Journal articles: 'Recirculating'

1

Budzianowski, Wojciech. "Thermal and bifurcation characteristics of heat-recirculating conversion of gaseous fuels." Archives of Thermodynamics 31, no. 2 (July 1, 2010): 63–75. http://dx.doi.org/10.2478/v10173-010-0009-6.

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Thermal and bifurcation characteristics of heat-recirculating conversion of gaseous fuelsThe paper investigates the possibility of utilisation of heat-recirculating systems for fuel conversions having low net thermal effect. The experimental part is conducted with an electrically heated heat exchanger. It is shown that heat-recirculating systems can operate under superadiabatic conditions. Their thermal characteristics are provided by means of the dependencies of heat recirculation ratio on process parameters. Further, the heat-recirculating catalytic combustion system is characterised via combustion bifurcation diagrams. The similarities and differences of both those heat-recirculating systems are qualitatively compared and explained. Bifurcation characteristics proves to be useful tools in concise description of practical complex heat-recirculating fuel conversion systems in energy generation.

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Young, Alan J., Wendy L. Marston, Mark Dessing, Lisbeth Dudler, and Wayne R. Hein. "Distinct Recirculating and Non-Recirculating B-Lymphocyte Pools in the Peripheral Blood Are Defined by Coordinated Expression of CD21 and L-Selectin." Blood 90, no. 12 (December 15, 1997): 4865–75. http://dx.doi.org/10.1182/blood.v90.12.4865.

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Abstract The continual recirculation of lymphocytes between the blood, tissues, and lymph is essential for the coordination and dissemination of immune responses. We have compared the functional and phenotypic properties of lymphocytes isolated from blood and lymph, the two major migratory populations. Lymph-borne lymphocytes migrated readily into the lymphatic recirculation pathway, but greater than one third of all peripheral blood lymphocytes (PBLs) were excluded from the lymphatic circuit and showed an enhanced migration to the spleen. Phenotypic analysis showed that most non-recirculating PBLs were B cells. The migration competence of B cells correlated with the surface expression of CD21 and L-selectin; recirculating B cells expressed both of these molecules, whereas non-recirculating B cells lacked both antigens. These results establish that blood contains distinct pools of lymphocytes that differ in their recirculation competence. Clearly, blood sampling is not an efficient method to directly measure the status of the recirculating immune system, and implies important constraints and restrictions in the interpretation of experimental or clinical data that include phenotypic and quantitative analyses of blood lymphocytes.

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Young, Alan J., Wendy L. Marston, Mark Dessing, Lisbeth Dudler, and Wayne R. Hein. "Distinct Recirculating and Non-Recirculating B-Lymphocyte Pools in the Peripheral Blood Are Defined by Coordinated Expression of CD21 and L-Selectin." Blood 90, no. 12 (December 15, 1997): 4865–75. http://dx.doi.org/10.1182/blood.v90.12.4865.4865_4865_4875.

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The continual recirculation of lymphocytes between the blood, tissues, and lymph is essential for the coordination and dissemination of immune responses. We have compared the functional and phenotypic properties of lymphocytes isolated from blood and lymph, the two major migratory populations. Lymph-borne lymphocytes migrated readily into the lymphatic recirculation pathway, but greater than one third of all peripheral blood lymphocytes (PBLs) were excluded from the lymphatic circuit and showed an enhanced migration to the spleen. Phenotypic analysis showed that most non-recirculating PBLs were B cells. The migration competence of B cells correlated with the surface expression of CD21 and L-selectin; recirculating B cells expressed both of these molecules, whereas non-recirculating B cells lacked both antigens. These results establish that blood contains distinct pools of lymphocytes that differ in their recirculation competence. Clearly, blood sampling is not an efficient method to directly measure the status of the recirculating immune system, and implies important constraints and restrictions in the interpretation of experimental or clinical data that include phenotypic and quantitative analyses of blood lymphocytes.

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4

LAZA, EVELINE ANDA, IOAN LADISLAU CABA, GHEORGHE STROESCU, ANIŞOARA PĂUN, CARMEN BĂLȚATU, A. ZAICA, and A. A. ZAICA. "STUDIES AND RESEARCH REGARDING THE UNITARY ENERGY CONSUMPTION OF A RECIRCULATING AQUACOL SYSTEM." "Annals of the University of Craiova - Agriculture Montanology Cadastre Series " 51, no. 2 (December 20, 2020): 332–36. http://dx.doi.org/10.52846/aamc.2021.02.40.

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This paper aims to highlight the consumption of electricity and caloric energy consumed by a recirculating aquaculture system for the growth of aquatic life. The energy needed to operate a recirculating aquaculture system for fish farming is divided into two categories, namely the electricity needed to operate various technological equipment, the main equipment in a recirculating aquaculture system that uses electricity being recirculation pumps, mechanical filters (some types), UV sterilization facilities and aeration systems. The second category of energy consumed is the caloric energy required for heating / cooling the water in the system and the hall.

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5

Tsui, Yeng-Yung, and Chia-Kang Wang. "Calculation of Laminar Separated Flow in Symmetric Two-Dimensional Diffusers." Journal of Fluids Engineering 117, no. 4 (December 1, 1995): 612–16. http://dx.doi.org/10.1115/1.2817311.

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This study is concerned with numerical analysis of laminar separated flow in symmetric, two-dimensional, straight-walled diffusers. With Reynolds numbers Re = 56 and 114 and expansion ratios ER = 3 and 4, totally, there are four cases considered. At the low Reynolds number and the low expansion ratio the flow in the diffuser is nearly symmetric to the center line, irrespective of the diffusion angle. As Reynolds number or expansion ratio increases, a large recirculation region forms at one side wall and a small one at the other side. For the case with Re = 114 and ER = 4 the small recirculating flow disappears at small diffusion angles and a third recirculating flow appear in the same side of the small main recirculation region for large diffusion angles. The pressure recovery reaches its peak value somewhere downstream of the reattachment point of the large recirculating flow. The effectiveness of the diffuser deteriorates as the diffusion angle increases, apart from that at Re = 56 the effectiveness increases from θ = 15 to 30 deg. Symmetric flow solutions can be obtained by incorporating a symmetric relaxation method. The pressure recovery is higher for the symmetric flow than that for the asymmetric flow owing to the weaker recirculating strength in the former.

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Ebeling, James M. "Engineering Aspects of Recirculating Aquaculture Systems." Marine Technology Society Journal 34, no. 1 (January 1, 2000): 68–78. http://dx.doi.org/10.4031/mtsj.34.1.8.

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Intensive recirculating aquaculture systems utilizing water recirculation and pure oxygen injection are examined in terms of the individual unit processes that are required to handle the wastes generated by fish at stocking densities as high as 120‐150 kg/m3. These unit processes include solid waste removal, nitrification of ammonia and nitrite, aeration or oxygenation, carbon dioxide removal, and control and monitoring systems. Overall system integration is reviewed and an example of a research/commercial intensive recirculating system is presented.

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Wang, Wei, Wuli Chu, Haoguang Zhang, and Yanhui Wu. "Experimental study of self-recirculating casing treatment in a subsonic axial flow compressor." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 230, no. 8 (October 10, 2016): 805–18. http://dx.doi.org/10.1177/0957650916673266.

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Parametric studies of recirculating casing treatment were experimentally performed in a subsonic axial flow compressor. The recirculating casing treatment was parameterized with injector throat height, injection position, and circumferential coverage percentage. Eighteen recirculating casing treatments were tested to study the effects on compressor stability and on the compressor overall performance at three blade speeds. The profiles of recirculating casing treatment were optimized to minimize the losses generated by air recirculation. In the experiment, the stalling mass flow rate, total pressure ratio, and adiabatic efficiency of the compressor were measured to study the steady-state effects on the compressor performance of recirculating casing treatments, and static pressure disturbances on the casing wall were monitored to study the influence on stall dynamics. Results indicate that both the compressor stability and overall performance can be improved through recirculating casing treatment with appropriate geometrical parameters for all the test speeds. The influence on stall margin of one geometric parameter often depends on the choice of others, i.e. the interaction effects exist. In general, the recirculating casing treatment with a moderate injector throat and a large circumferential coverage is the optimal choice to enhance compressor stability. The injector of recirculating casing treatment should be placed upstream of the blade tip leading edge and the injector throat height should be lower than four times the rotor tip gap for the benefits of compressor efficiency. At 71% speed, the blade tip loading is decreased through recirculating casing treatment at the operating condition of near peak efficiency and increased near stall. Moreover, the outlet absolute flow angle is reduced in the tip region and enhanced at lower blade spans for both operating conditions. The stall inceptions are not changed with the implementation of recirculating casing treatment for all the test speeds, but the stall patterns are altered at 33% and 53% speeds, i.e. the stall with two cells is detected in the recirculating casing treatment compared with the solid casing with only one stall cell.

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8

Nag, D., and A. Datta. "On the eddy characteristics of laminar axisymmetric flows through confined annular geometries with inward expansion." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 221, no. 2 (February 1, 2007): 213–26. http://dx.doi.org/10.1243/0954406jmes428.

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In this paper, laminar flows through axisymmetric confined annular geometries with sudden expansions have been studied numerically using a third-order accurate upstream biased quadratic scheme to investigate the recirculating eddy characteristics, following the expansion, in terms of recirculation length and eddy intensity. Two variations of annular geometry have been considered. In the first geometry, a smaller annulus abruptly expands inwardly into a larger one, whereas in the second case an abrupt inward expansion of the smaller annulus leads to a coaxial pipe. Fully developed inflow has been observed to separate immediately after the expansion plane forming a recirculating eddy. The variations in the size and intensity of the recirculating eddy are studied at different Reynolds numbers and expansion ratio for both the geometries. The effect of the presence of an inner solid wall after the expansion plane on the behaviour of the eddy is investigated. A secondary wall recirculation has been observed under specific flow situations in both the geometries. The characteristics of the secondary eddy have also been analysed and compared.

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9

Naeimifard, Alireza, and Ali Ghaffari. "COMPUTATIONAL MODEL OF RECIRCULATING LYMPHOCYTES." Journal of Biological Systems 23, no. 01 (March 2015): 93–114. http://dx.doi.org/10.1142/s0218339015500060.

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Lymphocyte recirculation plays an important role in controlling the spread of both pathogenic infections and tumor-producing cancer cells in the human body. We present a mathematical and computational framework that allows investigation of recirculating lymphocytes and estimation of model parameters using a genetic algorithm. The framework allows estimating parameters using data obtained from experiments performed in laboratory studies of rats as well as clinical studies of human subjects. Our computational model allows improved understanding of these data. Mathematical models enable investigators to obtain a quantitative picture of immune system kinetics and diversity in human health and disease outcomes. Our data-driven systems biology and immunological modeling approach contributes to a growing understanding of the dynamics of lymphocyte recirculation.

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10

Fuller, Alexander M., Thomas W. N. Haine, and Erik Kvaleberg. "Recirculating flow in a basin with closed f/h contours." Journal of Marine Research 77, no. 1 (January 1, 2019): 267–96. http://dx.doi.org/10.1357/002224019826887344.

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A general circulation model is used to study the time evolution of a rotating, weakly baroclinic fluid in a basin with sloping sidewalls. Contours of f/h, where f is the Coriolis parameter and h is the depth of the fluid, are closed in this model. The fluid is forced by a localized source of positive vorticity. The initial response is a narrow, recirculating cell that resembles a β-plume modified by bathymetry. Such cells have been found in previous studies and have been linked to the recirculation cells observed in the subpolar North Atlantic. However, this is not a steady solution in this basin with closed f/h contours, and the circulation evolves into a gyre that encircles the basin. The time at which this transition occurs depends on the Rossby number, with higher Rossby numbers transitioning earlier. Based on the budget of potential vorticity, an argument is made that the western boundary is not long enough to drain significant vorticity from the flow and therefore a bathymetric β-plume is not a steady solution. A similar argument suggests that the Labrador Sea cannot sustain steady, linear, barotropic recirculations either. We speculate that the observed recirculations depend on inertial separation at sharp bathymetric gradients to break the assumption of linearity, which leads to significant viscous dissipation.

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11

Geldenhuys, R., N. Chi, I. Tafur Monroy, A. M. J. Koonen, H. J. S. Dorren, F. W. Leuschner, G. D. Khoe, S. Yu, and Z. Wang. "Multiple recirculations through Crosspoint switch fabric for recirculating optical buffering." Electronics Letters 41, no. 20 (2005): 1136. http://dx.doi.org/10.1049/el:20052568.

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12

Seabrook, Tim J., Wayne R. Hein, Lisbeth Dudler, and Alan J. Young. "Splenectomy selectively affects the distribution and mobility of the recirculating lymphocyte pool." Blood 96, no. 3 (August 1, 2000): 1180–83. http://dx.doi.org/10.1182/blood.v96.3.1180.

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Abstract The spleen plays a major role in immune surveillance, but the impact that splenectomy exerts on the immune competence of an individual is not fully resolved. Here we show that neonatal splenectomy in sheep does not abrogate the development of a large, nonrecirculating pool of lymphocytes and that it has no effect on the acquisition of a normal blood lymphocyte profile. Splenectomy did, however, result in a significant decrease in blood residency time of recirculating lymphocytes and in an enhanced accumulation of recirculating lymphocytes in lymph nodes. Furthermore, nonrecirculating peripheral blood lymphocytes were less likely to migrate to the lung, possibly because of saturation of the marginal pool by recirculating lymphocytes. Although splenectomy has little effect on the development or distribution of lymphocyte subsets in blood and lymph, it has marked effects on the rate of recirculation of lymphocytes, which may have significant implications for peripheral immune surveillance in patients who undergo splenectomy.

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13

Seabrook, Tim J., Wayne R. Hein, Lisbeth Dudler, and Alan J. Young. "Splenectomy selectively affects the distribution and mobility of the recirculating lymphocyte pool." Blood 96, no. 3 (August 1, 2000): 1180–83. http://dx.doi.org/10.1182/blood.v96.3.1180.015k24_1180_1183.

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The spleen plays a major role in immune surveillance, but the impact that splenectomy exerts on the immune competence of an individual is not fully resolved. Here we show that neonatal splenectomy in sheep does not abrogate the development of a large, nonrecirculating pool of lymphocytes and that it has no effect on the acquisition of a normal blood lymphocyte profile. Splenectomy did, however, result in a significant decrease in blood residency time of recirculating lymphocytes and in an enhanced accumulation of recirculating lymphocytes in lymph nodes. Furthermore, nonrecirculating peripheral blood lymphocytes were less likely to migrate to the lung, possibly because of saturation of the marginal pool by recirculating lymphocytes. Although splenectomy has little effect on the development or distribution of lymphocyte subsets in blood and lymph, it has marked effects on the rate of recirculation of lymphocytes, which may have significant implications for peripheral immune surveillance in patients who undergo splenectomy.

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14

Benaissa, A., M. F. Bardon, J. E. D. Gauthier, F. Anselmet, and E. Ruffïn. "RECIRCULATION OF CONFINED VARIABLE DENSITY TURBULENT JETS." Transactions of the Canadian Society for Mechanical Engineering 27, no. 4 (December 2004): 279–94. http://dx.doi.org/10.1139/tcsme-2003-0015.

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An investigation of recirculating characteristics of circular turbulent confined jets with large density variations is presented. This numerical study aims at testing analytical predictions associated with the Craya-Curtet number. It investigates also its effect on the dynamic field and recirculation. It appears that for different density (He-air, CO2-air) and geometry ratios, the non-isothermal Craya-Curtet number [1] is not sufficient to describe the flow pattern or predict its recirculation. Depending on the momentum, aspect and density ratios of the flow, the centre of the recirculating flow (the eye) tends to reach the initial (non-self-preserving) region of the jet and influences the development of the jet. As a consequence, predictions are not in agreement with theory. The reason is that initial conditions do not satisfy the hypothesis used in the prediction of recirculation theory. Calculations are performed in three configurations: CO2, air and He. These configurations are fully developed pipe jets evolving in an air secondary turbulent flow. Validations are performed using experimental data [2] obtained in similar configurations for the three gases.

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15

Tang, Ai Kun, Jian Feng Pan, Xia Shao, and Yang Xian Liu. "Numerical Study on Combustion Performance Comparison of Premixed Methane-Air in Micro-Combustors with and without Heat Recirculating Channel." Applied Mechanics and Materials 394 (September 2013): 179–84. http://dx.doi.org/10.4028/www.scientific.net/amm.394.179.

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Recently£¬research interests of micro-power generation devices which are based on micro-combustion process have been stimulated by the persistent breakthrough of MEMS techniques. A new type micro-heat recirculating combustor was presented in this paper, and the computation model for premixed methane-air was established which adopting a skeletal reaction mechanism. Combustion characteristics both in heat recirculating combustor and single-channel combustor are analyzed which containing the flame shape, location and temperature at the same simulation conditions. It is found that not only the flame location can be better fixed by heat recirculation measure, but although the flame temperature can be raised for some degrees when compared to the single channel combustor. These results provide some useful information for the design of micro-scale combustors.

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McCreanor, P. T., and D. R. Reinhart. "Hydrodynamic modeling of leachate recirculating landfills." Water Science and Technology 34, no. 7-8 (October 1, 1996): 463–70. http://dx.doi.org/10.2166/wst.1996.0655.

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Leachate recirculation is an emerging technology for the enhanced stabilization of active landfills and in-situ treatment of problematic landfills. A variety of researcher have documented the benefits of increasing landfill moisture content and liquid movement through the fill. However, little work has addressed the hydrodynamic characteristics of the recirculating landfill, specifically the effect of leachate flow rate and waste characteristics upon leachate routing. This paper presents the results of mathematical modeling of the horizontal infiltration trench and vertical infiltration well, two commonly employed leachate application methods. The results of transient unsaturated flow modeling are detailed.

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Elias, Luis R., and Gerald Ramian. "Recirculating Electrostatic Accelerators." IEEE Transactions on Nuclear Science 32, no. 5 (1985): 1732–35. http://dx.doi.org/10.1109/tns.1985.4333705.

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Ingham, D. B., D. J. Keen, P. J. Heggs, and B. R. Morton. "Recirculating pipe flows." Journal of Fluid Mechanics 213, no. -1 (April 1990): 443. http://dx.doi.org/10.1017/s0022112090002397.

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19

Ge, Bing, Shu Sheng Zang, and Pei Qing Guo. "Investigation on Non-Premixed Swirling Flame in a Multi-Hole Burner." Advanced Materials Research 347-353 (October 2011): 2428–31. http://dx.doi.org/10.4028/www.scientific.net/amr.347-353.2428.

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This paper focuses on investigating the flow structures in a multi-hole swirl burner. Using the Particle Image Velocimetry(PIV) technique, the experiment measured the velocity distributions of the swirling flame in a muti-hole burner. The experiments show that there is a central recirculation zone (CRZ) in the middle of the flow field, and two counter-rotating vortices exist along the centerline symmetrically. With fuel jet increase: the width of recirculating zone and axial mean velocity peaks changes little; length of recirculation zone and the biggest reverse flow velocity increases; the expansion angle of swirling jet increase at first, and then changes little; axial non-uniform coefficient of outlet reduces at first, and then increases. With airflow velocity increase: axial mean velocity peaks increase; the dimension of recirculating zone and the expansion angle of swirling jet are unchanged; axial non-uniform coefficient of outlet increases.The data from this experiment is helpful for optimization of the swirl burner design, and can be established as benchmarks for the development and validation of swirl combustion numerical simulations.

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Hammad, Khaled J. "Suddenly expanding recirculating and non-recirculating viscoplastic non-newtonian flows." Journal of Visualization 18, no. 4 (March 12, 2015): 655–67. http://dx.doi.org/10.1007/s12650-015-0279-9.

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21

GREER, G. GORDON, FRANCES NATTRESS, BRYAN DILTS, and LYNDA BAKER. "Bacterial Contamination of Recirculating Brine Used in the Commercial Production of Moisture-Enhanced Pork†." Journal of Food Protection 67, no. 1 (January 1, 2004): 185–88. http://dx.doi.org/10.4315/0362-028x-67.1.185.

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In a commercial process for the production of moisture-enhanced pork, boneless pork loins were conveyed through a recirculating injection apparatus, and brine (sodium phosphate, sodium chloride, and lemon juice solids) was pumped into the meat through banks of needles inserted automatically into the upper surfaces of cuts. Brine samples were collected at intervals during the production process and analyzed to determine the total plate count and the numbers of lactic acid bacteria, pseudomonads, Brochothrix thermosphacta, and Enterobacteriaceae. Listeria monocytogenes numbers in the brine were determined using a PCR with primers for the hemolysin gene in combination with a most probable numbers determination. Maximum numbers of bacteria (log CFU/ml) recovered from the brine after 2.5 h of recirculation were as follows: total plate count, 4.50; lactic acid bacteria, 2.99; pseudomonads, 3.95; B. thermosphacta, 2.79; and enterics, 3.01. There was an increase in the number of L. monocytogenes in the recirculating brine with time, reaching a maximum of 2.34 log CFU/100 ml after 2.5 h of moisture-enhanced pork production. Thus, recirculating brines can harbor large populations of spoilage bacteria and L. monocytogenes and are an important source of contamination for moisture-enhanced pork.

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22

Kawase, Motoyuki, and Aldo Rona. "Numerical Optimization of a Stall Margin Enhancing Recirculation Channel for an Axial Compressor." Fluids 4, no. 2 (May 11, 2019): 88. http://dx.doi.org/10.3390/fluids4020088.

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A proof of concept is provided by computational fluid dynamic simulations of a new recirculating type casing treatment. This treatment aims at extending the stable operating range of highly loaded axial compressors, so to improve the safety of sorties of high-speed, high-performance aircraft powered by high specific thrust engines. This casing treatment, featuring an axisymmetric recirculation channel, is evaluated on the NASA rotor 37 test case by steady and unsteady Reynolds Averaged Navier Stokes (RANS) simulations, using the realizable k-ε model. Flow blockage at the recirculation channel outlet was mitigated by chamfering the exit of the recirculation channel inner wall. The channel axial location from the rotor blade tip leading edge was optimized parametrically over the range −4.6% to 47.6% of the rotor tip axial chord c z . Locating the channel at 18.2% c z provided the best stall margin gain of approximately 5.5% compared to the untreated rotor. No rotor adiabatic efficiency was lost by the application of this casing treatment. The investigation into the flow structure with the recirculating channel gave a good insight into how the new casing treatment generates this benefit. The combination of stall margin gain at no rotor adiabatic efficiency loss makes this design attractive for applications to high-speed gas turbine engines.

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Thompson, B. E., and J. H. Whitelaw. "Characteristics of a trailing-edge flow with turbulent boundary-layer separation." Journal of Fluid Mechanics 157 (August 1985): 305–26. http://dx.doi.org/10.1017/s0022112085002397.

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Experimental techniques, including flying-hot-wire anemometry, have been used to determine the pressure and velocity characteristics of a flow designed to simulate the trailing-edge region of an airfoil at high angle of attack. Emphasis is placed on the region of recirculating flow and on the downstream wake. It is shown that the effect of this recirculation is large even though the details of the flow within it may be unimportant. Normal stresses and cross-stream pressure gradients are important immediately upstream and downstream of the recirculating flow and are associated with strong streamline curvature. The relative importance of the terms in the transport equations for mean momentum and turbulence energy are quantified and the implications for procedures which solve potential-flow and boundary-layer equations and for alternative calculation methods are discussed.

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Neverov, Evgeniy, Igor Korotkiy, and Ilya Prib. "Recirculating carbon dioxide refrigeration unit for freezing food." E3S Web of Conferences 311 (2021): 09007. http://dx.doi.org/10.1051/e3sconf/202131109007.

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The article describes the development process of a refrigeration unit using carbon dioxide as a refrigerant. A feature of the plant is the possibility of recirculating carbon dioxide. The authors substantiate the use of the natural substance CO2 as a refrigerant and consider the prospects for using the refrigerant R744. The efficiency of the cycle of a one-stage subcritical refrigeration unit is analyzed. The authors have designed a recirculating carbon dioxide refrigeration unit based on the traditional subcritical cycle. The essential and auxiliary components of the refrigeration machine were presented and described. The developed scheme allows freezing food products by direct contact of the product with snow-like carbon dioxide. After that, the sublimation process takes place in the freezing chamber and the gas-liquid mixture is sent through the liquid separator for recirculation. The article describes the operation of the system diagram, the principle of operation, and the purpose of the elements of automation and regulation.

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Ngosong, Christopher, Moshe T. Halpern, Joann K. Whalen, and Donald L. Smith. "Purslane (Portulaca oleracea L.) has potential for desalinizing greenhouse recirculation water." Canadian Journal of Plant Science 93, no. 5 (September 2013): 961–64. http://dx.doi.org/10.4141/cjps2012-271.

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Ngosong, C., Halpern, M. T., Whalen, J. K. and Smith, D. L. 2013. Purslane ( Portulaca oleracea L.) has potential for desalinizing greenhouse recirculation water. Can. J. Plant Sci. 93: 961–964. Recirculating fertigation solutions improves the environmental sustainability of hydroponics-based vegetable production in Canada. Purslane is an edible halophyte with proported medicinal benefits that could absorb excess salts from recirculation water. It grew well in hydroponic solutions with up to 1000 mg NaCl L−1. Greatest Na absorption occurred during earlier vegetative growth.

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Claveau-Mallet, Dominique, Félix Lida, and Yves Comeau. "Improving phosphorus removal of conventional septic tanks by a recirculating steel slag filter." Water Quality Research Journal 50, no. 3 (February 13, 2015): 211–18. http://dx.doi.org/10.2166/wqrjc.2015.045.

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The objective of this project was to increase the phosphorus (P) retention capacity of a conventional septic tank by adding a recirculating slag filter. Two recirculation modes and recirculation ratios from 5 to 50% were tested in the laboratory with reconstituted domestic wastewater. The best system was recirculation from the end to the inlet of the second compartment of a septic tank with a 50% recirculation ratio in the slag filter, achieving 4.2 and 1.9 mg P/L at the effluent for total phosphorus (TP) and orthophosphate (o-PO4), respectively, and a pH of 8.8. The calculated size of the slag filter for a two-bedroom house application was 1,875 kg for an expected lifetime of 2 years. The 1 mg P/L level goal was not reached, but P precipitation may be favoured by the relatively high effluent pH reaching the infiltration bed.

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Arai, N., M. Shinoda, and S. W. Churchill. "THE CHARACTERISTICS OF A HEAT-RECIRCULATING CERAMIC BURNER." Transactions of the Canadian Society for Mechanical Engineering 23, no. 1B (May 1999): 147–58. http://dx.doi.org/10.1139/tcsme-1999-0010.

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An experimental burner of the heat-recirculating type was constructed and its thermal characteristics were investigated for methane-air fuel-lean combustion. Longitudinal temperature distributions of air and burned gas flowing in the passes of the burner were determined by means of both experimental measurements and numerical simulations. Using the heat recirculation rate and the thermal efficiency as criteria for the heat transfer performance of the burner, the optimal design of the burner was examined in terms of a chemical parameter (the equivalence ratio), a fluid-mechanical parameter (the Reynolds number), and two geometrical parameters (the aspect ratio and the number of passes).

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Hürlimann, M. D., W. N. Hardy, A. J. Berlinsky, and R. W. Cline. "Recirculating cryogenic hydrogen maser." Physical Review A 34, no. 2 (August 1, 1986): 1605–8. http://dx.doi.org/10.1103/physreva.34.1605.

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29

Tufet, Marta. "Immunosurveillance by recirculating HSPCs." Nature Reviews Immunology 8, no. 1 (January 2008): 2. http://dx.doi.org/10.1038/nri2242.

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30

Mayer, Robert. "4818384 Recirculating sand filter." Environment International 16, no. 4-6 (January 1990): IV. http://dx.doi.org/10.1016/0160-4120(90)90054-a.

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31

Martin, A. R., C. Saltiel, and W. Shyy. "Heat Transfer Enhancement With Porous Inserts in Recirculating Flows." Journal of Heat Transfer 120, no. 2 (May 1, 1998): 458–67. http://dx.doi.org/10.1115/1.2824271.

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This investigation explores the use of porous inserts for heat transfer enhancement in recirculating flows, specifically flow over a backward-facing step. Numerical computations are performed for laminar flow with high porosity inserts, which are composed of small-diameter (150 μm) silicon carbide fibers aligned transverse to the streamwise flow. The inserts are varied in length and porosity in order to determine the most favorable combinations of maximum temperature reduction and head loss penalty. In general, the porous inserts reduce or eliminate the lower wall recirculation zone; however, in some cases the recirculation zone is lengthened if the inserts are short and extremely porous. Excellent heat transfer characteristics are shown within the inserts themselves due to the high-conductivity fiber material. Non-Darcy effects are shown to be important primarily as the porosity is increased. Deviation from local thermodynamic conditions between the inserts and the fluid is most apparent for the shortest inserts considered.

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Roy, Christiane, Richard Auger, and Robert Chénier. "Use of non woven textile in intermittent filters." Water Science and Technology 38, no. 3 (August 1, 1998): 159–66. http://dx.doi.org/10.2166/wst.1998.0198.

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Intermittent filters are widely used in North America for on-site wastewater treatment. However, availability or transportation of the treatment medium can become a limiting factor. The use of non-woven textile coupons, a light, and compressible material, to replace the sand or gravel has been tested. Test columns containing textile coupons over a height of 90 cm were operated at hydraulic loading rates (HLR) of 20 to 60 cm/d, with or without recirculation. During the eighteen months test period, the two most efficient columns, single pass (HLR = 20 cm/d) and recirculating (HLR = 60 cm/d), met treatment goals of 10 mg/l biological oxygen demand (BOD5) and total suspended solids (TSS). Detailed analysis of water quality at different depths and HLRs indicated that water detention time in the coupons might be a factor in organic matter removal. A new filter configuration was then developed to take advantage of this feature; it comprised three hydraulically independent layers of coupons. The new column was tested in the recirculating mode and in the single pass mode at HLRs of 123 and 188 cm/d respectively for six months. In both cases, BOD5 values at the effluent were below 10 mg/l; in the recirculation mode, TSS values were below 15 mg/l.

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Lasnier, Joseph M., David H. Ingbar, Ethan P. Carter, Kirk Wilson, Scott McKnite, Keith G. Lurie, and O. Douglas Wangensteen. "Perfusion technique determines alveolar fluid resorption rate in the isolated perfused rat lung." Journal of Applied Physiology 84, no. 2 (February 1, 1998): 740–45. http://dx.doi.org/10.1152/jappl.1998.84.2.740.

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Lasnier, Joseph M., David H. Ingbar, Ethan P. Carter, Kirk Wilson, Scott McKnite, Keith G. Lurie, and O. Douglas Wangensteen.Perfusion technique determines alveolar fluid resorption rate in the isolated perfused rat lung. J. Appl. Physiol. 84(2): 740–745, 1998.—The isolated perfused lung (IPL) preparation is a well-established model for the study of alveolar epithelial sodium transport. We noted that preparations of normal fluid-filled rat lungs with recirculated perfusate reproducibly lost weight, whereas preparations in which the perfusate was discarded after a single pass through the lungs had a variable and lesser weight change. To confirm this, we performed IPL experiments by using male Sprague-Dawley specific-pathogen-free rats (175–225 g). In 10 IPLs, perfusate initially was discarded after passing through the lungs and then was recirculated continuously. During the single-pass period, the rate of weight change was +0.7 ± 2.0 mg/min compared with −9.0 ± 1.3 mg/min for the recirculating period. Adenosine 3′,5′-cyclic monophosphate (cAMP) accumulated during recirculation. The weight loss induced by recirculation was reproduced by perfusion with 8-bromoadenosine 3′,5′-cyclic monophosphate or terbutaline in single-pass fashion and blocked when the kinase inhibitor H-8 or phosphodiesterase was present in the recirculating perfusate. In summary, perfusate recirculation in the IPL stimulates fluid resorption at least partially via cAMP. This should be factored into the design and interpretation of IPL experiments.

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England, Ellen, Mark W. Fitch, Melanie Mormile, and Michael Roberts. "Toluene removal in membrane bioreactors under recirculating and non-recirculating liquid conditions." Clean Technologies and Environmental Policy 7, no. 4 (November 2005): 259–69. http://dx.doi.org/10.1007/s10098-005-0014-7.

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Davidson, P. A. "Global stability of two-dimensional and axisymmetric Euler flows." Journal of Fluid Mechanics 276 (October 10, 1994): 273–305. http://dx.doi.org/10.1017/s0022112094002569.

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This paper is concerned with the stability of steady inviscid flows with closed streamlines. In increasing order of complexity we look at two-dimensional planar flows, poloidal (r, z) flows, and swirling recirculating flows. In each case we examine the relationship between Arnol’d's variational approach to stability, Moffatt's magnetic relaxation technique, and a more recent relaxation procedure developed by Valliset al.We start with two-dimensional (x, y) flows. Here we show that Moffatt's relaxation procedure will, under a wide range of circumstances, produce Euler flows which are stable. The physical reasons for this are discussed in the context of the well-known membrane analogy. We also show that there is a close relationship between Hamilton's principle and magnetic relaxation. Next, we examine poloidal flows. Here we find that, by and large, our planar results also hold true for axisymmetric flows. In particular, magnetic relaxation once again provides stable Euler flows. Finally, we consider swirling recirculating flows. It transpires that the introduction of swirl has a profound effect on stability. In particular, the flows produced by magnetic relaxation are no longer stable. Indeed, we show that all swirling recirculating Euler flows are potentially unstable to the extent that they fail to satisfy Arnol’d's stability criterion. This is, perhaps, not surprising, as all swirling recirculating flows include regions where the angular momentum decreases with radius and we would intuitively expect such flows to be prone to a centrifugal instability. The paper concludes with a discussion of marginally unstable modes in swirling flows. In particular, we examine the extent to which Rayleigh's original ideas on stability may be generalized, through the use of the Routhian, to include flows with a non-zero recirculation.

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Liu, Yu, and Shibao Wu. "Proposed Scheme for Ultra-Flat Optical Frequency Comb Generation Based on Dual-Drive Mach–Zehnder Modulators and Bidirectional Recirculating Frequency Shifting in Single Loop." Photonics 9, no. 8 (July 24, 2022): 514. http://dx.doi.org/10.3390/photonics9080514.

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Recirculating frequency shifting has attracted much attention for its advantages in the generation of the flexible and high-quality optical frequency comb. A new scheme of ultra-flat optical frequency comb generation system based on single-loop bidirectional recirculating frequency shift is proposed and studied in this paper. The generation system employs two pairs of dual-drive Mach–Zehnder modulators and several polarization devices. Compared with the method of single-loop unidirectional recirculation frequency shift, under the same cycles, the number of comb lines generated by the proposed method is doubled, and the generated optical frequency combs have less noise accumulation and better flatness. The theoretical model is established, and the proposed scheme is verified by software simulation. A 111-line optical frequency comb with the spacing of 12.5 GHz, the flatness of 0.76 dB, and the optical signal-to-noise ratio of 27.39 dB was obtained by adopting the proposed scheme.

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Layek, G. C., C. Midya, and S. Mukhopadhyay. "Effects of Suction and Blowing on Flow Separation in a Symmetric Sudden Expanded Channel." Nonlinear Analysis: Modelling and Control 13, no. 4 (October 20, 2008): 451–65. http://dx.doi.org/10.15388/na.2008.13.4.14551.

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A numerical simulation has been carried out to study the laminar flow in a symmetric sudden expanded channel subjected to a uniform blowing/suction speed placed at the lower and upper porous step walls. The governing equations for viscous flow have been solved using finite-difference techniques in pressure-velocity formulation. The results obtained here have been compared with the available experimental and numerical results of similar problems. It is noted that the recirculating region formed near the step walls diminishes in its length for increasing values of blowing speed applied at the porous step walls. For a suitable blowing speed, the recirculation zone disappears completely. The critical Reynolds number for the flow bifurcation (i.e. flow asymmetry) is obtained and it increases with the increase of the blowing speed. The critical Reynolds number for symmetry breaking of the flow decreases with the increasing values of suction speeds. The primary and the secondary recirculating regions formed near the channel walls are controlled using blowing.

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Ljung, Anna-Lena, L. Robin Andersson, Anders G. Andersson, T. Staffan Lundström, and Mats Eriksson. "Modelling the Evaporation Rate in an Impingement Jet Dryer with Multiple Nozzles." International Journal of Chemical Engineering 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/5784627.

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Impinging jets are often used in industry to dry, cool, or heat items. In this work, a two-dimensional Computational Fluid Dynamics model is created to model an impingement jet dryer with a total of 9 pairs of nozzles that dries sheets of metal. Different methods to model the evaporation rate are studied, as well as the influence of recirculating the outlet air. For the studied conditions, the simulations show that the difference in evaporation rate between single- and two-component treatment of moist air is only around 5%, hence indicating that drying can be predicted with a simplified model where vapor is included as a nonreacting scalar. Furthermore, the humidity of the inlet air, as determined from the degree of recirculating outlet air, has a strong effect on the water evaporation rate. Results show that the metal sheet is dry at the exit if 85% of the air is recirculated, while approximately only 60% of the water has evaporated at a recirculation of 92,5%.

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Davidson, P. A. "The interaction between swirling and recirculating velocity components in unsteady, inviscid flow." Journal of Fluid Mechanics 209 (December 1989): 35–55. http://dx.doi.org/10.1017/s0022112089003022.

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In this paper we consider the transient evolution of a swirling, recirculating flow in a truncated cylinder. In particular, we consider an initial time period during which the evolution of the flow is controlled by inertia. Such flows exhibit a mutual interaction between the swirl and the poloidal recirculation, whereby any axial gradient in swirl alters the recirculation, which, in turn, redistributes the swirl. This interaction may be visualized as a flexing of the poloidal vortex lines, the best known example of which is the inertial wave. Physical arguments and numerical experiments suggest that, typically, a strong, oscillatory recirculation will develop. We examine the exchange of energy between the swirl and recirculation, and show that the direction of transfer depends on the relative signs of ψ and ηuθ/ηz. In addition, there is a limit to the amount of energy that may be exchanged, since conservation of angular momentum imposes a lower bound on the kinetic energy of the swirl. The characteristic reversal time for the recirculation is estimated by considering the history of fluid particles on the endwalls. Its magnitude depends on the relative strengths of the swirl and recirculation. When the recirculation is large, the reversal time exceeds the turn-over time for a poloidal eddy and, consequently, the vortex lines accumulate at the stagnation points on the endwalls. This leads to accelerated local diffusion on the axis. An elementary one-parameter model is proposed for these nonlinear oscillations. In the limit of very weak recirculation, this model is consistent with the exact solution for inertial waves, while for strong recirculation, it confirms that the reversal time is greater than the turn-over time, and that the vortex lines accumulate on the axis.

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Lindequist, S., J. E. Madsen, I. Christensen, and B. Nielsen. "Film processing and the environment." Acta Radiologica 39, no. 3 (May 1998): 332–36. http://dx.doi.org/10.1080/02841859809172206.

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Purpose: X-ray film processing is associated with pollution from photo chemicals and from the water used to rinse the film. We tested a new processing system that was aimed at reducing both environmental pollution and costs through the use of solid photo chemicals and recirculation of the rinsing water Material and Methods: Before and after the installation of new mixers for the solid chemicals and a system for recirculating the rinsing water, we measured: water consumption, processor function quality, image quality, archivability, and the waste-silver content in the rinsing water Results: After the installation of a simple system for recirculating the rinsing water, there was an 88% reduction in water and film consumption as shown in the amount of water/m2film that was used. At the same time, the release of silver-contaminated rinsing water directly into the sewers was stopped. Image quality remained unchanged. Archivability was assessed at more than 100 years. The solid photo chemicals and specially designed mixers proved efficient and provided a stable image quality of high standard. It was thus possible to reduce the risk of pollution from the transportation, storage and handling of liquid chemicals Conclusion: A simple recirculation system for the rinsing water would significantly reduce water consumption and eliminate contamination of the environment by silver. The on-site preparation of photo chemicals proved viable and reduced the costs of film processing

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Benestad, Haakon Breien, Jens-Gustav Iversen, and Bent Rolstad. "Immunoblast Formation by Recirculating and Non-Recirculating Rat Lymphocytes Cultured in Diffusion Chambers." Scandinavian Journal of Haematology 8, no. 1 (April 24, 2009): 32–43. http://dx.doi.org/10.1111/j.1600-0609.1971.tb02669.x.

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Mossaz, Stéphane, Pascal Jay, and Albert Magnin. "Non-recirculating and recirculating inertial flows of a viscoplastic fluid around a cylinder." Journal of Non-Newtonian Fluid Mechanics 177-178 (June 2012): 64–75. http://dx.doi.org/10.1016/j.jnnfm.2012.04.008.

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43

Bridges, C. R. "‘Recirculating cardiac delivery’ method of gene delivery should be called ‘non-recirculating’ method." Gene Therapy 16, no. 7 (April 2, 2009): 939–40. http://dx.doi.org/10.1038/gt.2009.35.

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44

Barber, Kevin M., Aaron Pinero, and George A. Truskey. "Effects of recirculating flow on U-937 cell adhesion to human umbilical vein endothelial cells." American Journal of Physiology-Heart and Circulatory Physiology 275, no. 2 (August 1, 1998): H591—H599. http://dx.doi.org/10.1152/ajpheart.1998.275.2.h591.

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We used a sudden-expansion flow chamber to examine U-937 cell adhesion to unactivated and tumor necrosis factor (TNF)-α-activated human umbilical vein endothelial cells (HUVEC) in recirculating flow. For both unactivated and TNF-α-activated HUVEC, U-937 cells exhibited transient arrests within ∼150 μm of flow reattachment. Few arrests occurred directly at the reattachment site. U-937 cell rolling was not observed. At all other locations within the recirculation zone, U-937 cells did not exhibit transient arrests or rolling. TNF-α activation increased the frequency of U-937 cell arrests near reattachment but did not change the median arrest duration. Numerically simulated cell trajectories failed to predict attachment near the reattachment point. Deviations between experiment and theory may result from the nonspherical shape and deformability of U-937 cells. These results demonstrate that U-937 cell transient arrests occur preferentially in the vicinity of the reattachment point in recirculating flow. Possible mechanisms for adhesion include low shear stress, curved streamlines, fluid velocity components normal to the endothelium, and formation of larger contact areas.

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45

Wang, Wei, Wuli Chu, and Haoguang Zhang. "Mechanism study of performance enhancement in a subsonic axial flow compressor with recirculating casing treatment." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 232, no. 4 (January 11, 2017): 680–93. http://dx.doi.org/10.1177/0954410016687140.

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The improvements in both compressor efficiency and stability have been observed in a subsonic axial flow compressor with recirculating casing treatment. The study aims to understand the underlying flow mechanisms of the beneficial effect on the compressor efficiency of recirculating casing treatment. The recirculating casing treatment was investigated experimentally and numerically. In the experiment, static pressure fluctuations over the rotor tip were measured with fast-response pressure transducers. Whole-passage time-accurate simulations were also implemented to help in understanding the flow details. The unsteadiness of double-leakage flow and its effect on the loss generated at the rotor tip were discussed in detail for the solid casing. The effect of recirculating casing treatment on the double-leakage flow related loss was subsequently investigated. The results indicate that the double leakage flow is a main loss source in the rotor tip region. The double-leakage flow is completely unsteady, which induces a cyclical fluctuation of the amount of loss generated in the rotor tip region for the solid casing. With the recirculating casing treatment installed, the high-energy jet created in recirculating loops changes the unsteady characteristics of double-leakage flow by getting it diffused over the rotor tip gap along the chordwise direction, which results in the loss fluctuation that is dominated by the high-energy jet rather than the unsteadiness of double-leakage flow. The double-leakage flow is also pushed downstream by the jet and the amount is reduced when it passes through the recirculating loops. The effect of recirculating casing treatment on the double-leakage flow is primarily responsible for the improvement in the compressor efficiency.

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46

Andrade, William N., Miles G. Johnston, and John B. Hay. "The Relationship of Blood Lymphocytes to the Recirculating Lymphocyte Pool." Blood 91, no. 5 (March 1, 1998): 1653–61. http://dx.doi.org/10.1182/blood.v91.5.1653.

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Abstract Lymphocyte recirculation facilitates the detection and elimination of pathogens and the dissemination of immunologic memory. It is generally assumed that all small lymphocytes in the blood are actively recirculating, yet there is little quantitative data directly comparing the migration of this population with actively recirculating, lymph-derived lymphocytes. In this study blood lymphocytes were labeled with fluorescein isothiocyanate (FITC), and lymph lymphocytes were labeled with CM-DiI, reinfused intravenously, and monitored in blood and lymph. After equilibration the concentration of blood lymphocytes was several times higher in blood than in lymph, whereas lymph lymphocytes displayed the opposite behavior. This suggested that blood lymphocytes did not recirculate as efficiently as lymph lymphocytes, so we examined the following blood lymphocyte subsets in greater detail: B cells, CD4+, CD8+, and γδ T cells. Within 4 hours postinjection the percentage of FITC+CD8+ and CD4+ lymphocytes fell in the blood and remained significantly lower than the injected sample. In contrast, the concentration of FITC+ γδ T cells did not change, and the percentage of FITC+ B cells increased. These data suggest that subpopulations of B and perhaps γδ T lymphocytes in the blood do not recirculate efficiently through lymph nodes.

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47

Andrade, William N., Miles G. Johnston, and John B. Hay. "The Relationship of Blood Lymphocytes to the Recirculating Lymphocyte Pool." Blood 91, no. 5 (March 1, 1998): 1653–61. http://dx.doi.org/10.1182/blood.v91.5.1653.1653_1653_1661.

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Lymphocyte recirculation facilitates the detection and elimination of pathogens and the dissemination of immunologic memory. It is generally assumed that all small lymphocytes in the blood are actively recirculating, yet there is little quantitative data directly comparing the migration of this population with actively recirculating, lymph-derived lymphocytes. In this study blood lymphocytes were labeled with fluorescein isothiocyanate (FITC), and lymph lymphocytes were labeled with CM-DiI, reinfused intravenously, and monitored in blood and lymph. After equilibration the concentration of blood lymphocytes was several times higher in blood than in lymph, whereas lymph lymphocytes displayed the opposite behavior. This suggested that blood lymphocytes did not recirculate as efficiently as lymph lymphocytes, so we examined the following blood lymphocyte subsets in greater detail: B cells, CD4+, CD8+, and γδ T cells. Within 4 hours postinjection the percentage of FITC+CD8+ and CD4+ lymphocytes fell in the blood and remained significantly lower than the injected sample. In contrast, the concentration of FITC+ γδ T cells did not change, and the percentage of FITC+ B cells increased. These data suggest that subpopulations of B and perhaps γδ T lymphocytes in the blood do not recirculate efficiently through lymph nodes.

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48

Chachoua, Abderrahmane, Mohamed Kamal Hamidou, and Mohammed Hamel. "Performance investigation of a volute porous tongue of a turbocharger turbine." Engineering review 40, no. 1 (January 27, 2020): 59–66. http://dx.doi.org/10.30765/er.40.1.08.

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The design for better performance of the spiral housing volute used commonly in radial and mixed inflow gas turbines is of prime importance as it affects the machine stage at both design and off design conditions. The tongue of the scroll divides the flow into two streams, and represents a severe source of disturbances, in terms of thermodynamic parameter uniformity, maximum kinetic energy, the right angle of attack to the rotor and minimum losses. Besides, the volute suffers an undesirable effect due to the recirculating mass flow rate in near bottom vicinity of the tongue. The present project is an attempt to design a tongue fitted with cylindrical holes traversing normal to the stream wise direction, where on account of the large pressure difference between the top and the bottom sides of the tongue will force the recirculating flow to go through the rotor inlet. This possibility with its limitations has not yet been explored. A numerical simulation is performed which might provide our suitable objectives. To achieve this goal the ANSYS code is used to build the geometry, generate the mesh, and to simulate the flow by solving numerically the averaged Navier Stokes equations. Apparently, the numerical results show evidence of favorable impact in using porous tongue. The realization of a contact between the main and recirculation flow by drilled holes on the tongue surface leads to a flow field uniformity, a reduction in the magnitude of the loss coefficient, and a 20 % reduction in the recirculating mass flow rate.

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Choudhuri, P. Ghosh, and D. D. Knight. "Effects of compressibility, pitch rate, and Reynolds number on unsteady incipient leading-edge boundary layer separation over a pitching airfoil." Journal of Fluid Mechanics 308 (February 10, 1996): 195–217. http://dx.doi.org/10.1017/s0022112096001450.

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The effects of compressibility, pitch rate and Reynolds number on the initial stages of two-dimensional unsteady separation of laminar subsonic flow over a pitching NACA-0012 airfoil have been studied numerically. The approach involves the simulation of the flow by solving the two-dimensional unsteady compressible laminar Navier-Stokes equations employing the implicit approximate-factorization algorithm of Beam & Warming and a boundary-fitted C-grid. The algorithm has been extensively validated through comparison with analytical and previous numerical results. The computations display several important trends for the ‘birth’ of the primary recirculating region which is a principal precursor to leading-edge separation. Increasing the non-dimensional pitch rate from 0.05 to 0.2 at a fixed Reynolds number and Mach number delays the formation of the primary recirculating region. The primary recirculating region also forms closer to the leading edge. Increasing the Mach number from 0.2 to 0.5 at a fixed Reynolds number and pitch rate causes a delay in the formation of the primary recirculating region and also leads to its formation farther from the airfoil top surface. The length scale associated with the recirculating regions increases as well. Increasing the Reynolds number from 104 to 105 at a fixed Mach number and pitch rate hastens the appearance of the primary recirculating region. A shock appears on the top surface at a Reynolds number of 105 along with the simultaneous formation of multiple recirculating regions near the leading edge.

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Peralbo, A., F. Flores, and J. López-Medina. "RECIRCULATING NUTRIENT SOLUTION IN STRAWBERRY." Acta Horticulturae, no. 697 (December 2005): 101–6. http://dx.doi.org/10.17660/actahortic.2005.697.11.

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Journal articles on the topic 'Recirculating'

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