Thermal performance testing of heat exchangers with reference to future automation

Abstract

The project was sponsored by an industrial company and was an investigation into reducing the time spent in thermal performance testing heat exchangers. Conventional testing requires establishing steady state conditions which is time consuming. The research considered two approaches - use of a non-steady state testing technique and closed-loop control of steady state testing. After reviewing and assessing existing non-steady state testing techniques the work starts to investigate a new dynamic testing method. In this method the objective was to develop a model of a heat exchanger from measurement of the inlet and outlet temperature responses following a temperature input disturbance. Then, to use the model in conjunction with only part of the transient response to predict the final steady state temperatures, thereby reducing testing time. Unfortunately, the time available limited the analysis to the first few steps in the development of the model and therefore the feasibility of dynamic testing has not been fully evaluated. The second aspect of the research is contained in an appendix and gives a preliminary assessment of automation of the steady state testing of heat exchangers. The report recommends that the sponsoring company should note the inconclusive investigation into one form of dynamic testing and consider closed-loop control as an alternative to reduce testing time.