Experimental analysis of the pressure characteristic curve of a forced convection boiling flow in single horizontal channel

Forced convection boiling flow, often referred to as two-phase flow, is a common phenomenon which occurs in many industrial processes. The relationship between the total pressure drop in a channel containing two-phase flow and the mass flux of the flow is known as the pressure characteristic curve....

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Bibliographic Details
Main Author: Doder, Dejan
Format: Others
Language:English
Published: Norges Teknisk-Naturvitenskaplige Universitet, 2013
Online Access:http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-20917
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Summary:Forced convection boiling flow, often referred to as two-phase flow, is a common phenomenon which occurs in many industrial processes. The relationship between the total pressure drop in a channel containing two-phase flow and the mass flux of the flow is known as the pressure characteristic curve. If any part of pressure characteristic curve contains a negative slope, flow instabilities might occur in the channel. Flow instabilities are unwanted because they can reduce the efficiency of the industrial process. In this study experimental work has been done to analyze the behavior of the pressure characteristic curve in two-phase flow by applying a sensitivity analysis. The parameters which were analyzed in the sensitivity analysis were inlet pressure, subcooling temperature, total heating power and heating power distribution. Also, experimental results from this study were compared with the results from a numerical study of the characteristic pressure curve of two-phase flow [1].The experimental study showed that all the analyzed parameters influence the behavior of the pressure characteristics curve. The comparison with the numerical study showed the same trends for behavior for the pressure characteristic curve for all analyzed parameters except for the total heating power.From the analyzed parameters it was shown that the inlet pressure has the largest relative influence on the behavior of the pressure characteristic curve compared to the other parameters. Lowering the inlet pressure leads to the largest change in the mass flux range where flow instabilities can occur. Lowering the inlet pressure also leads to the largest change in the negative slope the pressure characteristic curve.