Аnаlysis of efficiency of using heаt pump units for heаt recovery from ventilаtion emissions

Abstract

The system analysis of the current state of quality of functioning of ventilation systems of industrial and public buildings in terms of volumes and modes of fuel and energy resources consumption has been carried out. The analysis of energy efficiency of using a steam-compression heat pump system for utilization of heat of ventilation emissions for heating the supply air has been carried out. Direct-flow ventilation systems with and without the heat pump unit are compared. A mathematical model and a calculation algorithm of the considered ventilation systems are offered. The model can calculate operation modes of one of the arrangement options both with fixed values of parameters affecting the result and with variables, which allows carrying out multivariate calculations and numerical research quickly and with minimum labour inputs. The results of comparative analysis are given on the example of a specific production room. Heat, moisture and air balance data obtained from regulatory documents and reference data, as well as the results of research by other authors are used as source data. Depending on the chosen arrangement, the contents of the calculations and the results obtained are different.In addition, the developed model allows, depending on the considered arrangement and the need, to obtain a large number of output parameters, such as surface areas of heat exchangers, heat transfer coefficients, all thermophysical properties of working media in all nodal points of the flowing process, etc. The principles of a comprehensive approach to assessing the efficiency of ventilation systems based on a system analysis, taking into account the parameters of heat and cold consumers, environmental parameters, the impact of aerodynamic characteristics of the air duct on energy costs and the tariff index in different climatic zones of Russia are substantiated.