Liquid evaporation cooling apparatus

A liquid evaporation cooling apparatus comprising:

• an evaporator for boiling and evaporating an evaporable liquid under a lower pressure than a pressure of the air;
• a condenser for condensing vapor generated in the evaporator by a cooling evaporable liquid;
• an indirect heat exchanger installed at a load side;
• a cooling heat exchanger using the air as a cooling source;
• a circulation means for circulating an evaporable liquid in the evaporator to the indirect heat exchanger;
• and a cooling circulation means for circulating a cooling evaporable liquid in the condenser to the cooling heat exchanger, and further comprising a vapor compressor in a vapor duct extending from the evaporator to the condenser, wherein
• the vapor duct is provided with a bypass vapor path for bypassing the vapor compressor, and the bypass vapor path is provided with an on-off valve, such that the vapor compressor is shut down and the on-off valve is opened when a temperature at the condenser side becomes lower than a temperature at the evaporator side, wherein
• the cooling circulation means is provided with a bypass circulation line for bypassing the cooling heat exchanger, the bypass circulation line is provided with a control valve that is opened when a temperature at the condenser side becomes lower than a temperature in the evaporator, and opening of the control valve is controlled in accordance with a temperature at the condenser side or a temperature at the evaporator side such that a degree of the opening becomes larger with a drop in the temperature and becomes smaller with a rise in the temperature.