A discussion about the methodology for validating a model of a finned-tube condenser considering different correlations for the heat transfer coefficients and pressure drop

Abstract

The selection of suitable correlations for calculating heat transfer coefficients and pressure drop plays a fundamental role in the use of semi-empirical models for the simulation of the performance of a heat exchanger. Therefore, a discussion about the best way for validating a condenser model and choosing the best set of correlations for both the heat transfer coefficients and pressure drop is presented. The studies were performed for both the air and refrigerant side in a round tube and plate fin condenser. A test campaign was specially designed to cover a wide range of key parameters, such as air velocity, condensation temperature, refrigerant mass flow rate, and condenser subcooling. The options for defining the boundary conditions in the model and the accuracy metrics are discussed in detail, allowing the identification of the most suitable correlations. By using this set of correlations, the prediction error is within an error band of ±0.4°C for the condensation temperature and ±0.6% in terms of capacity.