Comparative study of heat transfer and pressure drop during flow boiling and flow condensation in minichannels

Archives of Thermodynamics

Blanka JakubowskaGda?sk University of Technology, Faculty of Mechanical Engineering, Narutowicza 11/12, 80-233 Gda?sk, PolandOther articles by this author:De Gruyter OnlineGoogle Scholar¹  Dariusz MikielewiczCorresponding authorGda?sk University of Technology, Faculty of Mechanical Engineering, Narutowicza 11/12, 80-233 Gda?sk, PolandEmailOther articles by this author:De Gruyter OnlineGoogle Scholar¹  Rafa? AndrzejczykGda?sk University of Technology, Faculty of Mechanical Engineering, Narutowicza 11/12, 80-233 Gda?sk, PolandOther articles by this author:De Gruyter OnlineGoogle Scholar¹  Jaros?aw MikielewiczThe Szewalski Institute of Fluid-Flow Machinery Polish Academy of Sciences, Fiszera 14, 80-231 Gda?sk, PolandOther articles by this author:De Gruyter OnlineGoogle Scholar² 

[1]Gda?sk University of Technology, Faculty of Mechanical Engineering, Narutowicza 11/12, 80-233 Gda?sk, Poland

[2]The Szewalski Institute of Fluid-Flow Machinery Polish Academy of Sciences, Fiszera 14, 80-231 Gda?sk, Poland

关键词: Keywords: Two-phase pressure drops;    Heat transfer coefficient;    Boiling;    Condensation;   

DOI  :  10.2478/aoter-2014-0019

学科分类：能源（综合）

来源: Polska Akademia Nauk * Oddzial w Gdansku, Instytut Maszyn Przeplywowych / Polish Academy of Sciences, Institute of Fluid-Flow Machinery

【 摘 要 】

In the paper a method developed earlier by authors is applied to calculations of pressure drop and heat transfer coefficient for flow boiling and also flow condensation for some recent data collected from literature for such fluids as R404a, R600a, R290, R32,R134a, R1234yf and other. The modification of interface shear stresses between flow boiling and flow condensation in annular flow structure are considered through incorporation of the so called blowing parameter. The shear stress between vapor phase and liquid phase is generally a function of nonisothermal effects. The mechanism of modification of shear stresses at the vapor-liquid interface has been presented in detail. In case of annular flow it contributes to thickening and thinning of the liquid film, which corresponds to condensation and boiling respectively. There is also a different influence of heat flux on the modification of shear stress in the bubbly flow structure, where it affects bubble nucleation. In that case the effect of applied heat flux is considered. As a result a modified form of the two-phase flow multiplier is obtained, in which the nonadiabatic effect is clearly pronounced.

【 授权许可】

Unknown