Thermal performance of a polymeric pulsating heat pipe

Marco Antonio Covielo¹; Cristiano Bigonha Tibiriçá¹

¹ EESC-USP

doi:10.20906/CPS/COB-2015-0267

Resumo

The objective of this work was the investigation of the heat transfer characteristics of pulsating heat pipes built using polymeric flexible materials. An experimental apparatus to obtain heat transfer measurement in polymeric pulsating heat pipes was developed. The heat transfer rate transmitted by the pulsating heat pipe was calculated through energy balance in the evaporator, using measurements of temperature variations in the water outside the evaporator. The internal fluid used in the pulsating heat pipe was R134a and the internal diameter was 2.0 mm. Type K thermocouples were used for temperature measurements along the heat pipe and for the energy balance of water outside the evaporator. The total thermal resistance for the pulsating heat pipe was calculated based on the temperatures differences between the evaporator and condenser, and the exchanged heat rate. The effect of orientation of the heat pipe in respect to the gravity field was also evaluated. As results, heat transfer rates up to 36 W was obtained with total thermal resistances of 0.8 oC/W. The results showed the potential of applying flexible polymeric materials to build pulsating heat pipes which allows versatile heat exchanger design in applications with complex geometries.

Palavras-chave: heat pipes; pulsating; flexible; micro