Results 171 to 180 of about 60,972 (209)

A numerical investigation of convective condensation in micro-fin tubes of different geometries

Numerical Heat Transfer, Part A: Applications, 2020
A numerical investigation was conducted to determine the effects of fin shape on heat transfer coefficients during in-tube condensation of R410A.
Weiyu Tang, Wei Li, W. J. Minkowycz
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Modeling of condensation heat transfer of refrigerant mixture in micro-fin tubes

International Journal of Heat and Mass Transfer, 2006
This paper presents a new refrigerant-mixture model for condensation in micro-fin tubes. The new refrigerant-mixture model is developed based on a theoretical analysis of turbulent film condensation inside smooth tubes. Several modifications have been implemented in the original smooth-tube model to account for mass transfer thermal resistance between ...
Louay M. Chamra, Pedro J. Mago
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Nucleate pool boiling of R-134a on plain and micro-finned tubes

International Journal of Refrigeration, 2013
This paper presents experimental results for the nucleate pool boiling of R134-a on plain and micro-finned tubes at pressures between 6.1 bar and 12.2 bar. Local measurements of the temperature enabled us to identify the physical mechanism responsible for the enhancement of the heat transfer due to the micro-fins.
Sérgio Pereira Rocha, Olivier Kannengieser, Elaine Maria Cardoso, Júlio César Passos   +3 more
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A generalized correlation for evaporation heat transfer of refrigerants in micro-fin tubes

International Journal of Heat and Mass Transfer, 2002
A generalized correlation for flow boiling heat transfer in horizontal micro-fin tubes was developed by implementing non-dimensional parameters accounting for heat transfer enhancement over smooth tubes and physical phenomena into the basic form of a smooth tube correlation.
Rin Yun, Yongchan Kim, Kookjeong Seo, Ho Young Kim   +3 more
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Modeling of condensation heat transfer of pure refrigerants in micro-fin tubes

International Journal of Heat and Mass Transfer, 2005
Abstract A new semi-empirical condensation model for heat transfer coefficient of pure refrigerants flowing inside micro-fin tubes is presented. The new model is developed based on a theoretical analysis of turbulent film condensation inside smooth tubes. Several modifications have been implemented in the original smooth-tube model to account for the
Louay M. Chamra, Pedro J. Mago, Meng-Onn Tan, Chea-Chun Kung   +3 more
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Single-phase heat transfer and flow characteristics of micro-fin tubes

Applied Thermal Engineering, 2005
Abstract Single-phase heat transfer and flow characteristics of micro-fin tubes were investigated experimentally. Four different tubes were used to obtain experimental heat transfer coefficients and friction factor with varying Re (3000–40,000) and Pr (4–7). The Re affected the friction factor in the fully turbulent region for test tubes.
Dong Hyouck Han, Kyu-Jung Lee
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Prediction of Condensation and Evaporation in Micro-Fin and Micro-Channel Tubes

1999
This paper surveys methods to predict condensation and evaporation in plain, and in micro-fin and micro-channel tubes. Hydraulic diameters as small as 1.0 mm are of interest. To date, the Shah correlation has been well accepted for prediction of condensation in plain tubes. This work shows apparent deficiencies of the Shah equation for p/pCT > 0.44. An
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Evaporation of R407C/oil mixtures inside corrugated and micro-fin tubes

Applied Thermal Engineering, 2007
Abstract The paper reviews the evaporation of R407C data currently available in the literature. The experimental rig and procedure are discussed. Experimental data about the evaporation for the pure R407C and R407C/oil mixtures in two smooth tubes and two enhanced tubes are also presented. The performance benefits of the micro-fin tube and corrugated
Waldemar Targanski, Janusz T. Cieslinski
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Experimental Study of Annular and Stratified Flows in Horizontal Micro-Fin Tubes

ASME 4th International Conference on Nanochannels, Microchannels, and Minichannels, Parts A and B, 2006
In this paper, a new kind of evaporative heat transfer experiment for the cooling process of coolers/condensers is conducted. The design of the test coils is immersed in an air-water bubbling layer. The air-water two-phase flow passes through the tubes of the coils.
Q. Chen, R. S. Amano
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Development of a test apparatus for micro-finned tube used in air-conditioners

2012 IEEE International Conference on Computer Science and Automation Engineering (CSAE), 2012
Micro-finned tubes are widely used in air-conditioners to improve the performance. A test apparatus for their heat transfer characteristics is helpful for the development of new finned tube. In this paper such an apparatus was set up to carry out evaporation and condensation test. The refrigerant used was R410A.
Zhang Shaozhi, Shi Mingyao, Chen Qi, Chen Guangming   +3 more
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