A general correlation for two-phase pressure drop in intermittent flow of gas and non-Newtonian liquid mixtures in a pipe

1996 ◽  
Vol 22 ◽  
pp. 101 ◽  
Author(s):  
M Dziubinski
Keyword(s):  
Pressure Drop ◽  
Liquid Mixtures ◽  
Newtonian Liquid ◽  
Intermittent Flow ◽  
Two Phase ◽  
General Correlation ◽  
Phase Pressure

Frictional Pressure Drop of Gas-Newtonian and Gas-Non Newtonian Slug Flow in Vertical Pipe

2011 ◽  
Vol 9 (1) ◽  
Author(s):  
Subrata Kumar Majumder ◽  
Sandip Ghosh ◽  
Gautam Kundu ◽  
Arun Kumar Mitra
Keyword(s):  
Pressure Drop ◽  
Slug Flow ◽  
Amyl Alcohol ◽  
Newtonian Liquid ◽  
Vertical Pipe ◽  
Two Phase ◽  
Vertical Column ◽  
Frictional Pressure Drop ◽  
Liquid Systems ◽  
Phase Pressure

Experimental study on two-phase pressure drop in a vertical pipe with air-Newtonian and non-Newtonian liquid in slug flow regime has been carried out within a range of gas and liquid flowrate of 0.5×10-4 to 1.92×10-4 m-3/s and 1.6×10-4 to 6.7×10-4 m3/s respectively. In the present study air and four types of liquids such as water, amyl alcohol, glycerin (two different concentrations), and CMC (Sodium Carboxymethyl Cellulose) are used. The present data were analyzed by two-phase friction method. To predict the two-phase pressure drop, correlations have been developed with Newtonian and non-Newtonian liquid. A general correlation was also developed to predict the two-phase pressure drop in a vertical column of diameter 0.01905 m and 3.4 m height combining both the Newtonian and non-Newtonian liquid systems.

scholarly journals Two-phase pressure drop for gas and non-Newtonian liquid flows through circular microchannel

2017 ◽  
Vol 83 (847) ◽  
pp. 16-00386-16-00386
Author(s):  
Akimaro KAWAHARA ◽  
Akifumi MORI ◽  
Wen Zhe LAW ◽  
Yukihiro YONEMOTO ◽  
Mohamed H. MANSOUR ◽  
...  
Keyword(s):  
Pressure Drop ◽  
Newtonian Liquid ◽  
Two Phase ◽  
Circular Microchannel ◽  
Liquid Flows ◽  
Phase Pressure

Modeling of Pressure Drop During Condensation in Circular and Noncircular Microchannels

2008 ◽  
Vol 131 (1) ◽  
Author(s):  
Akhil Agarwal ◽  
Srinivas Garimella
Keyword(s):  
Pressure Drop ◽  
Flow Regime ◽  
Intermittent Flow ◽  
Condensation Process ◽  
International Institute ◽  
Two Phase ◽  
Pressure Drops ◽  
Smooth Transitions ◽  
Phase Pressure ◽  
Circular Microchannels

This paper presents a multiple flow-regime model for pressure drop during condensation of refrigerant R134a in horizontal microchannels. Condensation pressure drops measured in two circular and six noncircular channels ranging in hydraulic diameter from 0.42mmto0.8mm are considered here. For each tube under consideration, pressure drop measurements were taken over the entire range of qualities from 100% vapor to 100% liquid for five different refrigerant mass fluxes between 150kg∕m2s and 750kg∕m2s. Results from previous work by the authors on condensation flow mechanisms in microchannel geometries were used to assign the applicable flow regime to the data points. Garimella et al. (2005, “Condensation Pressure Drop in Circular Microchannels,” Heat Transfer Eng., 26(3) pp. 1–8) reported a comprehensive model for circular tubes that addresses the progression of the condensation process from the vapor phase to the liquid phase by modifying and combining the pressure drop models for intermittent (Garimella et al., 2002, “An Experimentally Validated Model for Two-Phase Pressure Drop in the Intermittent Flow Regime for Circular Microchannels,” ASME J. Fluids Eng., 124(1), pp. 205–214) and annular (Garimella et al., 2003, “Two-Phase Pressure Drops in the Annular Flow Regime in Circular Microchannels,” 21st IIR International Congress of Refrigeration, International Institute of Refrigeration, p. ICR0360) flows reported earlier by them. This paper presents new condensation pressure drop data on six noncircular channels over the same flow conditions as the previous work on circular channels. In addition, a multiple flow-regime model similar to that developed earlier by Garimella et al. for circular microchannels is developed here for these new cross sections. This combined model accurately predicts condensation pressure drops in the annular, disperse-wave, mist, discrete-wave, and intermittent flow regimes for both circular and noncircular microchannels of similar hydraulic diameters. Overlap and transition regions between the respective regimes are also addressed to yield relatively smooth transitions between the predicted pressure drops. The resulting model predicts 80% of the data within ±25%. The effect of tube shape on pressure drop is also demonstrated.

Two-Phase Pressure Drop in the Intermittent Flow Regime for Noncircular Microchannels

2002 ◽  
Author(s):  
Srinivas Garimella ◽  
Jesse D. Killion ◽  
John W. Coleman
Keyword(s):  
Pressure Drop ◽  
Flow Regime ◽  
Intermittent Flow ◽  
Average Error ◽  
Two Phase ◽  
Pressure Drops ◽  
Mass Fluxes ◽  
Tube Shape ◽  
Measured Pressure ◽  
Phase Pressure

This paper reports the development of an experimentally validated model for pressure drop during intermittent flow of condensing refrigerant R134a in horizontal, noncircular microchannels. Two-phase pressure drops were measured in six noncircular channels ranging in hydraulic diameter from 0.42 mm to 0.84 mm. The tube shapes included square, rectangular, triangular, barrel-shaped, and others. For each tube under consideration, pressure drop measurements were taken over the entire range of qualities from vapor to liquid at five different refrigerant mass fluxes between 150 kg/m2s and 750 kg/m2s. Results from previous work by the authors were used to select the data that correspond to the intermittent flow regime; generally, these points had qualities less than 25%. The pressure drop model previously developed by the authors for circular microchannels was used as the basis for the model presented in this paper. The model includes the contributions of the liquid slug, the vapor bubble, and the transitions between the bubbles and slugs. Slug frequency was estimated using a simple correlation for non-dimensional unit-cell length. The model predicts the experimentally measured pressure drops for the noncircular tube shapes under consideration with 90% of the predictions within ±28% of the measurements (average error 16.5%), which is shown to be much better than the predictions of other models in the literature. The effects of tube shape on condensation pressure drop are also illustrated in the paper.

An Experimentally Validated Model for Two-Phase Pressure Drop in the Intermittent Flow Regime for Circular Microchannels

2001 ◽  
Vol 124 (1) ◽  
pp. 205-214 ◽  
Author(s):  
S. Garimella ◽  
J. D. Killion ◽  
J. W. Coleman
Keyword(s):  
Pressure Drop ◽  
Flow Regime ◽  
Vapor Bubble ◽  
Total Pressure ◽  
Measured Data ◽  
Unit Cell ◽  
Intermittent Flow ◽  
Liquid Slug ◽  
Two Phase ◽  
Phase Pressure

This paper reports the development of an experimentally validated model for pressure drop during intermittent flow of condensing refrigerant R134a in horizontal microchannels. Two-phase pressure drops were measured in five circular channels ranging in hydraulic diameter from 0.5 mm to 4.91 mm. For each tube under consideration, pressure drop measurements were first taken over the entire range of qualities from 100% vapor to 100% liquid. In addition, the tests for each tube were conducted for five different refrigerant mass fluxes between 150 kg/m2-s and 750 kg/m2-s. Results from previous work by the authors on condensation flow mechanisms in microchannel geometries were then used to identify data that corresponded to the intermittent flow regime. A pressure drop model was developed for a unit cell in the channel based on the observed slug/bubble flow pattern for these conditions. The unit cell comprises a liquid slug followed by a vapor bubble that is surrounded by a thin, annular liquid film. Contributions of the liquid slug, the vapor bubble, and the flow of liquid between the film and slug to the pressure drop were included. Empirical data from the literature for the relative length and velocity of the slugs and bubbles, and relationships from the literature for the pressure loss associated with the mixing that occurs between the slug and film were used with assumptions about individual phase friction factors, to estimate the total pressure drop in each unit cell. A simple correlation for non-dimensional unit-cell length based on slug Reynolds number was then used to estimate the total pressure drop. The results from this model were on average within ±13.4% of the measured data, with 88% of the predicted results within ±25% of the 77 measured data points.

Sign in / Sign up

Export Citation Format

Share Document