STUDIES ON THE VINYL-HOUSE HOUSE HEATING BY THE UNDERGROUND HEAT EXCHANGE SYSTEM

The application of the underground heat exchange system in Chinese protected Cultivation vegetable production for solar energy storage and heating in the vinyl-house has been studied. the result of the experiment showed that the underground heat exchange system can store solar energy and useit for heating in the vinyl-house during the night effectively. There fore, the difference of air temperature inside and outside the vinylhouse during the night can be maintained as much as 10℃ and at sametime the soil temperature in the vinyl-house can be raised accordingly. the microclimate conditions suitable for transplanting vegetables in the vinylhouse with underground heat exchange system is 20-30 days earlier than ordinary one in the spring time. After further improving and perfecting this system may make the transplanting date in the vinyl-house coming even earlier than one month. In addition, a model of the underground heat exchange system has been developed according to the experimental data.