| 摘要 |
1,254,068. Automatic temperature control systems. DUNLOP HOLDINGS Ltd. March 14, 1969 [March 20, 1968], No. 13432/69. Heading G3R. A method of controlling the temperature of a gas stream flowing in a chamber comprises injecting into the stream a low boiling point liquid which vapourizes and absorbs heat from the gas, measuring the temperature of the gas and regulating the supply and absorption of heat to achieve the required temperature. Preferably the gas stream is recirculated continuously and at times the heat supply or absorption may be cut off completely. The liquid may be mechanically atomized after injection or may be atomized electrostatically. The liquid may be liquid nitrogen having a boiling point of -196‹ C. A chamber is formed by a core 2 surrounded by a box like structure 1 containing a fan 7 operating in a throat 9, 10 with a conduit 12 discharging the liquid through a nozzle 13 into the fan blades to mechanically atomize the liquid. Current to a plurality of heaters 14 is controlled by a platinum resistance thermometer 21 disposed in a test chamber 5 which may house, for example, an apparatus for testing torsion of materials. An inert gas may be introduced into the chamber and the heating may be performed by the injection of preheated gas. The heaters 14 should preferably have a low heat capacity thus giving a rapid supply of heat to the gas stream. |
