진동형 히트파이프를 이용한 의류 건조기 배기열 회수 장치에 관한 연구

Abstract

Currently, Usage of clothes dryers is increasing in worldwide because of reduction of sunshine and the busy life of modern people. In the United States, already in 2009, 80% of households use a clothes dryer. In the case of Korea, penetration rate has shown a growth rate of 2% per year and 10% of households use a clothes dryer. So high-efficiency clothes dryer is required. The biggest of energy loss in clothes dryer is heat of exhausted air after drying and it is 57% in total heat loss. It is useful to recover waste heat of exhausted air. In this study, we use pulsating heat pipe (PHP) for exhaust heat recovery system (EHRS) of clothes dryer to reduce energy consumption for air pre-heating before heat source. Flat tube heat exchangers is used to PHP for EHRS of clothes dryer. and one of them is no fin in evaporator section in order to prevent contamination from condensate and lint of laundry. R-134a was used as working fluid Three experiment was performed in this study. first experiment is to search for optimum charging ratio of working fluid in PHP with no fin in evaporator section. In experiment result, optimum charging ratio of working fluid is 40% of the total volume. Second experiment is performance of PHP according to presence of the fin in evaporator section. Performance of PHP with all fin is higher than performance of PHP with no fin. And in the titration of fin pitch, it is possible to avoid to condensate and lint problem. Lastly, third experiment is an experiment of PHP according to the number of inner flow channel of flat tube heat exchanger. In this experiment, performance of PHP was evaluated in difference of hydraulic diameters in same size of flat tube heat exchanger. One of the flat tube heat exchanger has 25 channels and hydraulic diameter is 1.02 mm. The other has 32 channels and hydraulic diameter is 0.84 mm. PHP of 25 channels with a large hydraulic diameter's performance was better than PHP of 32 channels's Considering these results, It is possible to recovery and re-used the exhausted heat of clothes dryer using PHP.