Abstract: An object of the present invention is to minimize a volume of a hollow body by a combination of a horizontal H-letter shaped type gas-liquid separator and a plurality of plate-fin heat exchangers having a larger heat exchange performance per volume. In the present heat exchanging apparatus, fluid and refrigerants flow about in the hollow body through pipes while gas and liquid phases of the refrigerants are repeatedly separated and mixed for heat exchange between the fluid and the refrigerants. The apparatus comprises a plurality of plate-fin heat exchangers for exchanging heat between the refrigerants and the fluid, and a gas-liquid separator including upper and lower accommodation portions which are hollow cylinders laid in a horizontal direction both ends of which are airtightly sealed and an intermediate accommodation portion which connects the upper accommodation portion to the lower accommodation portion so as to form a sideways H-letter shape.

Abstract: According to the present invention there is provided a small-sized thermosiphon free from deterioration in its cooling efficiency caused by pressure loss of a refrigerant and in which a two-phase flow of a fluid to be cooled is sure to be distributed uniformly. The thermosiphon includes a cooling cylinder 1 having a plurality of independent refrigerant tanks 2 formed by partition walls 1c which are disposed between fluid inlet port 1a and outlet port 1b inside the cylinder, and a plate fin type heat exchanger 50 extending inside the cylinder through the partition walls 1c hermetically sealably. Under this construction, it is not necessary to use pipes for the circulation of refrigerant C between the refrigerant tanks 2 and refrigerant circulation paths 54 in the heat exchanger 50, thus preventing the deterioration of the cooling efficiency caused by pressure loss of the refrigerant.