The influence of the components of the heat transfer coefficient on the efficiency of a low-power tubular heat exchanger
author:
EWA PELIŃSKA-OLKO, YESSICA BARNAŚ
ORCID ID:
0000-0002-9024-9111
No:
01/2021 Instal p. 25-30
DOI:
10.36119/15.2021.1.1
Co-flow and counter-flow (WW, WP) heat exchangers of low-power tube-in-tube in configuration 1,2 were tested.
Configuration 1 meant the flow of the warmer medium in the inner pipe and colder in the outer pipe, while configuration 2 – the cooler medium in the inner pipe, warmer in the outer pipe. Higher values of the experimental
heat transfer coefficient kl, both for WW and WP were observed in configuration 2. In this work, the experimental
values of kl were compared with the values calculated with the use of selected theoretical methods. The largest
number of theoretical values of kl, consistent with the experiment, for all tested types of exchangers and their
configurations, were obtained for the Hausen formula. The coefficient kl includes three components: the element
describing the heat transfer from the warmer working medium to the diaphragm, conduction through the diaphragm
separating both factors and the transfer of heat from the diaphragm to the cooler medium. The size of this coefficient
determines the capacity per 1 running meter of the tube exchanger and thus, together with the average temperature
difference of the working media, it affects the heat exchange surface and thus the dimensions of the entire
exchanger.
Keywords:
About Authors:
dr inż. Ewa Pelińska-Olko https://orcid.org/0000-0002-9024-9111 – Wydział Mechaniczno-Energetyczny, Politechnika Wrocławska, Wrocław, Polska; mgr inż. Yessica Barnaś – ZF Steering Systems Poland, Centrum inżynieryjne w Bielsku-Białej. Corresponding author: ewa.olko@pwr.edu.pl.