| 摘要 |
<p>Air being fed to a drying chamber 4 is pre-heated by the air leaving the chamber 4 in a heat exchanger 2 formed by an inlet duct 2 being adjacent to an outlet duct 7. Where they are adjacent the walls of the inlet duct 2 and the outlet duct 7 may have corrugations 8. The dryer, which may be a laundry tumble dryer, also comprises an impellor 5 and a heater 3. A heat pump 10 with it's condenser in the inlet duct 2 and it's evaporator in the outlet duct 6 may be included to assist the transfer of heat from the outlet air to the inlet air. The structure may be so arranged that the air pressure decreases as it passes through the condenser or increases where an increase in the temperature is required.</p> |
