Degree of superheat, convection, heat transfer coefficient, vertical tube, measurement and instrumentation
An experimental study is performed to investigate condensation of superheated R134a inside a vertical tube. Experimental tests have been performed at the normal operating conditions found in a small power vapor compression refrigeration system. The experimental setup is described and the experimental procedure and data reduction method are explained. Experimental results of the condensation heat transfer coefficient are reported and discussed for different pressures, vapor mass flow rates and vapor degrees of superheating. The experimental heat transfer coefficients are also compared with those obtained using different correlations; it is found that the values are well predicted with the heat transfer correlations for wavy laminar and turbulent flow for gravity-controlled condensation.