ANALYSIS OF LOCAL EXERGY LOSSES IN HEAT CONDUCTION PROCESSES FOR AN AIR-HEATING HEAT EXCHANGER OF A BOILER PLANT

The work investigated local exergy losses associated with heat conduction processes for a plate air-heating heat exchanger. The heat recovery unit is part of the heat recovery system of the heating boiler, designed to heat the blast air. For the research, a complex technique developed at the ITTF NASU was used, combining exergy methods with methods of the theory of thermal conductivity. The patterns of changes in local exergy losses associated with heat conduction processes and boiler operating modes have been established. The areas of variation of the specified parameters are determined at which local exergy losses in the air-heating heat exchanger have the lowest values and, accordingly, the values of the exergy efficiency of the heat exchanger are the greatest. The indicated range of change in the thermal conductivity coefficient is 0.025 kW/mK — 0.04 kW/mK.