| 摘要 |
PURPOSE:To automatically control the outlet temperature of cooling water positively, by detecting the average temperature on the surface of water in the cooling water pit of a water cooling tower, and by automatically changing the number of revolution of a cooling fan, based on the detected signals of the average temperature. CONSTITUTION:The air flow rate of a cooling fan is controlled by detecting the average temperature in the surface part of water in a cooling water pit, where the change in temperature in cooling water can be detected fastest by a temperature detecting means 14, and by putting the detected value into a temperature controller unit 11 as a feedback signal, and then by automatically changing the number of revolution of a cooling fan 3 in accordance with a deviation signal. By this means, the change in temperature in cooling water can be detected with little time lag being produced, even in the case of a cooling water system in which fluctuation in temperature and the flow rate of return water are large, and the temperature at the outlet of cooling water can be automatically controlled positively, by controlling the number of revolution of a cooling fan smoothly without producing the hunting action. |
