Journal articles: 'Volumetric flow rate'

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Hoyt, Kenneth, Felix A. Hester, Randall L. Bell, Mark E. Lockhart, and Michelle L. Robbin. "Accuracy of Volumetric Flow Rate Measurements." Journal of Ultrasound in Medicine 28, no. 11 (November 2009): 1511–18. http://dx.doi.org/10.7863/jum.2009.28.11.1511.

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Hedlund, H. "Calculating Linear Flow Velocity from Volumetric Flow Rate." Cold Spring Harbor Protocols 2010, no. 2 (February 1, 2010): pdb.ip78. http://dx.doi.org/10.1101/pdb.ip78.

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Calafiore, P. a. u. l., and William Stewart. "Doppler Echocardiographic Quantitation of Volumetric Flow Rate." Cardiology Clinics 8, no. 2 (May 1990): 191–202. http://dx.doi.org/10.1016/s0733-8651(18)30362-x.

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Kovalčíková, KristÍna, Martin Slavík, Katarína Bachratá, Hynek Bachratý, and Alžbeta Bohiniková. "Volumetric flow rate in simulations of microfluidic devices." EPJ Web of Conferences 180 (2018): 02046. http://dx.doi.org/10.1051/epjconf/201818002046.

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In this work, we examine the volumetric flow rate of microfluidic devices. The volumetric flow rate is a parameter which is necessary to correctly set up a simulation of a real device and to check the conformity of a simulation and a laboratory experiments [1]. Instead of defining the volumetric rate at the beginning as a simulation parameter, a parameter of external force is set. The proposed hypothesis is that for a fixed set of other parameters (topology, viscosity of the liquid, …) the volumetric flow rate is linearly dependent on external force in typical ranges of fluid velocity used in our simulations. To confirm this linearity hypothesis and to find numerical limits of this approach, we test several values of the external force parameter. The tests are designed for three different topologies of simulation box and for various haematocrits. The topologies of the microfluidic devices are inspired by existing laboratory experiments [3 - 6]. The linear relationship between the external force and the volumetric flow rate is verified in orders of magnitudes similar to the values obtained from laboratory experiments.

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Elgmati, A. R., R. E. Flori, and C. S. Kabir. "Analyzing variable-rate flow in volumetric oil reservoirs." Journal of Petroleum Science and Engineering 135 (November 2015): 268–79. http://dx.doi.org/10.1016/j.petrol.2015.08.017.

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Chern, Ming-Jyh, and Chih-Cheng Wang. "Control of Volumetric Flow-Rate of Ball Valve Using V-Port." Journal of Fluids Engineering 126, no. 3 (May 1, 2004): 471–81. http://dx.doi.org/10.1115/1.1760536.

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The control of volume flow rate in a ball valve is very important when a ball valve is utilized in a piping system. It is difficult to linearly control the flow rate in a ball valve without external devices. V-ports are employed to achieve this purpose. In order to investigate the effects of V-port on the volume flow rate and flow features, 3-D numerical simulations and experiments were conducted to observe the flow patterns and to measure performance coefficients when V-ports with various angles were used in a piping system. Three V-ports with angles 30 deg, 60 deg, and 90 deg were studied. It was found that V-ports with angles 30 deg and 60 deg make the flow rate proportional to the valve opening. However, V-ports increase the pressure loss between the inlet and the exit of a ball valve. In addition, V-ports with a small angle such as 30 deg increase the possibility of cavitation compared with flows without V-ports.

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Mulyono, Panut, I. Made Bendiyasa, Dita Budi Wibawa, and Suryo Birowo. "Sistem penyimpanan energi panas kontak langsung menggunakan larutan Na₂HPO₄•12H₂O." Jurnal Teknik Kimia Indonesia 4, no. 3 (October 9, 2018): 270. http://dx.doi.org/10.5614/jtki.2005.4.3.2.

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The volumetric coefficient of heat transfer and the energy storage capacity in a direct contact thermal energy storage system using Na2HPO4.12H2O solution as thermal energy storage medium have been investigated. Hot kerosene was used as a heal transfer fluid. The experiments were carried out by bubbling hot kerosene from the bottom of a column containing Na2HPO4.12H2O solution. The column used in this experiment was made from glass of 3 mm in thickness with an inside diameter of 7 cm and a height of 100 cm. The effects of kerosene flow rate and kerosene bubble diameter on the volumetric coefficient of heat transfer and the storing rate of energy were studied. It was found that the volumetric coefficient of heat transfer was strongly affected by the flow rate of the kerosene and that the effect of the kerosene flow rate on the storing rate of energy was relative v high, while that of the effect of the bubble diameter was neglectable.Keywords: Direct Contact, Thermal Energy Storage System, Na2HPO4.12H2O Solution AbstrakPenelitian ini mempelajari sistem penyimpanan energi panas kontak langsung menggunakan larutan Na2HPO4.12H2O sebagai media penyimpan energi. Kerasin panas digunakan sebagai fluida alir sumber energi panas. Masalah yang dipelajari pada penelitian ini adalah nilai koefisien perpindahan panas volumetris dan kapasitas penyimpanan panasnya. Percobaan dilakukan dengan menggelembungkan kerasin panas dari dasar kolom yang berisi larutan Na2HPO4.12H2O. Kolom yang digunakan dibuat dari gelas dengan ketebalan 3 mm, mempunyai diameter dalam 7 cm, dan tinggi kolomnya adalah 100 cm. Parameter yang dipelajari dalam penelitian ini adalah pengaruh kecepatan volumetris kerosin dan pengaruh diameter gelembung kerosin terhadap nilai koefisien perpindahan panas volumetris dan terhadap kecepatan penyimpanan panasnya. Hasil penelitian menunjukkan bahwa nilai koejisien perpindahan panas volumetris sangat dipengaruhi oleh kecepatan volumetris kerosin sehingga kecepatan penyimpanan panasnya juga sangat dipengaruhi oleh kecepatan volumetris kerosin. Pengaruh ukuran diameter gelembung terhadap nilai koefisien perpindahan panas volumetris dan terhadap kecepatan penyimpanan panasnya sangat kecil sehingga dapat diabaikan.Kata Kunci: Sistem Penyimpanan Energi Panas, Kontak Langsung, Larutan Na2HPO4.12H2O

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Treaftis, Harry N., Thomas F. Tomb, and Andrew J. Gero. "Effect of Altitude on the Volumetric Flow Rate of Constant Flow Pumps." Applied Industrial Hygiene 1, no. 1 (April 1986): 54–58. http://dx.doi.org/10.1080/08828032.1986.10390444.

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Chesnokov, V. I. "Improving the estimation of methodological errors in reproducing the volumetric air flow rate by reference critical nozzle." Metrologiya, no. 1 (May 31, 2021): 4–30. http://dx.doi.org/10.32446/0132-4713.2021-1-4-30.

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In the development of the previously obtained results a more accurate estimate of the methodological error in reproducing the volumetric air flow rate by reference critical nozzle is given, associated with the choice of the gas flow model and due to taking into account the initial kinetic energy of the flow at the nozzle inlet. Based on improved flow model an analytical evaluation of the methodological error in reproducing the volumetric air flow rate by reference critical nozzle, which is due to a change in the humidity of the working air, has been carried out. It is shown that the methodological error in reproducing the volumetric air flow rate by reference critical nozzle, associated with a change in the air humidity, as well as the analogies methodical error caused by the existence of the initial kinetic energy of the flow, must be taken part in accuracy characteristics at the real operating conditions of the standard volumetric air flow rate using critical nozzles.

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Shenoy, Aroon. "Unifying Asphalt Rheological Data Using the Material's Volumetric-Flow Rate." Journal of Materials in Civil Engineering 13, no. 4 (August 2001): 260–73. http://dx.doi.org/10.1061/(asce)0899-1561(2001)13:4(260).

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11

Heitmann, F., M. Juling, and J. Steinbock. "Performance of the LDA Volumetric Flow Rate Standard Under Severely Disturbed Flow Conditions." Flow Measurement and Instrumentation 74 (August 2020): 101756. http://dx.doi.org/10.1016/j.flowmeasinst.2020.101756.

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12

Bopp, S., F. Durst, M. Teufel, and H. Weber. "Volumetric flow rate measurements in oscillating pipe flows with a laser-Doppler sensor." Measurement Science and Technology 1, no. 9 (September 1, 1990): 917–23. http://dx.doi.org/10.1088/0957-0233/1/9/014.

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13

Bansal, Rajeev, and Samir Das. "Analytical Solution for Transient Hydraulic Head, Flow Rate and Volumetric Exchange in an Aquifer Under Recharge Condition." Journal of Hydrology and Hydromechanics 57, no. 2 (June 1, 2009): 113–20. http://dx.doi.org/10.2478/v10098-009-0010-4.

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Analytical Solution for Transient Hydraulic Head, Flow Rate and Volumetric Exchange in an Aquifer Under Recharge ConditionThis paper presents closed form solution for unsteady flow equation corresponding to the transient hydraulic head, flow rate and volumetric exchange of a confined aquifer which is in contact with a constant piezometric head at one end and a stream whose water level is rising at a constant rate at the other end. The aquifer is also subjected to receive constant inflow due to rain infiltration. The unsteady groundwater flow equation is solved using Laplace transform to get analytical expressions for the transient hydraulic head and flow rate at the left and right interfaces and the net volumetric exchange of water at the aquifer-stream interface. The analytical results presented here show the effect of recharge due to rain infiltration on the net volumetric exchange and reveal the conditions for which net inflow in the aquifer could be positive, negative or zero. The results obtained have the capability to determine transient hydraulic head for two extreme scenarios: (i) very slow rise and (ii) very fast rise in the stream water. Analytical result show that the net volumetric exchange could be positive, zero or negative depending on the surface infiltration and stream water rise rate.

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Hamakiotes, Costas C., and Stanley A. Berger. "Periodic flows through curved tubes: the effect of the frequency parameter." Journal of Fluid Mechanics 210 (January 1990): 353–70. http://dx.doi.org/10.1017/s002211209000132x.

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In a previous paper we reported on the effect of Dean number, κm, on the fully developed region of periodic flows through curved tubes. In this paper we again consider a sinusoldally varying volumetric flow rate in a curved pipe of arbitrary curvature ratio, δ, and investigate the effect of frequency parameter α, and Reynolds number Rem on the flow. Specifically, we report on the flow-field development for the range 7.5 [les ] α [les ] 25, and 50 [les ] Rem [les ] 450. The results, obtained by numerical integration of the full Navier–Stokes equations, reveal a number of characteristics of the flow previously unreported. For low values of Rem the secondary flow consists of a single vortex (Dean-type motion) in the half-cross-section at all times and for all values of α studied. For higher Rem we observe inward ‘centrifuging’ (Lyne-type motion) at the centre. This motion always occurs during the accelerating period of the volumetric flow rate. It appears at lower α for higher Rem and, for the given Rem at which it appears, it occurs at earlier times in the cycle for lower a. A striking feature is observed for α = 15 for the range 315 [les ] Rem [les ] 400: period tripling. The flow field varies periodically with time for the duration of three volumetric-flow-rate cycles then repeats for the subsequent three cycles, and so on. The computed axial pressure gradient also varies periodically with time but with the same period as the volumetric flow rate.

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Minemura, K., K. Egashira, K. Ihara, H. Furuta, and K. Yamamoto. "Simultaneous Measuring Method for Both Volumetric Flow Rates of Air-Water Mixture Using a Turbine Flowmeter." Journal of Energy Resources Technology 118, no. 1 (March 1, 1996): 29–35. http://dx.doi.org/10.1115/1.2792689.

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A turbine flowmeter is employed in this study in connection with offshore oil field development, in order to measure simultaneously both the volumetric flow rates of air-water two-phase mixture. Though a conventional turbine flowmeter is generally used to measure the single-phase volumetric flow rate by obtaining the rotational rotor speed, the method proposed additionally reads the pressure drop across the meter. After the pressure drop and rotor speed measured are correlated as functions of the volumetric flow ratio of the air to the whole fluid and the total volumetric flow rate, both the flow rates are iteratively evaluated with the functions on the premise that the liquid density is known. The evaluated flow rates are confirmed to have adequate accuracy, and thus the applicability of the method to oil fields.

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16

Greeff, G. P. "Material Flow Rate Estimation in Material Extrusion Additive Manufacturing." NCSL International measure 13, no. 1 (2021): 46–56. http://dx.doi.org/10.51843/measure.13.1.5.

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The additive manufacturing of products promises exciting possibilities. Measurement methodologies, which measure an in-process dataset of these products and interpret the results, are essential. However, before developing such a level of quality assurance several in-process measurands must be realized. One of these is the material flow rate, or rate of adding material during the additive manufacturing process. Yet, measuring this rate directly in material extrusion additive manufacturing presents challenges. This work presents two indirect methods to estimate the volumetric flow rate at the liquefier exit in material extrusion, specifically in Fused Deposition Modeling or Fused Filament Fabrication. The methods are cost effective and may be applied in future sensor integration. The first method is an optical filament feed rate and width measurement and the second is based on the liquefier pressure. Both are used to indirectly estimate the volumetric flow rate. The work also includes a description of linking the G-code command to the final print result, which may be used to create a per extrusion command model of the part.

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Akkarawatkhoosith, Nattee, Wannarak Nopcharoenkul, Amaraporn Kaewchada, and Attasak Jaree. "Mass Transfer Correlation and Optimization of Carbon Dioxide Capture in a Microchannel Contactor: A Case of CO2-Rich Gas." Energies 13, no. 20 (October 19, 2020): 5465. http://dx.doi.org/10.3390/en13205465.

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This work focused on the application of a microchannel contactor for CO2 capture using water as absorbent, especially for the application of CO2-rich gas. The influence of operating conditions (temperature, volumetric flow rate of gas and liquid, and CO2 concentration) on the absorption efficiency and the overall liquid-side volumetric mass transfer coefficient was presented in terms of the main effects and interactions based on the factorial design of experiments. It was found that 70.9% of CO2 capture was achieved under the operating conditions as follows; temperature of 50 °C, CO2 inlet fraction of 53.7%, total gas volumetric flow rate of 150 mL min−1, and adsorbent volumetric flow rate of 1 mL min−1. Outstanding performance of CO2 capture was demonstrated with the overall liquid-side volumetric mass transfer coefficient of 0.26 s−1. Further enhancing the system by using 2.2 M of monoethanolamine in water (1:1 molar ratio of MEA-to-CO2) boosted the absorption efficiency up to 88%.

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Wiroonritichai, Chanchai, and Pollakrit Kritmaitree. "Experimental Study of Wind Driven Scroll Pump." Applied Mechanics and Materials 565 (June 2014): 147–51. http://dx.doi.org/10.4028/www.scientific.net/amm.565.147.

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This paper describes the feasibility study of wind driven scroll pump for wind energy application using in Thailand to design, fabricate and test. The testing set was adapted by the Japanese Industrial Standards (JIS B 8301) to define the relationship of pressure and flow rate curve (H-Q Curves), the relatioship of flow rate and pump speed , and the volumetric flow rate. The results presented the pressure and flow rate which showed the inverse variation in linear equations. The speed of the pump and flow rate were direct variation in linear equations. The maximum flow rate was 20.23 liters/minute in the speed of 714 RPM which fully opened valve. The average of volumetric efficiency was 89.55%.

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Zhao, Peng, Zhongyuan Yuan, Yanping Yuan, Nanyang Yu, and Tao Yu. "A Study on Ceiling Temperature Distribution and Critical Exhaust Volumetric Flow Rate in a Long-Distance Subway Tunnel Fire with a Two-Point Extraction Ventilation System." Energies 12, no. 8 (April 12, 2019): 1411. http://dx.doi.org/10.3390/en12081411.

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Smoke control is a crucial issue in a long-distance subway tunnel fire, and a two-point extraction ventilation system is an effective way to solve this problem, due to the characteristics of controlling the smoke in a limited area and removing high-temperature and toxic smoke in time. In this study, the ceiling temperature distribution and the critical exhaust volumetric flow rate to control the smoke in the zone between two extraction vents were investigated in a long-distance subway tunnel fire with a two-point extraction ventilation system. Experiments were carried out in a 1/20 reduced-scale tunnel model based on Froude modeling. Factors, including the heat release rate (HRR), the extraction vent length, the internal distance between two extraction vents and exhaust volumetric flow rate, were studied. Smoke temperature below the ceiling, exhaust volumetric flow rate and smoke spreading configurations were measured. The ceiling temperature distribution was analyzed. Meanwhile, an empirical equation was developed to predict the critical exhaust volumetric flow rate based on the one-dimensional theory, experimental phenomenon and the analysis of forces acting at the smoke underneath the extraction vent. The coefficients in the empirical equation were determined by experimental data. Compared with the experimental results, the developed empirical equation can predict the critical exhaust volumetric flow rate well. Research outcomes in this study will be beneficial to the design and application of two-point extraction ventilation system for a long-distance subway tunnel fire.

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Tomida, Tahei, Tatsuya Okazaki, Masahiro Kubo, and Noboru Suekuni. "Volumetric rate of light absorption in gas-liquid two-phase flow." Industrial & Engineering Chemistry Process Design and Development 25, no. 1 (January 1986): 203–7. http://dx.doi.org/10.1021/i200032a032.

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Schlesser, J. E., W. H. Stroup, and J. A. McKinstry. "Volumetric Flow Rate Comparisons for Water and Product on Pasteurization Systems." Journal of Dairy Science 77, no. 4 (April 1994): 950–57. http://dx.doi.org/10.3168/jds.s0022-0302(94)77031-4.

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Vajda, Péter, Joseph J. Stankovich, and Georges Guiochon. "Determination of the average volumetric flow rate in supercritical fluid chromatography." Journal of Chromatography A 1339 (April 2014): 168–73. http://dx.doi.org/10.1016/j.chroma.2014.02.078.

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Wang, Yang, Yimin Xia, Xuemeng Xiao, Huiwang Xu, Peng Chen, and Guiying Zeng. "Ballast Flow Characteristics of Discharging Pipeline in Shield Slurry System." Applied Sciences 9, no. 24 (December 10, 2019): 5402. http://dx.doi.org/10.3390/app9245402.

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We adopted two-way coupling of discrete and finite elements to examine the non-spherical ballast flow characteristics in a slurry pipe system during a shield project. In the study, we considered the slurry rheological property and the flake shape of the ballast. A ballast size between 17 and 32 mm under different slurry flow rates and ballast volumetric concentration conditions was investigated for determining the law through which the mass flow rate, detained mass percentage, and ballast distribution state are influenced. The results indicate that increasing slurry flow rate and the ballast volumetric concentration increase the mass flow rate; the influence of the latter is stronger. Increases in both in the slurry flow rate and the ballast volumetric concentration can reduce the detained mass percentage in the slurry discharging pipeline, whereas increasing the ballast size has the opposite effect. The increase in both the slurry flow rate and the ballast size changes the ballast motion state. Experiments verified the numerical lifting model of the ballast in the vertical pipeline. The measurements of the actual pipeline wall thickness verified that the simulation results regarding the ballast distribution were accurate.

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Azizan, Amizon, and Nornizar Anuar. "Simulating Trambouze reaction for a series reactor." Malaysian Journal of Chemical Engineering and Technology (MJCET) 3, no. 1 (November 30, 2020): 1. http://dx.doi.org/10.24191/mjcet.v3i1.10930.

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Simulating the existing data on Trambouze reaction is compiled in this article. The objective of the work is to present the change of volumetric flow rate and the inlet concentration of key reactant A in a series continuous stirred tank reactor-plug flow reactor (CSTR-PFR) configurations. The volumetric flow rate does not affect selectivity and conversion for a constant volumetric flow rate operating condition, entering CSTR and PFR, at a specific concentration of reactant. The CSTR-PFR series reactor configuration is proposed for the aim of maximizing the selectivity of the desired product B in comparison to the undesired products X and Y. CSTR as the first reactor is capable to achieve the maximum conversion at the highest selectivity of A. PFR is then proposed after CSTR in a configuration of CSTR-PFR, to allow higher conversion value to be achieved for the resulted outlet stream conditions coming out of the first reactor, CSTR. Both reactors commonly encounter a decrease in the initial concentration of A and an increase to the formation of other products. The CSTR entering volumetric flow rate influence the volume sizes needed in achieving the maximum selectivity and conversion

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Wright, John D., Michael R. Moldover, Aaron N. Johnson, and Akisato Mizuno. "Volumetric Gas Flow Standard With Uncertainty of 0.02% to 0.05%." Journal of Fluids Engineering 125, no. 6 (November 1, 2003): 1058–66. http://dx.doi.org/10.1115/1.1624428.

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A new pressure, volume, temperature, and time (PVTt) primary gas flow standard for calibrating flowmeters has an expanded uncertainty k=2 of between 0.02% and 0.05%. The standard diverts a steady flow into a collection tank of known volume during a measured time interval. The standard spans the flow range of 1 slm1 to 2000 slm using two collection tanks (34 L and 677 L) and two flow diversion systems. We describe the novel features of the standard and analyze its uncertainty. The thermostatted collection tank allows determination of the average gas temperature to 7 mK (0.0023%) within an equilibration time of 20 min. We developed a mass cancellation procedure that reduced the uncertainty contributions from the inventory volume to 0.017% at the highest flow rate. Flows were independently measured throughout the overlapping flow range of the two systems and they agreed within 0.015 %. The larger collection system was evaluated at high flows by comparing single and double diversions; the maximum difference was 0.0075%.

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Ciufo, David J., Michael R. Anderson, and Judith F. Baumhauer. "Impact of Knee Scooter Flexion Position on Venous Flow Rate." Foot & Ankle International 40, no. 1 (September 3, 2018): 80–84. http://dx.doi.org/10.1177/1071100718794966.

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Background: The knee scooter is a commonly used mobility device in the setting of unilateral below-knee immobilization. The bent-knee posture has been shown to decrease venous flow in a seated position, but the knee scooter differs as the patient is weightbearing through the affected extremity. Our goal was to investigate the effects of knee scooter positioning on popliteal venous flow. Methods: Duplex ultrasonography was performed to obtain venous diameter and flow velocity of the popliteal vein on healthy subjects over the age of 18 without immobilization. Measurements were performed on the left knee of each subject while standing and with the same knee flexed on the knee scooter, by 2 physicians trained in ultrasound techniques. Mean velocity, peak velocity, vessel diameter, and volumetric flow rate were calculated and t tests were performed for each variable. A power analysis was performed, determining that 9 subjects would provide 80% power with an alpha of 0.05. A total of 13 subjects participated in the study. Mean age was 33 (range 20-56) years, with 6 females and 7 males. Results: Measurements of subjects while standing and on the knee scooter demonstrated a significant decrease in mean velocity (6.5 vs 3.2 cm/s, P < .01) and volumetric flow rate (227.8 vs 106.2 mL/min, P < .01) while subjects were using the scooter. Vessel diameter (0.82 vs 0.78 cm, P = .15) and peak velocities (19.8 vs 14.7 cm/s, P = .19) were not significantly different between standing and kneeling positions. Conclusion: Our findings demonstrated a statistically significant decrease in volumetric flow rate in subjects using a knee scooter device with a flexed knee. Although venous stasis is a known risk factor for DVT, flow rate thresholds for increased thrombus formation are not well defined. The duration of scooter use, or flexed knee positioning, may have some effect on the degree of stasis. This finding should caution orthopedists to consider the risk attributed to the knee scooter as part of their overall patient assessment. Level of Evidence: Level II, therapeutic, comparative study.

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Park, H. M., and W. M. Lee. "Effect of viscoelasticity on the flow pattern and the volumetric flow rate in electroosmotic flows through a microchannel." Lab on a Chip 8, no. 7 (2008): 1163. http://dx.doi.org/10.1039/b800185e.

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Hawas, Malik, Nicolae Băran, and Antonio Detzortzis. "Influence of the Rotor Architecture and of the Speed on the Volumetric Efficiency of a New Type of Rotating Volumetric Machine." Advanced Materials Research 905 (April 2014): 487–91. http://dx.doi.org/10.4028/www.scientific.net/amr.905.487.

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In this paper the authors establish the calculus expression of the volume flow rate for a new type of working machine that can work as pump, fan or low pressure compressor.The calculation of volumetric efficiency is established for a new type of machine.The results of the experimental research on the influence of the speed on the volumetric flow rate of the machine are exposed.

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Correia, Mafalda, Jean Provost, Mickael Tanter, and Mathieu Pernot. "4D ultrafast ultrasound flow imaging:in vivoquantification of arterial volumetric flow rate in a single heartbeat." Physics in Medicine and Biology 61, no. 23 (November 3, 2016): L48—L61. http://dx.doi.org/10.1088/0031-9155/61/23/l48.

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Zhao, Gang, Jingyi Mi, Yongjun Rui, Xiaoyun Pan, Qun Yao, and Yang Qiu. "Correlation of volumetric flow rate and skin blood flow with cold intolerance in digital replantation." Medicine 96, no. 51 (December 2017): e9477. http://dx.doi.org/10.1097/md.0000000000009477.

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Gorchev, Aleksandr I., Aidar V. Mingaleev, and Anatoly B. Yakovlev. "State primary standard of gas volumetric and mass flow rate units GET 118-2017: history of creation, confirmation of calibration and measurement capabilities." Izmeritel`naya Tekhnika, no. 7 (2021): 22–26. http://dx.doi.org/10.32446/0368-1025it.2021-7-22-26.

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The history of the creation of the State primary standard of gas volumetric and mass flow rate units GET 118-2017 is presented. The significant role of international comparisons was noted at various stages of the creation of GET 118-2017: the comparisons results confirmed and made it possible to include in the KCDB the calibration and measurement capabilities of the Russian Federation in the field of gas volumetric flow measurements, and also helped to determine the direction and list of measures to improve the standard. A patented comparison method for calibrating critical nozzles, implemented in GET 118-2017 for transfer the units of volumetric and mass flow rates of gas to working standards, is described. The design, composition and characteristics of GET 118-2017 are presented. Currently, more than 700 working standards of gas volumetric and mass flow rates used in the Russian Federation and some KOOMET member countries are traced to GET 118-2017, the total number of calls to GET 118-2017 for the transfer of measurement units exceeds 3500 per year.

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Noreen, Saima, Sadia Waheed, Abid Hussanan, and Dianchen Lu. "Analytical Solution for Heat Transfer in Electroosmotic Flow of a Carreau Fluid in a Wavy Microchannel." Applied Sciences 9, no. 20 (October 16, 2019): 4359. http://dx.doi.org/10.3390/app9204359.

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This article explores the heat and transport characteristics of electroosmotic flow augmented with peristaltic transport of incompressible Carreau fluid in a wavy microchannel. In order to determine the energy distribution, viscous dissipation is reckoned. Debye Hückel linearization and long wavelength assumptions are adopted. Resulting non-linear problem is analytically solved to examine the distribution and variation in velocity, temperature and volumetric flow rate within the Carreau fluid flow pattern through perturbation technique. This model is also suitable for a wide range of biological microfluidic applications and variation in velocity, temperature and volumetric flow rate within the Carreau fluid flow pattern.

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Smith, K. L., M. S. Alexander, and J. P. W. Stark. "Voltage effects on the volumetric flow rate in cone-jet mode electrospraying." Journal of Applied Physics 99, no. 6 (March 15, 2006): 064909. http://dx.doi.org/10.1063/1.2183351.

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Rowland, Scott K., and George PL Walker. "Pahoehoe and aa in Hawaii: volumetric flow rate controls the lava structure." Bulletin of Volcanology 52, no. 8 (November 1990): 615–28. http://dx.doi.org/10.1007/bf00301212.

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35

Manzhai, V. N., and A. V. Ilyushnikov. "Volumetric rate of a turbulent newtonian fluid flow in a cylindrical channel." Journal of Engineering Physics and Thermophysics 81, no. 5 (September 2008): 893–96. http://dx.doi.org/10.1007/s10891-009-0124-x.

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Bingxiang, Long, Chen Qin, Ren Zebin, and Liao Daxiong. "Volumetric entropy generation rate associated with tip clearance flow in linear cascade." IOP Conference Series: Materials Science and Engineering 1081, no. 1 (February 1, 2021): 012045. http://dx.doi.org/10.1088/1757-899x/1081/1/012045.

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Tien, Tran Ngoc, and Nguyen Hong Thai. "A NOVEL DESIGN OF THE ROOTS BLOWER." Vietnam Journal of Science and Technology 57, no. 2 (April 5, 2019): 249. http://dx.doi.org/10.15625/2525-2518/57/2/13094.

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This paper reports a novel curve developed from non - circular gearing theory, which can be applied in rotor profile design of the two - lobe Roots blower. The formulas for calculating the volumetric efficiency and specific flow rate of the blower have also been established. To evaluate this type of the Roots blower, the volumetric efficiency and specific flow rate are being compared with those parameters of the two traditional designs and one recent variant.

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Ammerman, C. N., S. M. You, and Y. S. Hong. "Identification of Pool Boiling Heat Transfer Mechanisms From a Wire Immersed in Saturated FC-72 Using a Single-Photo/LDA Method." Journal of Heat Transfer 118, no. 1 (February 1, 1996): 117–23. http://dx.doi.org/10.1115/1.2824024.

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A unique method to determine the vapor volumetric flow rate above a heated wire utilizing a single photograph and laser-Doppler anemometry is developed and discussed. The volumetric flow rate is combined with additional analyses to determine the overall contributions to the total heat flux from four nucleate boiling heat transfer mechanisms (latent heat, natural convection, Marangoni flow, and microconvection). This method is applied to a 75-μm wire immersed in a saturated, highly wetting liquid (FC-72). Latent heat is identified as the dominant mechanism in the fully developed nucleate boiling regime.

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Khashi’ie, Najiyah Safwa, Norihan Md Arifin, and Ioan Pop. "Mixed Convective Stagnation Point Flow towards a Vertical Riga Plate in Hybrid Cu-Al2O3/Water Nanofluid." Mathematics 8, no. 6 (June 4, 2020): 912. http://dx.doi.org/10.3390/math8060912.

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The present work highlights the stagnation point flow with mixed convection induced by a Riga plate using a Cu-Al 2 O 3 /water hybrid nanofluid. The electromagnetohydrodynamic (EMHD) force generated from the Riga plate was influential in the heat transfer performance and applicable to delay the boundary layer separation. Similarity transformation was used to reduce the complexity of the governing model. MATLAB software, through the bvp4c function, was used to compute the resulting nonlinear ODEs. Pure forced convective flow has a distinctive solution, whereas two similarity solutions were attainable for the buoyancy assisting and opposing flows. The first solution was validated as the physical solution through the analysis of flow stability. The accretion of copper volumetric concentration inflated the heat transfer rate for the aiding and opposing flows. The heat transfer rate increased approximately up to an average of 10.216% when the copper volumetric concentration increased from 0.005 ( 0.5 % ) to 0.03 ( 3 % ) .

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Almoslh, Adel, Falah Alobaid, Christian Heinze, and Bernd Epple. "Influence of Pressure on Gas/Liquid Interfacial Area in a Tray Column." Applied Sciences 10, no. 13 (July 3, 2020): 4617. http://dx.doi.org/10.3390/app10134617.

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The influence of pressure on the gas/liquid interfacial area is investigated in the pressure range of 0.2–0.3 MPa by using a tray column test rig. A simulated waste gas, which consisted of 30% CO2 and 70% air, was used in this study. Distilled water was employed as an absorbent. The temperature of the inlet water was 19 °C. The inlet volumetric flow rate of water was 0.17 m3/h. Two series of experiments were performed; the first series was performed at inlet gas flow rate 15 Nm3/h, whereas the second series was at 20 Nm3/h of inlet gas flow rate. The results showed that the gas/liquid interfacial area decreases when the total pressure is increased. The effect of pressure on the gas/liquid interfacial area at high inlet volumetric gas flow rates is more significant than at low inlet volumetric gas flow rates. The authors studied the effect of decreasing the interfacial area on the performance of a tray column for CO2 capture.

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Abrar, Usama, Liu Shi, Nasif Raza Jaffri, Yi Kang, Muhammad Nawaz, and Zhu Huixian. "Estimate Mass Flow Rate of Dense Phased Powder Solids." E3S Web of Conferences 191 (2020): 04005. http://dx.doi.org/10.1051/e3sconf/202019104005.

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The complex multiphase gas-solid flow has always been a point of attraction for researchers over the past decade to explore the sensing techniques to sense and measure the mass flow. Weather dilute or dense phase flow, the gas-solid flow measurement generally requires velocity profile and volumetric concentration measurement to find the mass flow rate. The nature of the solids, the environmental factors-specially moisture adversely affects the sensor readings-specifically when it is non-invasive capacitive sensors. Gas-solid flow finds its applications in power plants, food, chemical, automobile, and pharmaceutical industries. This paper aims to explore the evolution of a novel approach of using load cell in conjunction with capacitive electrodes for calculating the mass flow rate of the solids.

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Ji, Jun, Hong Song, and Jiao Liu. "Micromixing Efficiency in High Gravity Reactor with Different Packing." Advanced Materials Research 233-235 (May 2011): 1184–87. http://dx.doi.org/10.4028/www.scientific.net/amr.233-235.1184.

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Micromixing efficiency in the high gravity(Higee) reactor with glass bead, rasching ring and pall ring was investigated respectively by using iodide-iodate test reaction as working system. The experimental results showed that segregation index of the Higee reactor increases while increasing volumetric flow ratio, size of pall ring and decreases with the increase of rotating rate, volumetric flow rate. The Micromixing efficiency of the Higee reactor with pall ring is better than glass bead and rasching ring.

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Xu, Hang, Huang Huang, Xiao-Hang Xu, and Qiang Sun. "Modeling heat transfer of nanofluid flow in microchannels with electrokinetic and slippery effects using Buongiorno’s model." International Journal of Numerical Methods for Heat & Fluid Flow 29, no. 8 (August 5, 2019): 2566–87. http://dx.doi.org/10.1108/hff-09-2018-0506.

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PurposeThis paper aims to study the heat transfer of nanofluid flow driven by the move of channel walls in a microchannel under the effects of the electrical double layer and slippery properties of channel walls. The distributions of velocity, temperature and nanoparticle volumetric concentration are analyzed under different slip-length. Also, the variation rates of flow velocity, temperature, concentration of nanoparticle, the pressure constant, the local volumetric entropy generation rate and the total cross-sectional entropy generation are analyzed.Design/methodology/approachA recently developed model is chosen which is robust and reasonable from the point of view of physics, as it does not impose nonphysical boundary conditions, for instance, the zero electrical potential in the middle plane of the channel or the artificial pressure constant. The governing equations of flow motion, energy, electrical double layer and stream potential are derived with slip boundary condition presented. The model is non-dimensionalized and solved by using the homotopy analysis method.FindingsSlip-length has significant influences on the velocity, temperature and nanoparticle volumetric concentration of the nanofluid. It also has strong effects on the pressure constant. With the increase of the slip-length, the pressure constant of the nanofluid in the horizontal microchannel decreases. Both the local volumetric entropy generation rate and total cross-sectional entropy generation rate are significantly affected by both the slip-length of the lower wall and the thermal diffusion. The local volumetric entropy generation rate at the upper wall is always higher than that around the lower wall. Also, the larger the slip-length is, the lower the total cross-sectional entropy generation rate is when the thermal diffusion is moderate.Originality/valueThe findings in this work on the heat transfer and flow phenomena of the nanofluid in microchannel are expected to make a contribution to guide the design of micro-electro-mechanical systems.

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Hu, Shengyong, Ao Zhang, Guorui Feng, Xiangqian Guo, Xuyang Miu, Chao Li, Dandan Han, Jin Wang, and Lixun Kang. "Methane Extraction from Abandoned Mines by Surface Vertical Wells: A Case Study in China." Geofluids 2018 (2018): 1–9. http://dx.doi.org/10.1155/2018/8043157.

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Considerable methane resources exist in abandoned coal mines. However, methane extraction from abandoned mines in China is still in the exploratory stage. This study presents technologies and engineering practices suitable for the extraction of gob methane from abandoned mines using surface vertical wells, including methane drainage systems, well bottom locations, and an intermittent drainage method. Seven surface wells in the Yongan abandoned mine in China were selected for gob methane extraction. Field results showed that the methane volumetric flow rate of a well whose bottom was close to the gob bottom was 2.5 times greater than that of a well with a bottom located in the gob fractured zone. Moreover, intermittent extraction can enable a well to extract methane cyclically at a high volumetric flow rate. A well drilled mistakenly into a coal pillar can be reused through hydraulic fracturing. The overall maximum methane volumetric flow rate, average concentration, and extraction span were 210 m3/h, 83%, and 1100 days, respectively.

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Szpica, Dariusz, Andrzej Borawski, Grzegorz Mieczkowski, Michał Kusznier, Mohamed M. Awad, Adel M. Sadik, and Mohammed Sallah. "Evaluation of the Influence of the Supply Pressure on Functional Parameters of the Impulse Low-Pressure Gas-Phase Injector." Acta Mechanica et Automatica 14, no. 4 (December 1, 2020): 180–85. http://dx.doi.org/10.2478/ama-2020-0026.

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Abstract The article presents research results referring to the influence of supply pressure on the functional parameters of the impulse low-pressure gas-phase injector. The study was done on the original stand for flow test of gas-phase injectors. In the indirect evaluation, with the initial parameters and the length of the forced impulse, the current line, acceleration and pressure sensor courses were used. Apart from the volumetric flow rate, the analysed parameters were the time periods of the injector opening and closing process. Those time segments were composed of response time and opening/closing time, the sum of which gives time of full opening. Functional relationships describing the volumetric flow rate, time of full opening and closing are presented, which are helpful not only in comparative tests of different injectors, but also in modelling the operation of gas injector or algorithms of gas supply control system. The reference to the volumetric flow rate allowed to indicate possible causes of variability of this parameter depending on the supply pressure.

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Kurdyumov, Yu A. "Enhancement of accuracy in volumetric flow rate measurements using flow transducers with a frequency output signal." Measurement Techniques 34, no. 7 (July 1991): 689–94. http://dx.doi.org/10.1007/bf00982061.

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Fiedorova, Klara, Martin Augustynek, and Marek Penhaker. "INFLUENCE OF THE USE OF GRAVITY SETS IN A PRESSURE VOLUMETRIC INFUSION PUMP WITH AN IMPACT ON THE ACCURACY OF INFUSION SOLUTION FLOWS." Lékař a technika - Clinician and Technology 50, no. 1 (March 31, 2020): 23–31. http://dx.doi.org/10.14311/ctj.2020.1.04.

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The subject of the work was the experimental verification of the negative influence of gravity sets in a pressure volumetric infusion pump with an impact on the accuracy of infusion solution dosing. The quality criterion for gravity sets was the accuracy of the flow versus the reference set by the volumetric infusion pump. The solution consisted of 14-hour measurements with two types of gravity sets, Intrafix® Primeline sets were used as universal sets and Standardline IS‑103 gravity sets. The insulin pump flow rate was set at 300 ml/h and 50 ml/h, and the actual flow rate of the infusion solution was recorded every hour using a graduated cylinder. Used gravity sets were also processed by mechanical tests, unused sets were subjected to these tests and the obtained data were compared with each other. Experiments carried out showed that at the set flow rate of 300 ml/h, the flow error with the universal set was -3% and at a set flow rate of 50 ml/h the error was +2.3%. Flow accuracy using gravity sets was worse, a flow error of -7.2% was detected for a flow rate of 50 ml/h and a flow error of -7.7% was measured for 300 ml/h. The volumetric pump used declares a tolerated inaccuracy of ± 3% when used with standard infusion sets. Based on the data, it can be concluded that the replacement of set types has an influence on the dosage of infusion solutions.

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Kim, Chul-Kyu, Sang-Moon Lee, and Choon-Man Jang. "Performance analysis of a ball valve used for gas pipelines by introducing nondimensional parameters." Advances in Mechanical Engineering 11, no. 1 (January 2019): 168781401882335. http://dx.doi.org/10.1177/1687814018823350.

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The present study deals with the performance characteristics of a ball valve used for gas pipelines by introducing nondimensional parameters. The ball valve has relatively complex flow characteristics on the inside and downstream of the valve, although it has a simple structure as compared with the other valves. The nondimensional parameters, which define the valve operating conditions, are introduced to analyze the nature of the physical properties due to the valve’s complex flow. To define the valve flow conditions with respect to valve size, seven nondimensional parameters were selected: pressure ratio, volumetric flow rate ratio, mass flow rate ratio, Reynolds number, Mach number, valve flow coefficient, and inherent flow coefficient. The open-loop type experimental setup is designed to measure the pressure drop and the volumetric flow rate of the ball valve according to the opening rate (angle) of the test valve. Based on the experimental data, obtained by the data acquisition system of the test rig, useful nondimensional parameters to define the nature of the valve performance have been selected and determined. Throughout the experimental analysis of the ball valve, it was found that the nondimensional parameters of pressure ratio, Reynolds number, and Mach number have a similar tendency as related to the valve performance. It can be seen that the intrinsic characteristics of the ball valve are represented by the selected nondimensional parameters, which are defined irrespective of the valve size. The authors proposed a quadratic polynomial for the volumetric flow rate ratio, and the mass flow rate ratio, and introduced the formula for predicting the inherent flow coefficient by the cubic approximation polynomial. It is noted that the nondimensional parameters of the ball valve can be used to determine the performance characteristics with respect to the valve-opening rate and size effectively.

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Ningsih, Erlinda, Abas Sato, Mochammad Alfan Nafiuddin, and Wisnu Setyo Putranto. "TOTAL VOLUMETRIC MASS TRANSFER COEFFICIENT AT CO2 GAS ABSORPTION USING K2CO3 BY MSG PROMOTER." Konversi 7, no. 1 (November 25, 2019): 6. http://dx.doi.org/10.20527/k.v7i1.4844.

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Abstract- One of the most widely used processes for CO2 gas removal is Absorption. Carbon dioxide is the result of the fuel combustion process which of the hazardous gases. The aim of this research is to determine the total mass transfer coefficient and analyze the effect of the absorbent flow rate of the absorbent solution with the promoter and the gas flow rate to the total mass transfer coefficient value. The variables consisted of liquid flow rate: 1, 2, 3, 4, 5 liter/min, gas flow rate: 15, 25, 30, 40, 50 liter/min and MSG concentration: 0%, 1%, 3% and 5% by weight. The solution of Pottasium Carbonate as absorbent with MSG promoter is flowed through top column and CO2 gas flowed from bottom packed column. Liquids were analyzed by titration and the gas output was analyzed by GC. From this research, it is found that the flow rate of gas and the liquid flow rate is directly proportional to the value of KGa. The liquid flow rate variable 5 liters / minute, gas flow rate 15 l / min obtained value of KGa 11,1102 at concentration of MSG 5%. Keywords: Absorption, CO2, K2CO3, MSG.

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Tariq, Hussain, Ahmad Shoukat, Muhammad Anwar, Asif Israr, and Hafiz Ali. "Water cooled micro-hole cellular structure as a heat dissipation media: An experimental and numerical study." Thermal Science 24, no. 2 Part A (2020): 683–92. http://dx.doi.org/10.2298/tsci180219184t.

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Thermal performance of micro-hole cellular structure using water as a cool?ing fluid was investigated through CFD and then numerical results were validated with the experimental results. The minimum base temperature for the micro-hole cellular structure was found to be 29.7?C and 32.3?C numerically and experimentally, respectively, with volumetric flow rate of 0.000034 m3/s (2 Lpm) at a heating power of 345 W. Numerical values of the base temperature are in close agreement with experimental results with an error of 8.75%. Previously, the base temperatures of heat sinks using alumina nanofluid with 1% of volumetric concentration and water with volumetric flow rate of 0.000017 m3/s (1 Lpm) have been reported to be 43.9?C and 40.5?C, respectively.

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Journal articles on the topic 'Volumetric flow rate'

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