,400. The interaction zone created by opposing wall jets from adjacent rows is characterized by an upwelling of spent flow (an interaction fountain) for which local coefficients can approach those of the impingement zones. Interactions between wall jets associated with nozzles in one row can create sprays that impact the adjoining row with sufficient momentum to induce a dominant/subordinate row behavior. In this case the interaction zone is juxtaposed with the subordinate row, and local coefficients in the impingement and wall jet regions of the affected row may be significantly enhanced. This result contrasts with the deleterious effects of crossflow reported for submerged jets throughout the literature. Spray-induced enhancements, as well as interaction zone maxima, increase with decreasing row-to-row pitch and with increasing Reynolds number.

APA, Harvard, Vancouver, ISO, and other styles

31

Huang*, Jinsheng, and Sieglinde Snapp. "Interactive Effects of K and B on Tomato Shoulder Check, a Quality Defect in Fresh Market Tomato." HortScience 39, no. 4 (July 2004): 803E—804. http://dx.doi.org/10.21273/hortsci.39.4.803e.

Full text

Abstract:

Potassium (K) and boron (B) nutrition play an important role in control of tomato quality. To evaluate the interactive effects of K and B on yield and fruit quality in fresh market tomatoes, two-year field experiments were conducted in 2002 and 2003 in Southwest Michigan, using the industry standard cultivar `Mountain Spring' and recommended practices for irrigated, staked fresh market production. Six treatments evaluated three fertilizer regimes applied during fruit development (1N:1K, 1N:2K and 1N:3K) and two weekly B foliar sprays (none and 300 mg·L-1 B) at fruit set stage. Increasing K concentration in the fertilizer increased K content in both leaf and fruit tissue, but reduced calcium content in leaf tissue. 1N:3K fertilizer treatment increased tomato shoulder check incidence. The overall total percent shoulder check defect was 32.7%, 33.5% and 38.2% for 1N:1K, 1N:2K and 1N:3K fertilizers, respectively. Weekly B foliar spray increased both tomato marketable yield and fruit quality. Less shoulder check incidence was obtained with a foliar B spray. Boron foliar spray also increased K content in fruit tissue for 1N:1K and 1N:2K treatments. The 1N:2K plus B foliar spray is recommended for improving tomato yield and quality.

APA, Harvard, Vancouver, ISO, and other styles

32

Desantes, Jose M., Jose M. Garcia-Oliver, Ricardo Novella, and Leonardo Pachano. "A numerical study of the effect of nozzle diameter on diesel combustion ignition and flame stabilization." International Journal of Engine Research 21, no. 1 (July 19, 2019): 101–21. http://dx.doi.org/10.1177/1468087419864203.

Full text

Abstract:

The role of nozzle diameter on diesel combustion is studied by performing computational fluid dynamics calculations of Spray A and Spray D from the Engine Combustion Network. These are well-characterized single-hole sprays in a quiescent environment chamber with thermodynamic conditions representative of modern diesel engines. First, the inert spray evolution is described with the inclusion of the concept of mixing trajectories and local residence time into the analysis. Such concepts enable the quantification of the mixing rate, showing that it decreases with the increase in nozzle diameter. In a second step, the reacting spray evolution is studied focusing on the local heat release rate distribution during the auto-ignition sequence and the quasi-steady state. The capability of a well-mixed-based and a flamelet-based combustion model to predict diesel combustion is also assessed. On one hand, results show that turbulence–chemistry interaction has a profound effect on the description of the reacting spray evolution. On the other hand, the mixing rate, characterized in terms of the local residence time, drives the main changes introduced by the increase of the nozzle diameter when comparing Spray A and Spray D.

APA, Harvard, Vancouver, ISO, and other styles

33

Carreño Ruiz, Manuel, Nicoletta Bloise, Giorgio Guglieri, and Domenic D’Ambrosio. "Numerical Analysis and Wind Tunnel Validation of Droplet Distribution in the Wake of an Unmanned Aerial Spraying System in Forward Flight." Drones 6, no. 11 (October 29, 2022): 329. http://dx.doi.org/10.3390/drones6110329.

Full text

Abstract:

Recent developments in agriculture mechanization have generated significant challenges towards sustainable approaches to reduce the environmental footprint and improve food quality. This paper highlights the benefits of using unmanned aerial systems (UASs) for precision spraying applications of pesticides, reducing the environmental risk and waste caused by spray drift. Several unmanned aerial spraying system (UASS) operation parameters and spray system designs are examined to define adequate configurations for specific treatments. A hexarotor DJI Matrice 600 equipped with T-Motor “15 × 5” carbon fiber blades is tested numerically using computational fluid dynamics (CFD) and experimentally in a wind tunnel. These tests assess the aerodynamic interaction between the wake of an advancing multicopter and the fine droplets generated by atomizers traditionally used in agricultural applications. The aim of this research is twofold. First, we analyze the effects of parameters such as flight speed (0, 2, and 3 m·s−1), nozzle type (hollowcone and fan), and injection pressure (2–3 bar) on spray distribution. In the second phase, we use data from the experimental campaign to validate numerical tools for the simulation of rotor–droplet interactions necessary to predict spray’s ground footprint and to plan a precise guidance algorithm to achieve on-target deposition and reduce the well-known droplet drift problem.

APA, Harvard, Vancouver, ISO, and other styles

34

Poudel, Anuj, Satish Kumar Singh, Raimundo Jiménez-Ballesta, Surendra Singh Jatav, Abhik Patra, and Astha Pandey. "Effect of Nano-Phosphorus Formulation on Growth, Yield and Nutritional Quality of Wheat under Semi-Arid Climate." Agronomy 13, no. 3 (March 7, 2023): 768. http://dx.doi.org/10.3390/agronomy13030768.

Full text

Abstract:

Appropriate phosphorus (P) management techniques increase yield and nutritional properties while minimizing environmental concerns. The widespread use of nano-fertilizers (NFs) in agriculture endangers soil and plants. It is vital to research the behavior of nano-phosphors (nano-P) on plant growth and quality, as well as their technique of interaction with soil properties in order to obtain key ecosystem benefits. With this in mind, a field experiment was conducted using wheat as a test crop to explore the impact of nano phosphorus (nano-P) on soil. The study’s goal was to examine how the foliar application of nano-P to wheat affects its growth, yield and nutrient concentration. Treatments consisted of: T1: 100% NPK (120:137:72 kg N:P2O5:K2O ha−1) by RDF (recommended dose of fertilizer); T2: 100% NPK by RDF + 2 foliar sprays of nano-P @ 494.21 mL ha−1; T3: 100% NK + 0% P (no foliar); T4: 100% NK + 75% P + 2 foliar sprays of nano-P @ 494.21 mL ha−1; T5: 100% NK + 50% P + 2 foliar sprays of nano-P @ 494.21 mL ha−1;T6: 100% NK + 0% P + 2 foliar sprays of nano-P @ 494.21 mL ha−1; T7: 100% NPK by RDF + 1 foliar spray of nano-P @ 494.21 mL ha−1; T8: 100% NK + 75% P + 1 foliar spray of nano-P @ 494.21 mL ha−1; T9: 100% NPK + 1 foliar spray of nano-P @ 494.21 mL ha−1; T10-100% NK + 75% P + 1 foliar spray of nano-P @ 494.21 mL ha−1. According to the findings, applying 100% NK + 75% P + 2 foliar applications of nano-P at the tillering and panicle initiation stages increased yield over 100% RDF by 37.1%. Additionally, the highest micronutrient concentration (Zn (36.4 mg kg−1), Cu (21.2 mg kg−1), Mn (22.9 mg kg−1) and Fe (61.1 mg kg−1)) in grain were noticed in T3 (100% NK + 0% P no foliar spray of nano-P) treatment, which was superior to T1 (100% NPK). Furthermore, foliar application of nano-P fertilizer in combination with different levels of diammonium phosphate (DAP) slightly increased the amount of N, P and K, as well as micronutrients in post-harvest soil. In summary, the use of 100% NK + 75% + 2 foliar applications of nano-P saved 25% recommendation dose P if supplied as nano-P as a form of phosphorus, and can be a suitable substitute for DAP, especially in smart agriculture, as it possibly reduces P leaching into groundwater, while maintaining or increasing wheat crop yield over the 100% RDF.

APA, Harvard, Vancouver, ISO, and other styles

35

K, SUBBIAH, and RANIPERUMAL . "STUDIES ON THE EFFECT OF N, K AND CaCl2 ON FRUIT CRACKING, SKIN THICKNESS AND DENSITY OF TOMATO." Madras Agricultural Journal 81, March (1994): 138–40. http://dx.doi.org/10.29321/maj.10.a01323.

Full text

Abstract:

Field experiment conducted during kharif season to study the effect of N (0, 40, 80, 120 & 160 kg/ha) K (0.50 and 100 kg K20/ha and CaCl2 sprays (0.0% & 0.5%) on fruit cracking, skin thickness and density of fruits of tomatoes (Co.I and Co,3) grown in yertisol indicated that 0.5 per cent CaCl2 sprays significantly decreased the fruit cracking. The interaction due to the levels of N, K and CaCl2 sprays had marked effect on the skin thickness. The interactions of N x K and Nx Var had significant influence on the density of fruits.

APA, Harvard, Vancouver, ISO, and other styles

36

Yule, A. J., and D. G. Salters. "On the Distance Required to Atomize Diesel Sprays Injected from Orifice-Type Nozzles." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 209, no. 3 (July 1995): 217–26. http://dx.doi.org/10.1243/pime_proc_1995_209_205_02.

Full text

Abstract:

Conductivity probe measurements, using ranges of nozzles, liquid properties and gas densities, have revealed more extensive and reliable information on the break-up process of diesel sprays than has been published to date. The spray generated from a single-hole orifice-type nozzle has an incompletely atomized break-up length which typically extends at least 100 hole diameters downstream. The physical structure of this break-up zone varies, depending on the liquid properties and both initial and boundary conditions, from that of a central liquid column, with outer drops and ligaments, to, more typically, that of a chaotic ‘wire wool’ structure of ligaments and drops. Time variations of the break-up length are found during spray pulses and concentrations of poorly atomized liquid are convected downstream in the form of coherent structures. The existence of this zone has repercussions with respect to spray-gas flow interaction, fuel vaporization and wall wetting in internal combustion engines.

APA, Harvard, Vancouver, ISO, and other styles

37

Vachharajani, NN, W.-C. Shyu, PS Nichola, and DW Boulton. "A Pharmacokinetic Interaction Study Between Butorphanol and Sumatriptan Nasal Sprays in Healthy Subjects: Importance of the Timing of Butorphanol Administration." Cephalalgia 22, no. 4 (May 2002): 282–87. http://dx.doi.org/10.1046/j.1468-2982.2002.00359.x.

Full text

Abstract:

Sumatriptan and butorphanol nasal sprays are commonly used agents for the management of migraine headaches. Under certain circumstances, these two agents may be administered closely in time. However, the possibility of a pharmacokinetic interaction and the safety of this regime have not been examined. In this crossover design study, 24 healthy subjects received the following four treatments, each separated by at least 7 days: 1 mg butorphanol (Stadol NS7®); 20 mg sumatriptan (Imitrex® Nasal Spray); or both formulations together with butorphanol administered either 1 or 30 min after sumatriptan. Serial plasma samples were collected for 24 h post-dose and analysed for butorphanol and/or sumatriptan by HPLC-MS/MS. Butorphanol plasma concentrations were reduced when it was administered 1 min (mean 28.6% decrease in AUC0-∞) , but not 30 min, after sumatriptan. The pharmacokinetics of sumatriptan were not substantially altered by butorphanol. The combination of nasally administered sumatriptan and butorphanol appeared safe. However, if butorphanol nasal spray is administered < 30 min after sumatriptan nasal spray, the analgesic effect of butorphanol may be diminished due to reduced nasal absorption resulting from probable transient vasoconstriction of nasal blood vessels by sumatriptan.

APA, Harvard, Vancouver, ISO, and other styles

38

Pandal, Adrian, Jose M. Garcia-Oliver, and Jose M. Pastor. "Eulerian CFD modeling of nozzle geometry effects on ECN Sprays A and D: assessment and analysis." International Journal of Engine Research 21, no. 1 (October 24, 2019): 73–88. http://dx.doi.org/10.1177/1468087419882500.

Full text

Abstract:

Diesel spray modeling is a multi-scale problem with complex interactions between different flow regions, that is, internal nozzle flow, near-nozzle region and developed spray, including evaporation and combustion. There are several modeling approaches that have proven particularly useful for some spray regions although they have struggled at other areas, while Eulerian modeling has shown promise in dealing with all characteristics at a reasonable computational effort for engineering calculations. In this work, the [Formula: see text]–Y single-fluid diffuse-interface model, based on scale separation assumptions at high Reynolds and Weber numbers, is used to simulate the engine combustion network Sprays A and D within a Reynolds-averaged Navier–Stokes turbulence modeling approach. The study is divided into two parts. First of all, the larger diameter Spray D is modeled from the nozzle flow till evaporative spray conditions, obtaining successful prediction of numerous spray metrics, paying special attention to the near-nozzle region where spray dispersion and interfacial surface area can be validated against measurements conducted at the Advanced Photon Source at Argonne National Laboratory, including both the ultra-small-angle X-ray scattering and the X-ray radiography. Afterwards, an analysis of the modeling predictions is made in comparison with previous results obtained for Spray A, considering the nozzle geometry effects in the modeling behavior.

APA, Harvard, Vancouver, ISO, and other styles

39

Stanton, Donald W., and Christopher J. Rutland. "Multi-dimensional modeling of thin liquid films and spray-wall interactions resulting from impinging sprays." International Journal of Heat and Mass Transfer 41, no. 20 (October 1998): 3037–54. http://dx.doi.org/10.1016/s0017-9310(98)00054-4.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Hill, M. G. "Does Psa affect kiwifruit susceptibility to leafrollers." New Zealand Plant Protection 66 (January 8, 2013): 162–69. http://dx.doi.org/10.30843/nzpp.2013.66.5587.

Full text

Abstract:

Analysis of kiwifruit industry pest monitoring and spray diary data showed increases in the incidence of leafroller larvae on fruit during crop monitoring in the 2011/12 season in regions with the virulent strain of the disease Pseudomonas syringae pv actinidiae (PsaV) Four factors were considered as explanations PsaV infection and its effects on plant defences leafroller sprays PsaV sprays and leafroller sampling The most plausible cause of the increased leafroller incidence is PsaV infection A putative mechanism is hormonal crosstalk resulting in a tradeoff between pest and pathogen resistance The susceptibility of vines to leafrollers in PsaVinfected regions appears to persist for several weeks longer after fruit set than in uninfected vines The paper discusses the need to develop a better understanding of the interactions of biotic and abiotic stressors on plant defence responses to pests and diseases and to incorporate these into a plantdefencecentred approach to Integrated Pest Management

APA, Harvard, Vancouver, ISO, and other styles

41

Lackmann, Tim, Andreas Nygren, Anders Karlsson, and Michael Oevermann. "Investigation of turbulence–chemistry interactions in a heavy-duty diesel engine with a representative interactive linear eddy model." International Journal of Engine Research 21, no. 8 (December 5, 2018): 1469–79. http://dx.doi.org/10.1177/1468087418812319.

Full text

Abstract:

Simulations of a heavy-duty diesel engine operated at high-load and low-load conditions were compared to each other, and experimental data in order to evaluate the influence of turbulence–chemistry interactions on heat release, pressure development, flame structure, and temperature development are quantified. A recently developed new combustion model for turbulent diffusion flames called representative interactive linear eddy model which features turbulence–chemistry interaction was compared to a well-stirred reactor model which neglects the influence of turbulent fluctuations on the mean reaction rate. All other aspects regarding the spray combustion simulation like spray break-up, chemical mechanism, and boundary conditions within the combustion chamber were kept the same in both simulations. In this article, representative interactive linear eddy model is extended with a progress variable, which enables the model to account for a flame lift-off and split injection, when it is used for diffusion combustion. In addition, the extended version of representative interactive linear eddy model offers the potential to treat partially premixed and premixed combustion as well. The well-stirred reactor model was tuned to match the experimental results, thus computed pressure and apparent heat release are in close agreement with the experimental data. Representative interactive linear eddy model was not tuned specifically for the case and thus the computed results for pressure and heat release are in reasonable agreement with experimental data. The computational results show that the interaction of the turbulent flow field and the chemistry reduce the peak temperatures and broaden up the turbulent flame structure. Since this is the first study of a real combustion engine (metal engine) with the newly developed model, representative interactive linear eddy model appears as a promising candidate for predictions of spray combustion in engines, especially in combustion regimes where turbulence–chemistry interaction plays an even more important role like, example given, in low-temperature combustion or combustion with local extinction and re-ignition.

APA, Harvard, Vancouver, ISO, and other styles

42

R. Birari, Tushar, Shubhangi Patil, H. C. Badgujar, and S. S. Patil. "Influence of Urea Sprays on Growth and Yield of Herbage Amaranthus (Amaranthus spp)." International Journal of Current Microbiology and Applied Sciences 11, no. 12 (December 10, 2022): 191–94. http://dx.doi.org/10.20546/ijcmas.2022.1112.019.

Full text

Abstract:

The field experiment was conducted to evaluated varietal response of urea foliar sprays on growth and yield of leafy amaranthus, there were two varieties (Cv.Suvarna and Cv.Phule Kartiki) with three concentration of urea sprayings along with water spray and control. Thus in all ten treatment combinations were replicated thrice in FRBD in winter season at Oilseeds Research Station, Jalgaon of Maharashtra State. Among the varieties studied, maximum yield of 148.93 q/ha was recorded by Cv.Suvarna than the Cv.Phule Kartiki (124.35q). Among the urea spraying treatments, the treatment of spraying 0.75 % urea was found more beneficial than the rest of spray treatments studied and the control it recorded yield of 152.66 q/ha. Among the interactions, the superior treatment combination was Cv.Suvarna + 0.75 % urea spraying and it resulted highest yield of 166.44q/ha of leaf amaranthus.

APA, Harvard, Vancouver, ISO, and other styles

43

Jafarmadar, Samad, Shram Khalilarya, Sina Shafee, and Ramin Barzegar. "Modeling the effect of spray/wall impingement on combustion process and emission of DI diesel engine." Thermal Science 13, no. 3 (2009): 23–33. http://dx.doi.org/10.2298/tsci0903023j.

Full text

Abstract:

This work is presented to study the effect of spray impinging on the combustion process and emissions in a direct injection diesel engine at various engine speeds. Computations are carried out using a three-dimensional modeling for sprays, spray-wall interactions, flow field, emission, and combustion process. Results indicate an increase in engine speed leads to increased spray impinging (wall film formation), turbulence intensity and average wall temperature in cylinder. The enhanced air/fuel mixing and intensified evaporation of wall film decreases soot emission by reducing the extent of the fuel rich regions specially in impinging zones. Also at higher engine speeds, combustion is delayed and fuel is consumed in a shorter time period by the enhanced air and fuel mixing. The shorter combustion duration provides less available time for soot and NOx formations. However, only a few attempts have been made to address the effect of impingement of spray with piston walls on the emissions and combustion process. The results of model in addition to approving the corresponding data in the literature are also compared with the experimental data and shown good agreement.

APA, Harvard, Vancouver, ISO, and other styles

44

Sirignano, William A. "Fluid Dynamics of Sprays—1992 Freeman Scholar Lecture." Journal of Fluids Engineering 115, no. 3 (September 1, 1993): 345–78. http://dx.doi.org/10.1115/1.2910148.

Full text

Abstract:

Various theoretical and computational aspects of the fluid dynamics of sprays are reviewed. Emphasis is given to rapidy vaporizing sprays on account of the richness of the scientific phenomena and the several, often disparate, time scales. Attention is given to the behavior of individual droplets including the effects of forced convection due to relative droplet-gas motion, Stefan convection due to the vaporization or condensation of the liquid, internal circulation of the liquid, interactions with neighboring droplets, and interactions with vortical eddies. Flow field details in the gas boundary layer and wake and in the liquid droplet interior are examined. Also, the determinations of droplet lift and drag coefficients and Nusselt and Sherwood numbers and their relationships with Reynolds number, transfer number, Prandtl and Schmidt numbers, and spacing between neighboring droplets are extensively discussed. The spray equations are examined from several aspects; in particular, two-continua, multi-continua, discrete-particle, and probabilistic formulations are given. The choice of Eulerian or Lagrangian representation of the liquid-phase equations within these formulations is discussed including important computational issues and the relationship between the Lagrangian method and the method of characteristcis. Topics for future research are suggested.

APA, Harvard, Vancouver, ISO, and other styles

45

McDonell, V. G., and G. S. Samuelsen. "An Experimental Data Base for the Computational Fluid Dynamics of Reacting and Nonreacting Methanol Sprays." Journal of Fluids Engineering 117, no. 1 (March 1, 1995): 145–53. http://dx.doi.org/10.1115/1.2816804.

Full text

Abstract:

The present data set consists of detailed measurements obtained within methanol sprays produced by a research atomizer which is operated with three atomizing air modes: none, non-swirling, and swirling. In addition, the cases with nonswirling and swirling atomizing air are characterized under reacting conditions. In each case, state-of-the-art diagnostics are applied. Measurements of the gas phase velocities in both the single and two-phase cases, droplet size distributions, and vapor concentration are obtained. The data are reported in a standardized format to ensure usefulness as modeling challenges. The results obtained reveal the presence of significant interaction between phases and significant changes in spray structure as a result of altering the atomizing air characteristics. Efforts have been directed toward delineation of errors and comparison with existing data sets where possible. The results is a comprehensive data base for vaporizing sprays under reacting and non-reacting conditions which permit a systematic variation in aerodynamic effects to be explored.

APA, Harvard, Vancouver, ISO, and other styles

46

Naz, M. Y., S. A. Sulaiman, B. Ariwahjoedi, and Ku Zilati Ku Shaari. "Investigation of Vortex Clouds and Droplet Sizes in Heated Water Spray Patterns Generated by Axisymmetric Full Cone Nozzles." Scientific World Journal 2013 (2013): 1–9. http://dx.doi.org/10.1155/2013/796081.

Full text

Abstract:

The hot water sprays are an important part of many industrial processes, where the detailed knowledge of physical phenomena involved in jet transportation, interaction, secondary breakup, evaporation, and coalescence of droplets is important to reach more efficient processes. The objective of the work was to study the water spray jet breakup dynamics, vortex cloud formation, and droplet size distribution under varying temperature and load pressure. Using a high speed camera, the spray patterns generated by axisymmetric full cone nozzles were visualized as a function water temperature and load pressure. The image analysis confirmed that the spray cone angle and width do not vary significantly with increasing Reynolds and Weber numbers at early injection phases leading to increased macroscopic spray propagation. The formation and decay of semitorus like vortex clouds were also noticed in spray structures generated at near water boiling point temperature. For the nozzle with smallest orifice diameter (1.19 mm), these vortex clouds were very clear at 90°C heating temperature and 1 bar water load pressure. In addition, the sauter mean diameter (SMD) of the spray droplets was also measured by using Phase Doppler Anemometry (PDA) at different locations downstream of the nozzle exit. It was noticed that SMD varies slightly w.r.t. position when measured at room temperature whereas at higher temperature values, it became almost constant at distance of 55 mm downstream of the nozzle exit.

APA, Harvard, Vancouver, ISO, and other styles

47

Nealis, Vincent, and Kees van Frankenhuyzen. "INTERACTIONS BETWEEN BACILLUS THURINGIENSIS BERLINER AND APANTELES FUMIFERANAE VIER. (HYMENOPTERA: BRACONIDAE), A PARASITOID OF THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (CLEM.) (LEPIDOPTERA: TORTRICIDAE)." Canadian Entomologist 122, no. 4 (August 1990): 585–94. http://dx.doi.org/10.4039/ent122585-7.

Full text

Abstract:

AbstractInteractions between Bacillus thuringiensis Berliner and Apanteles fumiferanae Viereck as mortality factors of the spruce budworm, Choristoneura fumiferana (Clemens), were investigated by placing parasitized and nonparasitized budworm larvae on foliage with and without spray deposits of a commercial formulation of B. thuringiensis. The effect of larval age (and, thus, the timing of spray applications) was examined by using peak third-instar and peak fourth-instar larvae. We demonstrated that parasitized larvae are more likely to survive exposure to B. thuringiensis because they feed less than non-parasitized larvae and are thus less likely to acquire a lethal dose of the bacterium. Bacillus thuringiensis nevertheless reduced parasitoid populations by 50–60% by killing their hosts before parasitoid emergence. This negative impact of B. thuringiensis on parasitoid survival was decreased when exposure of budworm larvae to spray deposits was delayed from peak third to peak fourth instar. The enhanced survival of parasitoids offset the lower mortality as a result of B. thuringiensis in the delayed sprays. We conclude that B. thuringiensis applied when budworm larval populations are at peak fourth instar or later would complement rather than interfere with the beneficial effects of A. fumiferanae. The implications for budworm management strategies are discussed.

APA, Harvard, Vancouver, ISO, and other styles

48

Lucchini, Tommaso, Gianluca D’Errico, and Daniele Ettorre. "Numerical investigation of the spray–mesh–turbulence interactions for high-pressure, evaporating sprays at engine conditions." International Journal of Heat and Fluid Flow 32, no. 1 (February 2011): 285–97. http://dx.doi.org/10.1016/j.ijheatfluidflow.2010.07.006.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Desantes, Jose M., José M. García-Oliver, Antonio García, and Tiemin Xuan. "Optical study on characteristics of non-reacting and reacting diesel spray with different strategies of split injection." International Journal of Engine Research 20, no. 6 (May 13, 2018): 606–23. http://dx.doi.org/10.1177/1468087418773012.

Full text

Abstract:

Even though studies on split-injection strategies have been published in recent years, there are still many remaining questions about how the first injection affects the mixing and combustion processes of the second one by changing the dwell time between both injection events or by the first injection quantity. In this article, split-injection diesel sprays with different injection strategies are investigated. Visualization of n-dodecane sprays was carried out under both non-reacting and reacting operating conditions in an optically accessible two-stroke engine equipped with a single-hole diesel injector. High-speed Schlieren imaging was applied to visualize the spray geometry development, while diffused background-illumination extinction imaging was applied to quantify the instantaneous soot production (net result of soot formation and oxidation). For non-reacting conditions, it was found that the vapor phase of second injection penetrates faster with a shorter dwell time and independently of the duration of the first injection. This could be explained in terms of one-dimensional spray model results, which provided information on the local mixing and momentum state within the flow. Under reacting conditions, interaction between the second injection and combustion recession of the first injection is observed, resulting in shorter ignition delay and lift-off compared to the first injection. However, soot production behaves differently with different injection strategies. The maximum instantaneous soot mass produced by the second injection increases with a shorter dwell time and with longer first injection duration.

APA, Harvard, Vancouver, ISO, and other styles

50

Al-Zubade, Ammar, Timothy Phillips, Mark A. Williams, Krista Jacobsen, and David Van Sanford. "Effect of Biofertilizer in Organic and Conventional Systems on Growth, Yield and Baking Quality of Hard Red Winter Wheat." Sustainability 13, no. 24 (December 15, 2021): 13861. http://dx.doi.org/10.3390/su132413861.

Full text

Abstract:

A two-year study (harvest years 2019 and 2020) was conducted to investigate the effect of a commercially available biofertilizer, in combination with variable nitrogen (N) rate, on bread baking quality and agronomic traits in hard winter wheat grown in conventional (CONV) and organic (ORG) farming systems in Kentucky, USA. The hard red winter wheat cultivar ‘Vision 45’ was used with three N rates (44, 89.6 and 134.5 kg/ha as Low, Med and High, respectively) and three biofertilizer spray regimes (no spray, one spray and two sprays). All traits measured were significantly affected by the agricultural production system (CONV or ORG) and N rate, although trends in their interactions were inconsistent between years. In Y2, yield was greatest in treatments with high N rates and in the ORG system. Biofertilizer treatments had a negative to neutral effect on grain yield. Baking quality traits such as protein content, lactic acid solvent retention capacity and sedimentation value (SV) were consistently greater in the CONV system and increased with the higher N application rates. Similarly, biofertilizer application had no effect on predictive baking quality traits, except for SV in year 1 of the study, where it increased with two sprays. Loaf volume was consistently greater from wheat grown in CONV treatments. From these results, we conclude that further research is warranted to evaluate the potential for biofertilizers to enhance N uptake and affect bread baking quality or other end-use traits. Additional research may be especially useful in organic production systems where biologically based N fertilizers are utilized, and treatments were not negatively affected by biofertilizer applications. Such strategies may be needed to increase protein quantity and gluten quality to optimize winter wheat production for bread baking qualities in the southeastern USA.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Interacting sprays'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles