scholarly journals Measurements, error analyses, and calculations of water and steam individual mass flow rates, velocities, and related flow parameters obtained from single-phase and two-phase prototype tests of the PKL instrumented spool pieces for the US NRC-RSR 3-D program

1979 ◽  
Author(s):  
W. Stein
Keyword(s):  
Mass Flow ◽  
Single Phase ◽  
Two Phase ◽  
Flow Rates ◽  
Flow Parameters ◽  
Error Analyses ◽  
The Us ◽  
Mass Flow Rates ◽  
Individual Mass

A NEW METHOD OF MEASURING TWO-PHASE MASS FLOW RATES IN A VENTURI

2009 ◽  
Vol 21 (1-2) ◽  
pp. 157-168 ◽  
Author(s):  
He Peixiang ◽  
Cees W. M. van der Geld ◽  
Claudio Alimonti ◽  
Julio Cesar Passos
Keyword(s):  
Mass Flow ◽  
New Method ◽  
Two Phase ◽  
Flow Rates ◽  
Mass Flow Rates

Evaluation of Geometry-Dependent Spray Hole Individual Mass Flow Rates of Multi-Hole High-Pressure GDI-Injectors Utilizing a Novel Measurement Setup

2020 ◽  
Author(s):  
Maximilian Miller ◽  
Maximilian Kuhnhenn ◽  
Ingo Samerski ◽  
Grazia Lamanna ◽  
Bernhard Weigand
Keyword(s):  
High Pressure ◽  
Mass Flow ◽  
Flow Rates ◽  
Mass Flow Rates ◽  
Individual Mass

Shell and tube heat exchanger thermal-hydraulic analysis equipped with baffles and corrugated tubes filled with non-Newtonian two-phase nanofluid

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ali Akbar Abbasian Arani ◽  
Reza Moradi
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Heat Exchanger ◽  
Transfer Coefficient ◽  
Mass Flow ◽  
Two Phase ◽  
Flow Rates ◽  
Content Type ◽  
Mass Flow Rates ◽  
Shell And Tube

Purpose Using turbulators, obstacles, ribs, corrugations, baffles and different tube geometry, and also various arrangements of these components have a noticeable effect on the shell and tube heat exchangers (STHEs) thermal-hydraulic performance. This study aims to investigate non-Newtonian fluid flow characteristics and heat transfer features of water and carboxyl methyl cellulose (H2O 99.5%:0.5% CMC)-based Al2O3 nanofluid inside the STHE equipped with corrugated tubes and baffles using two-phase mixture model. Design/methodology/approach Five different corrugated tubes and two baffle shapes are studied numerically using finite volume method based on SIMPLEC algorithm using ANSYS-Fluent software. Findings Based on the obtained results, it is shown that for low-mass flow rates, the disk baffle (DB) has more heat transfer coefficient than that of segmental baffle (SB) configuration, while for mass flow rate more than 1 kg/s, using the SB leads to more heat transfer coefficient than that of DB configuration. Using the DB leads to higher thermal-hydraulic performance evaluation criteria (THPEC) than that of SB configuration in heat exchanger. The THPEC values are between 1.32 and 1.45. Originality/value Using inner, outer or inner/outer corrugations (outer circular rib and inner circular rib [OCR+ICR]) tubes for all mass flow rates can increase the THPEC significantly. Based on the present study, STHE with DB and OCR+ICR tubes configuration filled with water/CMC/Al2O3 with f = 1.5% and dnp = 100 nm is the optimum configuration. The value of THPEC in referred case was 1.73, while for outer corrugations and inner smooth, this value is between 1.34 and 1.57, and for outer smooth and inner corrugations, this value is between 1.33 and 1.52.

Multiphase Flow Measurement Techniques—A Review

1993 ◽  
Vol 115 (3) ◽  
pp. 151-161 ◽  
Author(s):  
V. S. V. Rajan ◽  
R. K. Ridley ◽  
K. G. Rafa
Keyword(s):  
Multiphase Flow ◽  
Mass Flow ◽  
Measurement Techniques ◽  
Extensive Literature ◽  
Two Phase ◽  
Flow Rates ◽  
Gas Phases ◽  
Mass Flow Rates ◽  
The Individual ◽  
Areas Of Interest

This paper is a review of current techniques available for measuring the velocity and composition in multiphase streams, to obtain the mass flow rate of the individual phases. An extensive literature search was conducted on the topic and related areas of interest. The major difficulty in measuring both the velocity and composition of multiphase streams is in dealing with the wide variety of flow regimes which are possible in multiphase flow in pipes. A device which is suitable for accurate velocity measurement in multiphase flows is not commercially available. However, if the flow is well mixed, it should be possible to calibrate a simple device, such as a nozzle or a venturi, to provide accurate total volumetric flow rates. Several commercial in-line static mixing devices are suitable for low gas concentrations (≤ 10 percent) and with superficial gas velocities higher than 10 m/s. For lower gas velocities and high gas concentrations, the suitability of these in-line mixers will have to be further assessed experimentally. Other techniques such as cross-correlation are known for two-phase flow velocity measurements, and the results of these applications look promising. A multiphase compositional meter to monitor the concentration of oil, water, and gas phases flowing in a pipeline, used in combination with a suitable homogenizer and a velocity meter, would facilitate measurement of the mass flow rates of the individual phases. Further work must be done to develop this concept.

Bounds on Two-Phase Flow: Part II — Void Fraction in Circular Pipes

2005 ◽  
Author(s):  
M. M. Awad ◽  
Y. S. Muzychka
Keyword(s):  
Experimental Data ◽  
Void Fraction ◽  
Mass Flow ◽  
Liquid Fraction ◽  
Published Data ◽  
Phase Flow ◽  
Two Phase ◽  
Flow Rates ◽  
Working Fluids ◽  
Mass Flow Rates

Theoretical and empirical models for the gas void fraction (α) are reviewed. Simple rules are developed for obtaining rational bounds for the void fraction in two-phase flow. The lower bound is based on the separate cylinders formulation for turbulent-turbulent flow that uses the Blasius equation to predict the Fanning friction factor. The upper bound is based on the Butterworth relationship that represents well the Lockhart-Martinelli correlation. These two bounds are reversed in the case of liquid fraction (1−α). The bounds models are verified using published experimental data of void fraction versus mass quality at constant mass flow rate. The published data include different working fluids such as R-12 and R-22 at different pipe diameters, different pressures, and different mass flow rates. It is shown that the published data can be well bounded for a wide range of mass qualities, pipe diameters, pressures and mass flow rates. Further comparisons are made using the published experimental data of void fraction (α) and liquid fraction (1−α) versus the Lockhart-Martinelli parameter (X), for different working fluids such as R-12, R-22 and air-water mixtures.

Characteristics of the Hydrodynamic Coefficient for Flow of a Steam-Water Mixture in a Pebble Bed

2006 ◽  
Vol 129 (9) ◽  
pp. 1291-1294 ◽  
Author(s):  
Alexandr A. Avdeev ◽  
Boris F. Balunov ◽  
Rostislav A. Rybin ◽  
Ruslan I. Soviev ◽  
Yuri B. Zudin
Keyword(s):  
Water Flow ◽  
Mass Flow ◽  
Pressure Loss ◽  
Single Phase ◽  
Water Mixture ◽  
Pebble Bed ◽  
Hydrodynamic Coefficient ◽  
Flow Rates ◽  
Wide Range ◽  
Mass Flow Rates

Pressure loss for flow of a steam-water mixture in a pebble bed is experimentally investigated (the first stage of the study was described in Avdeev, et al., 2003 [High Temp., 41, pp. 371–383]). The measurements of the care performed within the wide range of regime parameters: pressures of 0.9-15.6MPa, mass-flow rates of 107-770kg∕(m2s) and steam quality of 0–0.49. The experimental data for the pressure loss of single-phase air and water flows were used as reference data. The final results are represented in the form of the ratio of the pressure loss for the steam-water flow to that for the single-phase water flow at identical mass-flow rates.

scholarly journals Net-exergetic, hydraulic and thermal optimization of coaxial heat exchangers using fixed flow conditions instead of fixed flow rates

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Tobias Blanke ◽  
Markus Hagenkamp ◽  
Bernd Döring ◽  
Joachim Göttsche ◽  
Vitali Reger ◽  
...  
Keyword(s):  
Reynolds Number ◽  
Laminar Flow ◽  
Mass Flow ◽  
Flow Rate ◽  
Heat Exchangers ◽  
Circular Ring ◽  
Flow Conditions ◽  
Flow Rates ◽  
Mass Flow Rates ◽  
Pipe Radius

AbstractPrevious studies optimized the dimensions of coaxial heat exchangers using constant mass flow rates as a boundary condition. They show a thermal optimal circular ring width of nearly zero. Hydraulically optimal is an inner to outer pipe radius ratio of 0.65 for turbulent and 0.68 for laminar flow types. In contrast, in this study, flow conditions in the circular ring are kept constant (a set of fixed Reynolds numbers) during optimization. This approach ensures fixed flow conditions and prevents inappropriately high or low mass flow rates. The optimization is carried out for three objectives: Maximum energy gain, minimum hydraulic effort and eventually optimum net-exergy balance. The optimization changes the inner pipe radius and mass flow rate but not the Reynolds number of the circular ring. The thermal calculations base on Hellström’s borehole resistance and the hydraulic optimization on individually calculated linear loss of head coefficients. Increasing the inner pipe radius results in decreased hydraulic losses in the inner pipe but increased losses in the circular ring. The net-exergy difference is a key performance indicator and combines thermal and hydraulic calculations. It is the difference between thermal exergy flux and hydraulic effort. The Reynolds number in the circular ring is instead of the mass flow rate constant during all optimizations. The result from a thermal perspective is an optimal width of the circular ring of nearly zero. The hydraulically optimal inner pipe radius is 54% of the outer pipe radius for laminar flow and 60% for turbulent flow scenarios. Net-exergetic optimization shows a predominant influence of hydraulic losses, especially for small temperature gains. The exact result depends on the earth’s thermal properties and the flow type. Conclusively, coaxial geothermal probes’ design should focus on the hydraulic optimum and take the thermal optimum as a secondary criterion due to the dominating hydraulics.

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