Experimental investigation on the defrosting performance of a finned-tube evaporator using intermittent ultrasonic vibration
Experimental investigation on the defrosting performance of a finned-tube evaporator using intermittent ultrasonic vibration
复制标题
间歇超声振动翅片管蒸发器除霜性能实验研究
DOI：
10.1016/j.apenergy.2015.08.072
复制
发表时间：
2015
期刊：
影响因子：
11.2
通讯作者：
Yao Wudong
中科院分区：
文献类型：
--
作者：
Tan Haihui;Xu Guanghua;Tao Tangfei;Sun Xiaoqi;Yao Wudong
空气源热泵在一定的环境条件下运行时，室外盘管的翅片表面会出现结霜现象。结霜会增加系统能耗，降低系统性能，因此需要定期对结霜进行处理。本文研究了一种利用间歇式超声振动的新方法。首先，测定了室外双排盘管的振动衰减特性和不同环境条件下的结霜特性。其次，使用MATLAB软件计算了施加和不施加间歇超声振动的平均霜层厚度。最后分析了该系统的节能效果、供热能力的提高和性能系数的提高。实验结果表明，间歇式超声振动能有效去除翅片表面的积霜，对于双排翅片管蒸发器，采用额定功率为50 W、谐振频率为40 kHz的超声换能器，单个超声换能器的有效振膜面积为0.165 m2。与未加超声振动的机组相比，加超声振动的机组的热泵能耗降低3.14-5.46%，制热量提高2.2-9.03%，COP提高6.51- 15.33%。此外，室内侧的热舒适性得到了明显改善。
When an air-source heat pump (ASHP) was operated in heating mode under certain ambient conditions, frost always accumulated on the fin surface of its outdoor coil. Frosting may increase the energy consumption and deteriorate the performance of the ASHP, and hence, periodic defrosting is necessary. In this study, a new defrosting method using intermittent ultrasonic vibration was investigated. First, the vibration attenuation characteristics of a double-row outdoor coil and the frost growth characteristics under different ambient conditions were determined. Next, the average frost thickness with and without the application of intermittent ultrasonic vibration was calculated using MATLAB software. Finally, the decrease in defrosting energy consumption, the increase in heating capacity, and the increase in the coefficient of performance were analysed. The experimental results indicate that intermittent ultrasonic vibration could effectively remove the frost accumulated on the fin surface, and the effective defrosting area of an single ultrasonic transducer was 0.165 m2for a double-row finned-tube evaporator on which an ultrasonic transducer with a rated power of 50 W and resonant frequency of 40 kHz was applied. The defrosting energy consumption of the ASHP unit with ultrasonic vibration was 3.14–5.46% lower than that without ultrasonic vibration, whereas the heating capacity increased by 2.2–9.03% and the COP increased by 6.51–15.33%. In addition, the thermal comfort of the indoor side was clearly improved.