Relevant bibliographies by topics / Double flux schemes

Academic literature on the topic 'Double flux schemes'

Author: Grafiati
Published: 10 December 2022
Last updated: 29 January 2023

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

Select a source type:

Contents

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Double flux schemes.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Double flux schemes"

1

Nikitina, I., A. Polyakov, and D. Voronin. "EXPERIMENTAL MEASURES TO IMPROVE THERMAL CHARACTERISTICS IN DOUBLE-SIDED FACE GRINDING MACHINES." Bulletin of Belgorod State Technological University named after. V. G. Shukhov 7, no. 9 (September 16, 2022): 116–26. http://dx.doi.org/10.34031/2071-7318-2022-7-9-116-126.

Full text
Abstract:
The results of full-scale and computational experiments to improve the thermal characteristics of the machine tool are presented. This can lead to a decrease or achieve symmetry of the resulting thermal deformations. The implementation of four schemes for the redistribution of heat fluxes is considered: the heat flux of the main electric motors, directed under the protective casing of the drive pulley, and the heat flux of the belt drive are removed through special windows in the casing to the environment; jointly with the first scheme of redistribution of heat fluxes, cooling of the ends of the grinding headstocks is provided with the help of an impeller fixed on each drive pulley; jointly with the second scheme, heat flux isolation from the left and right electric motors is provided; heating the ends of the machine tool bed. The first three schemes are implemented at idling of the machine tool; the fourth scheme is implemented when the machine is operating under thermal load. The joint implementation of three schemes makes it possible to reduce the displacement of the right circle at idle by 1.5 times, the left circle practically did not move. The test of the first three circuits during the operation of the machine tool under a thermal load does not reveal significant changes in the thermal characteristics. The implementation of the fourth heat flux redistribution scheme help to compensate for thermal deformations from heating in the central part of the bed and reduce changes in the angular position of the grinding wheels.
APA, Harvard, Vancouver, ISO, and other styles
2

Naumann, A. K., A. Seifert, and J. P. Mellado. "A refined statistical cloud closure using double-Gaussian probability density functions." Geoscientific Model Development 6, no. 5 (October 8, 2013): 1641–57. http://dx.doi.org/10.5194/gmd-6-1641-2013.

Full text
Abstract:
Abstract. We introduce a probability density function (PDF)-based scheme to parameterize cloud fraction, average liquid water and liquid water flux in large-scale models, that is developed from and tested against large-eddy simulations and observational data. Because the tails of the PDFs are crucial for an appropriate parameterization of cloud properties, we use a double-Gaussian distribution that is able to represent the observed, skewed PDFs properly. Introducing two closure equations, the resulting parameterization relies on the first three moments of the subgrid variability of temperature and moisture as input parameters. The parameterization is found to be superior to a single-Gaussian approach in diagnosing the cloud fraction and average liquid water profiles. A priori testing also suggests improved accuracy compared to existing double-Gaussian closures. Furthermore, we find that the error of the new parameterization is smallest for a horizontal resolution of about 5–20 km and also depends on the appearance of mesoscale structures that are accompanied by higher rain rates. In combination with simple autoconversion schemes that only depend on the liquid water, the error introduced by the new parameterization is orders of magnitude smaller than the difference between various autoconversion schemes. For the liquid water flux, we introduce a parameterization that is depending on the skewness of the subgrid variability of temperature and moisture and that reproduces the profiles of the liquid water flux well.
APA, Harvard, Vancouver, ISO, and other styles
3

Naumann, A. K., A. Seifert, and J. P. Mellado. "A refined statistical cloud closure using double-Gaussian probability density functions." Geoscientific Model Development Discussions 6, no. 1 (February 18, 2013): 1085–125. http://dx.doi.org/10.5194/gmdd-6-1085-2013.

Full text
Abstract:
Abstract. We introduce a probability density function (PDF) based scheme to parameterize cloud fraction, average liquid water and liquid water flux in large-scale models, that is developed from and tested against large-eddy simulations and observational data. Because the tails of the PDFs are crucial for an appropriate parameterization of cloud properties, we use a double-Gaussian distribution that is able to represent the observed, skewed PDFs properly. Introducing two closure equations, the resulting parameterization relies on the first three moments of the subgrid variability of temperature and moisture as input parameters. The parameterization is shown to be clearly superior to a single-Gaussian approach in diagnosing the cloud fraction and average liquid water profiles and improves existing double-Gaussian closures. We find that the error of the new parameterization is smallest for a horizontal resolution of about 5–20 km and also depends on the appearance of mesoscale structures that are accompanied by higher rain rates. In combination with simple autoconversion schemes that only depend on the liquid water, the error introduced by the new parameterization is orders of magnitude smaller than the difference between various autoconversion schemes. For the liquid water flux, we introduce a parameterization that is depending on the skewness of the subgrid variability of temperature and moisture and that reproduces the profiles of the liquid water flux well.
APA, Harvard, Vancouver, ISO, and other styles
4

Zhu, Huajun, Xiaogang Deng, Meiliang Mao, Huayong Liu, and Guohua Tu. "Osher Flux with Entropy Fix for Two-Dimensional Euler Equations." Advances in Applied Mathematics and Mechanics 8, no. 4 (May 27, 2016): 670–92. http://dx.doi.org/10.4208/aamm.2014.m469.

Full text
Abstract:
AbstractWe compare in this paper the properties of Osher flux with O-variant and P-variant (Osher-O flux and Osher-P flux) in finite volume methods for the two-dimensional Euler equations and propose an entropy fix technique to improve their robustness. We consider both first-order and second-order reconstructions. For inviscid hypersonic flow past a circular cylinder, we observe different problems for different schemes: A first-order Osher-O scheme on quadrangular grids yields a carbuncle shock, while a first-order Osher-P scheme results in a dislocation shock for high Mach number cases. In addition, a second-order Osher scheme can also yield a carbuncle shock or be unstable. To improve the robustness of these schemes we propose an entropy fix technique, and then present numerical results to show the effectiveness of the proposed method. In addition, the influence of grid aspects ratio, relative shock position to the grid and Mach number on shock stability are tested. Viscous heating problem and double Mach reflection problem are simulated to test the influence of the entropy fix on contact resolution and boundary layer resolution.
APA, Harvard, Vancouver, ISO, and other styles
5

Song, Xiaoliang, and Guang Jun Zhang. "Convection Parameterization, Tropical Pacific Double ITCZ, and Upper-Ocean Biases in the NCAR CCSM3. Part I: Climatology and Atmospheric Feedback." Journal of Climate 22, no. 16 (August 15, 2009): 4299–315. http://dx.doi.org/10.1175/2009jcli2642.1.

Full text
Abstract:
Abstract The role of convection parameterization in the formation of double ITCZ and associated upper-ocean biases in the NCAR Community Climate System Model, version 3 (CCSM3) is investigated by comparing the simulations using the original and revised Zhang–McFarlane (ZM) convection schemes. Ten-year model climatologies show that the simulation with the original ZM scheme produces a typical double ITCZ bias, whereas all biases related to the spurious double ITCZ and overly strong cold tongue in precipitation, sea surface temperature (SST), wind stress, ocean thermocline, upper-ocean currents, temperature, and salinity are dramatically reduced when the revised ZM scheme is used. These results demonstrate that convection parameterization plays a critical role in the formation of double ITCZ bias in the CCSM3. To understand the physical mechanisms through which the modifications of the convection scheme in the atmospheric model alleviate the double ITCZ bias in the CCSM3, the authors investigate the impacts of convection schemes on the atmospheric forcing and feedback in the uncoupled Community Atmospheric Model, version 3 (CAM3). It is shown that the CAM3 simulation with the original ZM scheme also produces a signature of double ITCZ bias in precipitation, whereas the simulation with the revised ZM scheme does not. Diagnostic analyses have identified three factors on the atmospheric side (i.e., the sensitivity of convection to SST, the convection–shortwave flux–SST feedback, and the convection–wind–evaporation–SST feedback) that may contribute to the differences in the coupled simulations.
APA, Harvard, Vancouver, ISO, and other styles
6

Parkes, Ben, Alan Gadian, and John Latham. "The Effects of Marine Cloud Brightening on Seasonal Polar Temperatures and the Meridional Heat Flux." ISRN Geophysics 2012 (May 8, 2012): 1–7. http://dx.doi.org/10.5402/2012/142872.

Full text
Abstract:
Marine cloud brightening (MCB) is one of several proposed solar radiation management (SRM) geoengineering schemes designed to ameliorate some of the undesirable effects of climate change, for example polar ice loss and associated increased sea levels. Satellite measurements over the last 40 years show a general reduction in polar sea ice area and thickness which is attributed to climate change. In our studies, HadGEM1, a fully coupled climate model, is used to predict changes in surface temperatures and ice cover as a result of implementing MCB in a double carbon dioxide concentration atmosphere. The meridional heat flux (MHF) is the mechanism within the earth system for the transport of energy from tropical to polar regions. This poleward transport of heat in a double carbon dioxide atmosphere amplifies the effects in polar regions, where it has a significant impact on both temperatures and ice cover. The results from this work show that MCB is capable of roughly restoring control temperatures and ice cover (where control is defined as 440 ppm carbon dioxide, a predicted 2020 level) in a double carbon dioxide atmosphere scenario. This work presents the first results on the impact of MCB on the MHF and the ability of the MCB scheme to restore the MHF to a control level.
APA, Harvard, Vancouver, ISO, and other styles
7

Bae, Soo Ya, Song-You Hong, and Kyo-Sun Sunny Lim. "Coupling WRF Double-Moment 6-Class Microphysics Schemes to RRTMG Radiation Scheme in Weather Research Forecasting Model." Advances in Meteorology 2016 (2016): 1–11. http://dx.doi.org/10.1155/2016/5070154.

Full text
Abstract:
A method to explicitly calculate the effective radius of hydrometeors in the Weather Research Forecasting (WRF) double-moment 6-class (WDM6) microphysics scheme is designed to tackle the physical inconsistency in cloud properties between the microphysics and radiation processes. At each model time step, the calculated effective radii of hydrometeors from the WDM6 scheme are linked to the Rapid Radiative Transfer Model for GCMs (RRTMG) scheme to consider the cloud effects in radiative flux calculation. This coupling effect of cloud properties between the WDM6 and RRTMG algorithms is examined for a heavy rainfall event in Korea during 25–27 July 2011, and it is compared to the results from the control simulation in which the effective radius is prescribed as a constant value. It is found that the derived radii of hydrometeors in the WDM6 scheme are generally larger than the prescribed values in the RRTMG scheme. Consequently, shortwave fluxes reaching the ground (SWDOWN) are increased over less cloudy regions, showing a better agreement with a satellite image. The overall distribution of the 24-hour accumulated rainfall is not affected but its amount is changed. A spurious rainfall peak over the Yellow Sea is alleviated, whereas the local maximum in the central part of the peninsula is increased.
APA, Harvard, Vancouver, ISO, and other styles
8

Vettoliere, Antonio, and Carmine Granata. "Picoammeters Based on Gradiometric Superconducting Quantum Interference Devices." Applied Sciences 12, no. 18 (September 8, 2022): 9030. http://dx.doi.org/10.3390/app12189030.

Full text
Abstract:
High-sensitivity ac current sensors based on a superconducting quantum interference device have been designed, fabricated and characterized. In particular, double-washer schemes in either parallel or series configurations have been considered. The advantages and the drawbacks of both configurations have been examined by measuring the main features and parameters, such as the flux-to-voltage characteristic, the magnetic field spectral noise and flux-to-current transfer factor. The devices are designed to have similar flux-to-current transfer factors and are fabricated on the same chip to avoid differences in parameters due to the fabrication process. Both devices exhibited a current sensitivity as low as 1–2 pA per bandwidth unit, allowing for their use in ultrahigh-sensitivity applications.
APA, Harvard, Vancouver, ISO, and other styles
9

Payeur, Guillaume, Étienne Artigau, Laurence Perreault Levasseur, and René Doyon. "Correlated Read Noise Reduction in Infrared Arrays Using Deep Learning." Astronomical Journal 163, no. 6 (May 25, 2022): 292. http://dx.doi.org/10.3847/1538-3881/ac69d2.

Full text
Abstract:
Abstract We present a new procedure rooted in deep learning to construct science images from data cubes collected by astronomical instruments using HxRG detectors in low-flux regimes. It improves on the drawbacks of the conventional algorithms to construct 2D images from multiple readouts by using the readout scheme of the detectors to reduce the impact of correlated readout noise. We train a convolutional recurrent neural network on simulated astrophysical scenes added to laboratory darks to estimate the flux on each pixel of science images. This method achieves a reduction of the noise on constructed science images when compared to standard flux-measurement schemes (correlated double sampling, up-the-ramp sampling), which results in a reduction of the error on the spectrum extracted from these science images. Over simulated data cubes created in a low signal-to-noise ratio regime where this method could have the largest impact, we find that the error on our constructed science images falls faster than a 1 / N decay, and that the spectrum extracted from the images has, averaged over a test set of three images, a standard error reduced by a factor of 1.85 in comparison to the standard up-the-ramp pixel sampling scheme. The code used in this project is publicly available on GitHub 7 7 https://github.com/GuillaumePayeur/HxRG-denoiser
APA, Harvard, Vancouver, ISO, and other styles
10

Kumar, Sarvesh, Ricardo Oyarzúa, Ricardo Ruiz-Baier, and Ruchi Sandilya. "Conservative discontinuous finite volume and mixed schemes for a new four-field formulation in poroelasticity." ESAIM: Mathematical Modelling and Numerical Analysis 54, no. 1 (January 2020): 273–99. http://dx.doi.org/10.1051/m2an/2019063.

Full text
Abstract:
We introduce a numerical method for the approximation of linear poroelasticity equations, representing the interaction between the non-viscous filtration flow of a fluid and the linear mechanical response of a porous medium. In the proposed formulation, the primary variables in the system are the solid displacement, the fluid pressure, the fluid flux, and the total pressure. A discontinuous finite volume method is designed for the approximation of solid displacement using a dual mesh, whereas a mixed approach is employed to approximate fluid flux and the two pressures. We focus on the stationary case and the resulting discrete problem exhibits a double saddle-point structure. Its solvability and stability are established in terms of bounds (and of norms) that do not depend on the modulus of dilation of the solid. We derive optimal error estimates in suitable norms, for all field variables; and we exemplify the convergence and locking-free properties of this scheme through a series of numerical tests.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Double flux schemes"

1

Pérez, Arroyo Carlos. "Large eddy simulations of a dual-stream jet with shockcells and noise emission analysis." Thesis, Toulouse, INPT, 2016. http://www.theses.fr/2016INPT0093/document.

Full text
Abstract:
Cette thèse fait référence au bruit de choc généré par des jets sousdétendus simple ou en configuration co-axial. Le bruit de choc est généré par l'interaction entre les structures turbulentes de la couche de cisaillement et le réseaux de cellules de choc développé dans le cône potentiel du jet. Afin d'étudier le bruit choc, simulations à grandes échelles adaptés pour l'aéro-acoustique sont effectué avec des schémas d'ordre élevé qui permet une approche nondissipative et non-dispersive. Les résultats sont analysés et comparés avec des résultats expérimentaux. Notamment, une filtrage hydrodynamique et acoustique est réalisé dans le champ proche pour analyser les modes azimutaux acoustiques et hydrodynamiques. En outre, un analyse basé sur la transformé en ondelettes est mis en oeuvre pour identifier les caractéristiques acoustiques et hydrodynamiques importants des jets supersoniques
This thesis deals with the shock-cell noise generated by under-expanded supersonic jets in single- and dualstream configurations. Shock-cell noise is generated by the interaction between the turbulent structures of the shear-layer and the shock-cell system developed in the potential core of the jet. In order to study shock-cell noise, large eddy simulations adapted to aeroacoustics are carried out using high-order compact schemes that allow for a non-dissipative nondispersive approach. The results are analyzed and compared to experimental results. In particular, an acoustic-hydrodynamic filtering is carried out in the near field in order to analyze the acoustic and hydrodynamic azimuthal modes. Moreover, a wavelet-based analysis is implemented in order to identify the relevant acoustic and hydrodynamic features of the supersonic jets
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Double flux schemes"

1

Zhou, Yingjian, and Wei Chen. "Analysis and Optimization of Low-Voltage and High-Current Matrix Current-Doubler Rectifiers Integrated Magnetic Components." In Advances in Transdisciplinary Engineering. IOS Press, 2022. http://dx.doi.org/10.3233/atde221039.

Full text
Abstract:
All parties favour the half-bridge current-doubling rectifier circuit due to its advantages: small output current pulsation, low switching voltage stress, and high anti-unbalance ability. Further integration of the secondary inductor and the transformer further reduces the size of the converter and dramatically improves the power density. This paper carefully analyzes the existing magnetic integration schemes. Combined with the characteristics of low-voltage and high-current DC converters, the secondary winding in this paper adopts the form of one turn to further reduce the loss so as to adapt to the secondary output of high current. The way the integrated magnetics are matrixed. The secondary side has a higher DC flux offset, and the magnetic core material adopts a magnetic powder core with high saturation magnetic density, which is equivalent to a distributed air gap, which significantly reduces the additional winding loss caused by the air gap diffusion magnetic flux cutting the winding. The winding loss, termination loss, core loss, and distribution parameters of single and matrix integrated magnetic components were compared and analyzed. Focus on optimization analysis. At the same time, it focuses on the influence of matrix on the DC bias and DC loss of the current-doubling rectifier core. At the same time, the leakage inductance and winding loss of the integrated magnetic components are comprehensively considered, and a compromise design is carried out further to improve the power density of the integrated magnetic components.
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Double flux schemes"

1

Husain, Tausif, Iftekhar Hassan, Yilmaz Sozer, Iqbal Husain, and Eduard Muljadi. "Winding schemes for wide constant power range of double stator transverse flux machine." In 2015 IEEE International Electric Machines & Drives Conference (IEMDC). IEEE, 2015. http://dx.doi.org/10.1109/iemdc.2015.7409196.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Edwards, M. G., and H. Zheng. "Double-families of Quasi-Positive Flux-continuous Finite-volume Schemes on Structured and Unstructured Grids." In 11th European Conference on the Mathematics of Oil Recovery. Netherlands: EAGE Publications BV, 2008. http://dx.doi.org/10.3997/2214-4609.20146362.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Feng, Fan, Chunwei Gu, and Xuesong Li. "Discontinuous Galerkin Solution of Three-Dimensional Reynolds-Averaged Navier-Stokes Equations With S-A Turbulence Model." In ASME Turbo Expo 2010: Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-23133.

Full text
Abstract:
In this paper Discontinuous Galerkin Method (DGM) is applied to solve the Reynolds-averaged Navier-Stokes equations and S-A turbulence model equation in curvilinear coordinate system. Different schemes, including Lax-Friedrichs (LF) flux, Harten, Lax and van Leer (HLL) flux and Roe flux are adopted as numerical flux of inviscid terms at the element interface. The gradients of conservative variables in viscous terms are constructed by mixed formulation, which solves the gradients as auxiliary unknowns to the same order of accuracy as conservative variables. The methodology is validated by simulations of double Mach reflection problem and three-dimensional turbulent flowfield within compressor cascade NACA64. The numerical results agree well with the experimental data.
APA, Harvard, Vancouver, ISO, and other styles
4

Celestina, Richard, Spencer Sperling, Louis Christensen, Randall Mathison, Hakan Aksoy, and Jong Liu. "Development of New Single and High-Density Heat-Flux Gauges for Unsteady Heat Transfer Measurements for a Rotating Transonic Turbine." In ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-14527.

Full text
Abstract:
Abstract This paper presents the development and implementation of a new generation of double-sided heat-flux gauges at The Ohio State University Gas Turbine Laboratory (GTL) along with heat transfer measurements for film-cooled airfoils in a single-stage high-pressure transonic turbine operating at design corrected conditions. Double-sided heat flux gauges are a critical part of turbine cooling studies, and the new generation improves upon the durability and stability of previous designs while also introducing high-density layouts that provide better spatial resolution. These new customizable high-density double-sided heat flux gauges allow for multiple heat transfer measurements in a small geometric area such as immediately downstream of a row of cooling holes on an airfoil. Two high-density designs are utilized: Type A consists of 9 gauges laid out within a 5 mm by 2.6 mm (0.20 inch by 0.10 inch) area on the pressure surface of an airfoil, and Type B consists of 7 gauges located at points of predicted interest on the suction surface. Both individual and high-density heat flux gauges are installed on the blades of a transonic turbine experiment for the second build of the High-Pressure Turbine Innovative Cooling program (HPTIC2). Run in a short duration facility, the single-stage high-pressure turbine operated at design-corrected conditions (matching corrected speed, flow function, and pressure ratio) with forward and aft purge flow and film-cooled blades. Gauges are placed at repeated locations across different cooling schemes in a rainbow rotor configuration. Airfoil film-cooling schemes include round, fan, and advanced shaped cooling holes in addition to uncooled airfoils. Both the pressure and suction surfaces of the airfoils are instrumented at multiple wetted distance locations and percent spans from roughly 10% to 90%. Results from these tests are presented as both time-average values and time-accurate ensemble averages in order to capture unsteady motion and heat transfer distribution created by strong secondary flows and cooling flows.
APA, Harvard, Vancouver, ISO, and other styles
5

Hassan, O., and I. Hassan. "Experimental Investigations of the Effect of Scheme Exit Height and Double Row Injection on the Film Cooling Performance of a Micro Tangential Jet Scheme: Part II — Suction Side." In ASME 2015 Power Conference collocated with the ASME 2015 9th International Conference on Energy Sustainability, the ASME 2015 13th International Conference on Fuel Cell Science, Engineering and Technology, and the ASME 2015 Nuclear Forum. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/power2015-49132.

Full text
Abstract:
This paper presents experimental investigations of the effect of scheme exit height and double jet injection on the film cooling performance of a Micro-Tangential-Jet (MTJ) scheme on the suction side of a gas turbine vane using the transient Thermochromic Liquid Crystal (TLC) technique. In part I of the present paper the investigations over the pressure side are presented. The MTJ scheme is a micro-shaped scheme designed so that the micro-sized secondary jet is supplied tangentially to the vane surface. In order to investigate the effect of scheme exit height, one row of the MTJ scheme with exit height of 1.5 hole diameters was investigated and compared with the case of 1.0 hole diameter scheme exit height. Meanwhile, to investigate the effect of double injection, one row of the MTJ scheme in staggered arrangement with one row of fan-shaped scheme was investigated. The investigations were conducted at a blowing ratio, calculated based on the scheme exit area, ranging from 0.25 to 0.625. The average density ratio during the investigations was 0.93, and the Reynolds Number was 1.4E+5, based on the free stream velocity and the main duct hydraulic diameter. The pitch to diameter ratio of the cooling holes is 6.5, and the turbulence intensity during all investigations was 8.5%. The increase in the MTJ scheme exit height did not result in significant change in the Mach number distribution. Moreover, increasing the scheme exit height resulted in enhanced effectiveness performance. The enhanced effectiveness was accompanied with Heat Transfer Coefficient (HTC) ratio augmentation as well. As a result, a reduction in the Net Heat Flux Reduction (NHFR) accompanied increasing the scheme exit height from 1.0 to 1.5 hole diameters. Besides, adding a row of shaped schemes in front of the MTJ scheme result in significant effectiveness reduction, compared to the case of single row injection. The latter was attributed to the presence of the shaped scheme inclination angle that result in enhanced secondary stream loss due to the perpendicular momentum component to the vane surface accompanying the shaped scheme secondary jet.
APA, Harvard, Vancouver, ISO, and other styles
6

Mao, Shuo, Ridge A. Sibold, Stephen Lash, Wing F. Ng, Hongzhou Xu, and Michael Fox. "Experimental Study of the Endwall Heat Transfer of a Transonic Nozzle Guide Vane With Upstream Jet Purge Cooling: Part 1 — Effect of Density Ratio." In ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-14814.

Full text
Abstract:
Abstract Nozzle guide vane platforms often employ complex cooling schemes to mitigate ever-increasing thermal loads on endwall. Understanding the impact of advanced cooling schemes amid the highly complex three-dimensional secondary flow is vital to engine efficiency and durability. This study analyzes and describes the effect of coolant to mainstream blowing ratio, momentum ratio and density ratio for a typical axisymmetric converging nozzle guide vane platform with an upstream doublet staggered, steep-injection, cylindrical hole jet purge cooling scheme. Nominal flow conditions were engine representative and as follows: Maexit = 0.85, Reexit/Cax = 1.5 × 106 and an inlet large-scale freestream turbulence intensity of 16%. Two blowing ratios were investigated, each corresponding to upper and lower engine extrema at M = 3.5 and 2.5, respectively. For each blowing ratio, the coolant to mainstream density ratio was varied between DR = 1.2, representing typical experimental neglect of coolant density, and DR = 1.95, representative of typical engine conditions. An optimal coolant momentum ratio between = 6.3 and 10.2 is identified for in-passage film effectiveness and net heat flux reduction, at which the coolant suppresses and overcomes secondary flows but imparts minimal turbulence and remains attached to endwall. Progression beyond this point leads to cooling effectiveness degradation and increased endwall heat flux. Endwall heat transfer does not scale well with one single parameter; increasing with increasing mass flux for the low density case but decreasing with increasing mass flux of high density coolant. From the results gathered, both coolant to mainstream density ratio and blowing ratio should be considered for accurate testing, analysis and prediction of purge jet cooling scheme performance.
APA, Harvard, Vancouver, ISO, and other styles
7

Torrioli, Guido, Simona Lombardo, Claudio Macculi, Luigi Piro, and Luca Colasanti. "Progress towards a double flux-locked-loop scheme for SQuID readout of TES detector arrays." In SPIE Astronomical Telescopes + Instrumentation, edited by Tadayuki Takahashi, Jan-Willem A. den Herder, and Mark Bautz. SPIE, 2014. http://dx.doi.org/10.1117/12.2056317.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

He, J., and B. Q. Zhang. "The Local Analytic Numerical Method for the Double Vortex Combustor Flow." In ASME 1985 Beijing International Gas Turbine Symposium and Exposition. American Society of Mechanical Engineers, 1985. http://dx.doi.org/10.1115/85-igt-110.

Full text
Abstract:
A new hyperbolic function discretization equation for two dimensional Navier-Stokes equation in the stream function vorticity from is derived. The basic idea of this method is to integrat the total flux of the general variable ϕ in the differential equations, then incorporate the local analytic solutions in hyperbolic function for the one-dimensional linearized transport equation. The hyperbolic discretization (HD) scheme can more accurately represent the conservation and transport properties of the governing equation. The method is tested in a range of Reynolds number (Re=100~2000) using the viscous incompressible flow in a square cavity. It is proved that the HD scheme is stable for moderately high Reynolds number and accurate even for coarse grids. After some proper extension, the method is applied to predict the flow field in a new type combustor with air blast double-vortex and obtained some useful results.
APA, Harvard, Vancouver, ISO, and other styles
9

Torrioli, G., P. Bastia, L. Piro, C. Macculi, L. Colasanti, Betty Young, Blas Cabrera, and Aaron Miller. "A Double Flux Locked Loop Scheme For SQUID Readout Of TES Detector Arrays Using The FDM Technique." In THE THIRTEENTH INTERNATIONAL WORKSHOP ON LOW TEMPERATURE DETECTORS—LTD13. AIP, 2009. http://dx.doi.org/10.1063/1.3292394.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Torrioli, Guido, Paolo Bastia, Luigi Piro, Claudio Macculi, and Luca Colasanti. "A cryo-amplifier working in a double loop-flux locked loop scheme for SQUID readout of TES detectors." In SPIE Astronomical Telescopes + Instrumentation, edited by Monique Arnaud, Stephen S. Murray, and Tadayuki Takahashi. SPIE, 2010. http://dx.doi.org/10.1117/12.856430.

Full text
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Double flux schemes' for particular source types:
Journal articles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography