EXPERIMENTAL INVESTIGATION OF CO_2 SINGLE PHASE FLOW IN A SINGLE HORIZONTAL MICRO-CHANNEL IN CONSTANT HEAT FLUX CONDITIONS

摘要

The use of carbon dioxide as alternative refrigerant in refrigeration plants and heat pumps has been focused recently. Through the specific properties of CO_2, the use of very compact heat exchangers is relevant and the technology of micro-channel heat exchangers rises as a suitable solution. The experimental investigation of CO_2 flow in a single micro-channel with an inner diameter of 500 μm is planned with an original test section. This test section will be dedicated for CO_2 two phase flow analysis further. The local heat transfer coefficient will be estimated with micro-thermocouples on the micro-channel wall. The pressure drop is also measured. First results in single phase pressure drop are presented in this paper and exhibit promising coming data in two phase flow pressure drop and heat transfer.