Ukraine, Kyiv, National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute";
^*V. Ye. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine.

The modern development of electronics is associated with the problem of reducing the mass and size of the equipment while increasing its power. This leads to an increase in the temperature of both individual elements and the device as a whole, which contributes to a decrease in equipment reliability. This makes the development of inexpensive yet efficient cooling systems an urgent task. One of the ways to solve this problem is to use heat pipes of a new simplified design in cooling systems. This article compares the thermal characteristics of a cylindrical copper gravity heat pipe with a threaded evaporator before and after flattening. The working fluid used in the experiment was R141b. Experimental studies were conducted at two tilt angles relative to the horizontal under the conditions of forced convection cooling of the condensation zone. The influence of the change in the shape of the body from cylindrical to flat on the temperature in the heating zone of the heat pipe, thermal resistance, and heat transfer coefficients in the evaporation and condensation zones was shown in the range of heat power from 5 to 70 W. The choice of the heat pipe is justified based on the maximum thermal loads of electronic components and the orientation of the cooling system in space. Changing the shape of heat pipe from cylindrical to flat leads to a decrease in the maximum thermal power transmitted, but a flat heat pipe shape is more technologically feasible for use in cooling systems of electronic equipment.

Keywords: heat pipe, heat transfer characteristics, threaded evaporator, HP housing shape.

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