A Mechanistic Heat Transfer Correlation for Non-Boiling Two-Phase Flow in Horizontal, Inclined and Vertical Pipes

2011 ◽  
Author(s):  
Clement C. Tang ◽  
Afshin J. Ghajar
Keyword(s):  
Heat Transfer ◽  
Friction Factor ◽  
Two Phase Flow ◽  
Mechanistic Model ◽  
Local Heat Transfer ◽  
Phase Flow ◽  
Heat Transfer Correlation ◽  
Transfer Coefficients ◽  
Two Phase ◽  
Transfer Data

A mechanistic heat transfer correlation is proposed to estimate heat transfer coefficient for non-boiling two-phase flow in horizontal, slightly inclined, and vertical pipes using the analogy between friction factor and heat transfer. Local heat transfer coefficients, pressure drops and flow parameters were measured for air-water flow in a 27.9 mm stainless steel pipe. The heat transfer and pressure drop data were collected by carefully coordinating the gas and liquid superficial Reynolds numbers. The proposed mechanistic correlation is validated by using experimentally measured heat transfer data. Evaluation of the mechanistic correlation with the measured heat transfer data indicated that the analogy between friction factor and heat transfer can be used with reasonable accuracy for heat transfer predictions in non-boiling two-phase pipe flow. Comparison with experimental results showed that the bulk of the data points were predicted within ±30% by the mechanistic model.

A Mechanistic Model for Predicting Heat and Mass Transfer in Vertical Two-Phase Flow

Volume 3 ◽  
2004 ◽  
Author(s):  
Siamack A. Shirazi ◽  
Ebrahin Al-Adsani ◽  
John R. Shadley ◽  
Edmund F. Rybicki
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Two Phase Flow ◽  
Mechanistic Model ◽  
Intermittent Flow ◽  
Phase Flow ◽  
Empirical Correlations ◽  
Transfer Coefficients ◽  
Two Phase

The mass transfer coefficient plays an important role in predicting corrosion rates. Using similarities between heat and mass transfer mechanisms, a mechanistic model is proposed to predict heat and mass transfer coefficients for two-phase flow in vertical pipes. The mechanistic model is evaluated by using water-air heat transfer experimental data obtained from the literature. The mechanistic model is also compared with commonly used empirical correlations. In comparison with available heat transfer correlations, the mechanistic model performs very well for vertical annular flow, bubbly flow and slug or intermittent flow that were considered. The mechanistic model is based on physics of two-phase flow and thus is expected to be more general than empirical correlations.

Validation of a General Heat Transfer Correlation for Non-Boiling Two-Phase Flow With Different Flow Patterns and Pipe Inclination Angles

2007 ◽  
Author(s):  
Clement C. Tang ◽  
Afshin J. Ghajar
Keyword(s):  
Heat Transfer ◽  
Void Fraction ◽  
Two Phase Flow ◽  
Flow Patterns ◽  
Phase Flow ◽  
Heat Transfer Correlation ◽  
Two Phase ◽  
Transfer Data ◽  
Inclination Angles ◽  
Data Points

A general heat transfer correlation for non-boiling gas-liquid two-phase flow with different flow patterns and inclination angles was developed. To verify the correlation, local heat transfer coefficients and flow parameters were measured for air-water flow in a pipe for the horizontal and slightly upward inclined (2°, 5°, and 7°) positions, and all the flow patterns in the entire flow map. The test section was a 27.9 mm stainless steel pipe with a length to diameter ratio of 95. A total of 763 data points were collected for horizontal and slightly upward inclined positions by carefully coordinating the liquid and gas superficial Reynolds number combinations. The heat transfer data were collected under a uniform wall heat flux boundary condition ranging from about 1800 to 10900 W/m2. The superficial Reynolds numbers ranged from about 740 to 26000 for water and from about 560 to 48000 for air. The general heat transfer correlation was validated with the 763 data points that were experimentally collected. The validation confirmed the robustness of the general two-phase heat transfer correlation to adequately predict heat transfer data for various flow patterns and inclination angles. The accuracy of the correlation to correlate the experimental data was further explored by applying various available void fraction correlations. The performance of the correlation when applied with the different void fraction correlations were compared and appropriate recommendations are made.

Experimental Study on Heat Transfer of Single-Phase Flow and Boiling Two-Phase Flow in Vertical Narrow Annuli

2002 ◽  
Author(s):  
Suizheng Qiu ◽  
Minoru Takahashi ◽  
Guanghui Su ◽  
Dounan Jia
Keyword(s):  
Heat Transfer ◽  
Single Phase ◽  
Two Phase Flow ◽  
Annular Channel ◽  
Phase Flow ◽  
Single Phase Flow ◽  
Transfer Coefficients ◽  
Two Phase ◽  
Narrow Annuli ◽  
Narrow Gaps

Water single-phase and nucleate boiling heat transfer were experimentally investigated in vertical annuli with narrow gaps. The experimental data about water single-phase flow and boiling two-phase flow heat transfer in narrow annular channel were accumulated by two test sections with the narrow gaps of 1.0mm and 1.5mm. Empirical correlations to predict the heat transfer of the single-phase flow and boiling two-phase flow in the narrow annular channel were obtained, which were arranged in the forms of the Dittus-Boelter for heat transfer coefficients in a single-phase flow and the Jens-Lottes formula for a boiling two-phase flow in normal tubes, respectively. The mechanism of the difference between the normal channel and narrow annular channel were also explored. From experimental results, it was found that the turbulent heat transfer coefficients in narrow gaps are nearly the same to the normal channel in the experimental range, and the transition Reynolds number from a laminar flow to a turbulent flow in narrow annuli was much lower than that in normal channel, whereas the boiling heat transfer in narrow annular gap was greatly enhanced compared with the normal channel.

scholarly journals Two-dimensional heat transfer coefficients with simultaneous flow visualisations during two-phase flow boiling in a PDMS microchannel

2018 ◽  
Vol 130 ◽  
pp. 624-636 ◽  
Author(s):  
Sofia Korniliou ◽  
Coinneach Mackenzie-Dover ◽  
John R.E. Christy ◽  
Souad Harmand ◽  
Anthony J. Walton ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Two Phase Flow ◽  
Flow Boiling ◽  
Phase Flow ◽  
Two Dimensional ◽  
Transfer Coefficients ◽  
Two Phase ◽  
Heat Transfer Coefficients ◽  
Pdms Microchannel

scholarly journals Two-phase flow pattern and heat transfer coefficients of R245fa/R134a under non-uniform heat flux

2019 ◽  
Vol 65 (17) ◽  
pp. 1741-1751
Author(s):  
Yani Lu ◽  
Li Zhao ◽  
Shuai Deng ◽  
Dongpeng Zhao ◽  
Xianhua Nie ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Flow Pattern ◽  
Two Phase Flow ◽  
Uniform Heat Flux ◽  
Phase Flow ◽  
Transfer Coefficients ◽  
Two Phase ◽  
Heat Transfer Coefficients ◽  
Uniform Heat

scholarly journals ENHANCEMENT THE HEAT TRANSFER FOR TWO-PHASE FLOW THROUGH A RECTANGULAR RIBBED VERTICAL CHANNEL

2018 ◽  
Vol 18 (1) ◽  
pp. 92-109
Author(s):  
Riyadh S Al-Turaihi ◽  
Doaa F Kareem
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Two Phase Flow ◽  
Vertical Channel ◽  
Numerical Data ◽  
Local Heat Transfer ◽  
Local Heat ◽  
Phase Flow ◽  
Two Phase

 The heat transfer coefficient and temperature distribution of two phase flow (water, air)in rectangular ribbed vertical channel was investigated experimentally and numerically inthis work for different values of water and air superficial velocities (0.0421, 0.0842, 0.1158,0.1474 and 0.1684 m/s) and (1.0964, 1.425, 1.644, 1.864 and 2.193 m/s), respectively, atconstant heat flux (120 W). The distribution of temperature along the channel wasphotographed using thermal camera and compared with images for the correspondingcontours which found numerically. The experimental results of heat transfer coefficientcompared with computational fluid dynamics model simulated by Ansys fluent 15.0. Agood agreement has been found between the experimental and numerical data, where thepercentage deviation between the experimental and the numerical results is (1% - 6% ). Theresults showed that, the local heat transfer coefficient increased by adding ribs, it alsoincreased as the velocity of the flow increased.

ENHANCEMENT THE HEAT TRANSFER FOR TWO-PHASE FLOW THROUGH A RECTANGULAR RIBBED VERTICAL CHANNEL

2018 ◽  
Vol 18 (1) ◽  
pp. 92-109
Author(s):  
Riyadh S Al-Turaihi ◽  
Doaa F Kareem
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Two Phase Flow ◽  
Vertical Channel ◽  
Numerical Data ◽  
Local Heat Transfer ◽  
Local Heat ◽  
Phase Flow ◽  
Two Phase

The heat transfer coefficient and temperature distribution of two phase flow (water, air)in rectangular ribbed vertical channel was investigated experimentally and numerically inthis work for different values of water and air superficial velocities (0.0421, 0.0842, 0.1158,0.1474 and 0.1684 m/s) and (1.0964, 1.425, 1.644, 1.864 and 2.193 m/s), respectively, atconstant heat flux (120 W). The distribution of temperature along the channel wasphotographed using thermal camera and compared with images for the correspondingcontours which found numerically. The experimental results of heat transfer coefficientcompared with computational fluid dynamics model simulated by Ansys fluent 15.0. Agood agreement has been found between the experimental and numerical data, where thepercentage deviation between the experimental and the numerical results is (1% - 6% ). Theresults showed that, the local heat transfer coefficient increased by adding ribs, it alsoincreased as the velocity of the flow increased.

Sign in / Sign up

Export Citation Format

Share Document