Open AccessIntensification of heat transfer in falling films on a bundle of horizontal tubes with microstructured surface
Author(s) -
O. A. Volodin,
Н. И. Печеркин,
А. Н. Павленко,
Н. Н. Зубков,
A. I. Kataev,
I. B. Mironova,
Mukunda P. Das
Publication year - 2020
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1677/1/012099
Subject(s) - materials science , heat transfer , falling (accident) , bundle , heat transfer coefficient , reynolds number , mechanics , evaporator , refrigerant , bar (unit) , surface (topology) , heat transfer enhancement , transverse plane , tube (container) , thermodynamics , composite material , geometry , physics , turbulence , meteorology , heat exchanger , medicine , environmental health , mathematics , structural engineering , engineering
Experimental results on measuring heat transfer in falling films of R21 refrigerant on a bundle of horizontal tubes with structured surfaces are presented. The experiments were carried out in the range of Reynolds number of the saturated liquid film from 500 to 1500 at a pressure of 3 bar in the evaporator. To intensify heat transfer, copper tubes with an external surface treated by the method of deformational cutting (MDC) were used. Three types of structures were used: structure No. 1 with half-closed microcavities, structure No. 2 with a rhomboid shape, and structure No. 3 created on the basis of structure No. 2 with additional transverse ribbing. It was shown that the studied types of structures can significantly increase the heat transfer coefficient as compared to a smooth surface. The structure with half-closed microcavities was the most effective for heat transfer enhancement.