Peculiarities of thermal calculation of cross-flow plate air recuperators

Abstract

Abstract Application of modern energy-saving technologies is the most important task in development of construction industry. In the conditions of exhausting decrease of energy consumption of public, administrative buildings due to reduction of transmission heat losses the implementation of mechanical ventilation with recuperation of exhaust air heat becomes a rational way to increase energy efficiency. One of the key problems in the study of plate-type air recuperators is to find the temperature efficiency of the device. The value of this characteristic is influenced by such parameters as the area of the branched heat exchange surface, initial temperatures of heat carriers, volume flow rates, flow rate ratio, type of fins, etc. The purpose of the study is to compare coefficients of thermal efficiency of outside air as a function of Reynolds number obtained by engineering calculation, mathematical modelling and manufacturer’s data for the recuperator ISIS Recover HR-A-05-V-G4-E-1-60. The article substantiates the calculation method using the existing algebraic dependence describing heat transfer in the cross-flow scheme of coolant motion on the basis of new results. An empirical dependence is obtained, which adequately describes the results of numerical simulation using the ANSYS Fluent solver and engineering calculation.