Film Condensation in Horizontal Microchannels: Effect of Channel Shape

Wang, Huasheng; Rose, John

doi:10.1115/icmm2005-75260

Cited by 25 publications

(19 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For the steam flow condensation in tube, as well as the two-phase flow regime map, many investigations have been carried out, scholars have proposed many theoretical models about the steam flow condensation in tube, including VOF [20], Level set [21] and the interface tracking method [22][23][24][25][26][27][28]. Both VOF and the Level set model are based on the number of grids, so as a result, one can hardly obtain an accurate result when the film is thin enough.…”

Section: Condensate Film Development Inside Finned Flat Tubementioning

confidence: 99%

“…Both VOF and the Level set model are based on the number of grids, so as a result, one can hardly obtain an accurate result when the film is thin enough. In the view of interface tracking method, Wang et al [22][23][24] utilized the integral method and obtained the condensate film development equation to predict film condensation in micro-channels. Fiedler et al [25][26][27][28] presented a study of stratified flow pattern for laminar reflux condensation of a pure saturated vapor in an inclined small diameter circular tube.…”

Section: Condensate Film Development Inside Finned Flat Tubementioning

confidence: 99%

See 1 more Smart Citation

Anti-Freezing Mechanism Analysis of a Finned Flat Tube in an Air-Cooled Condenser

Guo

Cheng

et al. 2017

Energies

View full text Add to dashboard Cite

Abstract:In cold winter weather, the air-cooled condensers (ACCs) face serious freezing risks, especially with part load of the power generating unit. Therefore, it is of benefit to investigate the heat transfer process between the turbine exhaust steam and cooling air, by which the freezing mechanism of the finned tube bundles can be revealed. In this work, the flow and heat transfer models of the cooling air coupling with the circulating water, are developed and numerically simulated for the anti-freezing analysis on basis of the finned tube bundles of the condenser cell. The local air-side heat transfer coefficient, condensate film development, and non-condensable gas development are obtained and analyzed in detail. The results show that, the most freezing risk happens at the fin base due to the highest air-side cooling capacity, besides the windward velocity, ambient temperature and turbine back pressure all determine the freezing risk with the constant inlet flow rate of the non-condensable gas. Furthermore, increasing fin thickness and decreasing fan rotating speed are the most effective anti-freezing measures. Additionally, increasing turbine back pressure can also be adopted to avoid ACC freezing, however the adjustment of outlet steam-air flow is not recommended.

show abstract

Section: Condensate Film Development Inside Finned Flat Tubementioning

confidence: 99%

Section: Condensate Film Development Inside Finned Flat Tubementioning

confidence: 99%

Anti-Freezing Mechanism Analysis of a Finned Flat Tube in an Air-Cooled Condenser

Guo

Cheng

et al. 2017

Energies

View full text Add to dashboard Cite

show abstract

“…Wang and Rose [41] presented a progress report on a theoretical study of film condensation in microchannels. Their model took account of surface tension, vapor shear stress and gravity.…”

Section: Literature Reviewmentioning

confidence: 99%

A Critical Review on Condensation Heat Transfer in Microchannels and Minichannels

Awad

Dalkılıç

Wongwises

2014

Journal of Nanotechnology in Engineering and Medicine

View full text Add to dashboard Cite

A C ritical R eview on C ondensation H eat T ran sfer in M icro ch an n els and M in ic h a n n e lsCondensation in microchannels and minichannels is widely used in small devices such as air-cooled condensers for the air-conditioning and automotive industry, in heat pipes, thermosyphons and other applications for system thermal control. Currently, many research centers all over the world are dealing with the structure and operation of com pact refrigerating devices. This is in line with the trend of 21st century that is moving towards the use of energy-saving and environmentally friendly technical equipment. In the present study, a critical review on condensation heat transfer in microchannels and minichannels is presented. This review include a wide range of different parameters such as the channel diameter (d), the saturation temperature (Ts), the mass flux (G), the vapor quality (x), different working fluids like steam, C02 or R744, FC72, R22, R410A, and R407C, various shapes such as circular and noncircular, different orientations like hori zontal and vertical, and systems consist o f either single or multiple channels. At the end, recommendations for future studies will be given. As a result, this paper cannot only be used as the starting point for the researcher interested in condensation heat transfer in microchannels and minichannels, but it also includes recommendations for future studies on condensation heat transfer in microchannels and minichannels.

show abstract

“…The problem has been approached from a purely theoretical point of view by Wang and Rose (2003, 2004 (31) - (35) . The treatment uses the Nusselt (1916) (36) approximations for the condensate film on the channel walls and includes the surface tension generated pressure gradient at right angles to the flow direction as well as the effects of gravity and vapour shear stress on the surface of the film.…”

Section: Condensation In Microchannelsmentioning

confidence: 99%