Combining Microstructured Surface and Mesh Covering for Heat Transfer Enhancement in Falling Films of Refrigerant Mixture

The article presents the experimental results of combining a basic microstructure with partly closed pores and mesh covering for heat transfer enhancement at film flow refrigerant mixture. To reveal effect combined structure, on microstructured surface without as well smooth only has been studied. All series were carried out using binary mixture R114 R21 refrigerants. flowed down outer vertical cylinder in undeveloped turbulence regime, when Reynolds number varied from 400 to 1300. It is shown that fin pitch 200 μm, height 220 longitudinal knurling 160 created by deformational cutting, demonstrates significant enhancement: up four times compared surface. However, adding an aperture μm wire diameter 100 reduces intensification. overlaid also does not provide itself. absence or even deterioration surfaces can be primarily associated low thermal conductivity material shortcomings applied method mounting. possibility deteriorating vapor removal due incorrect selection parameters was analyzed. coefficient values obtained dependencies available literature predicting pool boiling microfinned surfaces.