Prediction of effective friction factors for single-phase flow in horizontal microfin tubes

2004 ◽  
Vol 27 (8) ◽  
pp. 904-913 ◽  
Author(s):  
H.S. Wang ◽  
J.W. Rose
Keyword(s):  
Single Phase ◽  
Phase Flow ◽  
Single Phase Flow ◽  
Friction Factors ◽  
Microfin Tubes ◽  
Effective Friction

Frictional Pressure Drop Correlations for Single-Phase Flow, Condensation, and Evaporation in Microfin Tubes

2015 ◽  
Vol 138 (2) ◽  
Author(s):  
Zan Wu ◽  
Bengt Sundén
Keyword(s):  
Reynolds Number ◽  
Pressure Drop ◽  
Single Phase ◽  
Flow Boiling ◽  
Phase Flow ◽  
Single Phase Flow ◽  
Frictional Pressure Drop ◽  
Friction Factors ◽  
Flow Condensation ◽  
Microfin Tubes

Experimental single-phase, condensation, and evaporation (flow boiling) pressure drop data from the literature and our previous studies were collected to evaluate previous frictional pressure drop correlations for horizontal microfin tubes of different geometries. The modified Ravigururajan and Bergles correlation, by adopting the Churchill model to calculate the smooth-tube friction factor and by using the hydraulic diameter in the Reynolds number, can predict single-phase turbulent frictional pressure drop data relatively well. Eleven pressure drop correlations were evaluated by the collected database for condensation and evaporation. Correlations originally developed for condensation and evaporation in smooth tubes can be suitable for microfin tubes if the friction factors in the correlations were calculated by the Churchill model to include microfin effects. The three most accurate correlations were recommended for condensation and evaporation in microfin tubes. The Cavallini et al. correlation and the modified Friedel correlation can give good predictions for both condensation and evaporation. However, some inconsistencies were found, even for the recommended correlations.

Frictional Pressure Drop Correlations for Single-Phase Flow, Condensation and Evaporation in Microfin Tubes

2014 ◽  
Author(s):  
Zan Wu ◽  
Bengt Sundén
Keyword(s):  
Reynolds Number ◽  
Pressure Drop ◽  
Single Phase ◽  
Flow Boiling ◽  
Phase Flow ◽  
Single Phase Flow ◽  
Frictional Pressure Drop ◽  
Friction Factors ◽  
Flow Condensation ◽  
Microfin Tubes

Experimental single-phase, condensation and evaporation (flow boiling) pressure drop data from the literature and our previous studies were collected to evaluate previous frictional pressure drop correlations for horizontal microfin tubes of different geometries. The modified Ravigururajan and Bergles correlation, by adopting the Churchill model to calculate the smooth-tube friction factor and by using the hydraulic diameter in the Reynolds number, can predict single-phase turbulent frictional pressure drop data relatively well. Eleven pressure drop correlations were evaluated by the collected database for condensation and evaporation. Correlations originally developed for condensation and evaporation in smooth tubes can be suitable for microfin tubes if the friction factors in the correlations were calculated by the Churchill model to include microfin effects. The three most accurate correlations were recommended for condensation and evaporation in microfin tubes, respectively. The Cavallini et al. correlation and the modified Friedel correlation can give good predictions for both condensation and evaporation. However, some inconsistencies were found, even for the recommended correlations.

Single-Phase and Two-Phase Flow Pressure Drop in a Long Double Helicoidally-Coiled Tube

2021 ◽  
Author(s):  
Veera Manek ◽  
Tao Fang ◽  
S. Mostafa Ghiaasiaan ◽  
Jeff Patelczyk
Keyword(s):  
Experimental Data ◽  
Pressure Drop ◽  
Single Phase ◽  
Two Phase Flow ◽  
Reynolds Numbers ◽  
Phase Flow ◽  
Single Phase Flow ◽  
Two Phase ◽  
Friction Factors ◽  
Flow Experiments

Abstract Single-phase and two-phase frictional pressure drop in horizontally-oriented double helically coiled tubes confined in a cylindrical shell is experimentally studied using an instrumented test loop that represents a prototypical liquified natural gas (LNG) fuel delivery system for internal combustion (IC) engines. Adiabatic experimental data addressing liquid (water) and gas (nitrogen) single-phase flows, as well as two-phase flows (air-water) in the helicoidally coiled tubes are presented. The range of Reynolds numbers for single-phase flow experiments is 2600 to 4800. In two-phase flow experiments the liquid-only and gas-only Reynolds numbers varied in 1030 to 6600 and 1700 to 17700 ranges, respectively. In laminar single-phase flow regime the measured friction factors are in relatively good agreement with well-established correlations. In the turbulent flow regime the measured friction factors are moderately higher than the prediction of well-established published correlations. Two-phase flow frictional pressure drops are compared with some relevant correlations, with poor agreement. The generated experimental data are empirically correlated based on the two-phase flow multiplier concept.

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