Heating fresh air by hot exhaust air of HVAC systems

摘要

The present work concerns heating fresh air by the hot exhaust air of all–air heating ventilating and air conditioning HVAC systems. To proceed, a prototype is implemented and a parametric analysis is carried out to test the effect of temperatures and mass flow rates on the performance of the heat recovery system. Experiments are performed under typical conditions simulating the HVAC operation in cold climates. On the other hand, a generalized procedure of calculation is suggested based on the experimental results. It allows to simulate heat recovery designs and to perform parametric study without need to perform new experimental studies. It was shown that powers up to 110W can be economized in cold climates and for low air flow rates of around 0.1kg/s and 0.005kg/s for respectively the hot exhaust air and the fresh cold air. Extrapolation shows that economized power can exceed 1kW for a room of heating load 4kW if all of the supply air is exhausted.