Temperature Distribution of Rotary Heat Recovery Units

This paper deals with measurements of temperature distribution of rotary heat recovery units.A special grid of thermocouples has been made to measure air temperature in equallydistributed sampling points on each side of a heat recovery wheel. Air flow rates and theamount of recirculation air (leakage) were measured using a tracer gas. The results show thatthe temperature profile is generally dependent on both the rotational speed of the wheel andthe flow rate. Measurements also show that the placement of temperature sensors in the ductcan be significant, since wrong placements may lead to both faulty or non-optimized controlof the units, and wrong readings of the temperature efficiency. Propitious sensor placementshave been proposed.