Heat recovery in air conditioning systems - with heat exchanger using latent heat of water vapour in stale air

摘要

Heat exchanger for transfer of heat between two gas streams, both at approx. the same pressure and both at temps. within about 20 degrees C of ambient, the warmer stream being moist and the cooler stream being comparatively dry. The warmer stream and the cooler stream flow in passages on opposite faces of a partition material which is permeable to water vapour carried in the warmer stream. Suitable partition materials include wood, cardboard, paper, textile cloth or a plastic membrane. Provides heat transfer between two gas streams within limited pressure and temp. ranges, partic. for recuperative heat exchange in air-conditioning systems by using heat from outgoing stale air to warm up incoming, cooker, fresh air. Very high thermal efficiency, i.e. heat transfer coefficient, results from substantially full enthalpy, transfer via the permeable partition. Advantage is taken of both latent and sensible heat in the warmer stream. The construction is simple, inexpensive and requires negligible maintenance.