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ISSN Online: 2377-424X

International Heat Transfer Conference 3
August, 7-12, 1966, Chicago, USA

UNSTEADY HEAT TRANSFER IN TUBES RESULTING FROM CHANGES IN HEAT FLOW, GAS MASS FLOW RATE AND ACOUSTIC RESONANCE

Get access (open in a dialog) DOI: 10.1615/IHTC3.1980
pages 57-70

Abstract

This paper is an attempt to review the results of the experimental research made into local heat transfer with the parameters varying periodically (Part 1) or aperiodically (Part II) in the turbulent air flow in an electrically heated tube. Part 1-the time-averaged heat transfer at pressure pulsations at an amplitude up to 0.25, frequency from 50 to 460 c./sec, pressure of (5÷20) · 10(5N/m2) and Reynolds numbers from 104 to 105. The paper shows that under resonance conditions heat transfer substantially (up to 2.3 times) varies with length in qualitative agreement with the value of kinetic energy pulsations in the standing wave. Part II-the unsteady heat transfer with variations in time of air flow rate and heat flow at Reynolds numbers from 2·104 to 3·105. The measured heat-transfer coefficient was found to depart from the quasisteady value (up to ±60 per cent). The experimental data of both parts of this paper are generalized by criterial relations.