Performance analysis of a novel frost-free air-source heat pump with integrated membrane-based liquid desiccant dehumidification and humidification

Abstract A novel frost-free air source heat pump (ASHP) combined with membrane-based liquid desiccant dehumidification and humidification is proposed and investigated in this paper. Liquid-to-air membrane dehumidifier (LAMD) is employed to dehumidify the air before entering the outdoor coils in the proposed system so that frosting can be prevented. Diluted solution is regenerated to humidify the supply air via the liquid-to-air membrane regenerator (LAMR), which can overcome the droplets carry-over problem in the liquid-to-air energy exchanger. Model simulations are carried out to study the system performance under various operating parameters and climatic conditions, meanwhile the comparison between the proposed system and conventional defrosting system is performed. Results demonstrate that the COP sen and the COP tot of the novel system are at least 37.7% and 64.3% higher than that of the COP reverse of conventional reverse-cycle defrosting ASHP system in the variation ranges of the analyzed parameters,respectively.Humidification effects on the supply air depend on the ambient air properties. And air humidification by the regenerator can meet the needs of the air-conditioning room comfort when the ambient air is above 0 °C and 70% RH.

[1]  Sm Deng,et al.  Developing a new frosting map to guide defrosting control for air-source heat pump units , 2015 .

[2]  Nicolas Kelly,et al.  Analysis of retrofit air source heat pump performance: Results from detailed simulations and compari , 2011 .

[3]  Li Zhang,et al.  Theoretical study on a frost-free household refrigerator-freezer , 2016 .

[4]  Xian-min Guo,et al.  Dynamic defrosting characteristics of air source heat pump and effects of outdoor air parameters on defrost cycle performance , 2009 .

[5]  Wenjin Wang,et al.  Performances of air source heat pump system for a kind of mal-defrost phenomenon appearing in moderate climate conditions , 2013 .

[6]  Ning Zhang,et al.  A heat pump driven and hollow fiber membrane-based liquid desiccant air dehumidification system: A transient performance study , 2016 .

[7]  Carey J. Simonson,et al.  A review of frosting in air-to-air energy exchangers , 2014 .

[8]  Li Zhang,et al.  Combination of air-source heat pumps with liquid desiccant dehumidification of air , 2012 .

[9]  Xiaosong Zhang,et al.  Effects of surface characteristic on frosting and defrosting behaviors of fin-tube heat exchangers , 2015 .

[10]  Fernando Testoni Knabben,et al.  An experimental study on defrost heaters applied to frost-free household refrigerators , 2013 .

[11]  Carey J. Simonson,et al.  Performance analysis of a membrane liquid desiccant air-conditioning system , 2013 .

[12]  Hans Martin Mathisen,et al.  A theoretical model to predict frosting limits in cross-flow air-to-air flat plate heat/energy exchangers , 2016 .

[13]  Chaobin Dang,et al.  Performance analysis of a no-frost hybrid air conditioning system with integrated liquid desiccant dehumidification , 2010 .

[14]  Yu Tian,et al.  Defrosting performances of a multi-split air source heat pump with phase change thermal storage , 2015 .

[15]  Jesper Kragh,et al.  New counter flow heat exchanger designed for ventilation systems in cold climates , 2007 .

[16]  Li-Zhi Zhang.  Coupled heat and mass transfer in an application-scale cross-flow hollow fiber membrane module for air humidification , 2012 .

[17]  Kwan-Soo Lee,et al.  Frosting and defrosting characteristics of surface-treated louvered-fin heat exchangers: Effects of fin pitch and experimental conditions , 2013 .

[18]  Li-Zhi Zhang,et al.  A heat pump driven and hollow fiber membrane-based liquid desiccant air dehumidification system: Modeling and experimental validation , 2014 .

[19]  Feng Cao,et al.  Hot gas defrosting method for air-source transcritical CO2 heat pump systems , 2015 .

[20]  Li-Zhi Zhang,et al.  Coupled heat and mass transfer in a counter flow hollow fiber membrane module for air humidification , 2011 .

[21]  Zhang Lin,et al.  Experimental analysis on a novel frost-free air-source heat pump water heater system , 2014 .

[22]  Li Zhang,et al.  A new method for preventing air-source heat pump water heaters from frosting , 2012 .

[23]  Tang Liming,et al.  Analysis on performance of a novel frost-free air-source heat pump system , 2011 .

[24]  Minglu Qu,et al.  A study of the reverse cycle defrosting performance on a multi-circuit outdoor coil unit in an air source heat pump – Part I: Experiments , 2012 .

[25]  Fu-Yun Zhao,et al.  Dynamic simulation of air-source heat pump during hot-gas defrost , 2003 .

[26]  Zhang Lin,et al.  Performance investigation of a novel frost-free air-source heat pump water heater combined with energy storage and dehumidification , 2015 .

[27]  Wei Su,et al.  Thermodynamic analysis of a compression-absorption refrigeration air-conditioning system coupled with liquid desiccant dehumidification , 2017 .

[28]  Shiming Deng,et al.  A modeling study on alleviating uneven defrosting for a vertical three-circuit outdoor coil in an air source heat pump unit during reverse cycle defrosting , 2016 .

[29]  Ling Yan,et al.  Experimental study on concentration change of spray solution used for a novel non-frosting air source heat pump system , 2014 .

[30]  Manuel R. Conde,et al.  Properties of aqueous solutions of lithium and calcium chlorides: formulations for use in air conditioning equipment design , 2004 .

[31]  Shiming Deng,et al.  A study on the performance of the airside heat exchanger under frosting in an air source heat pump water heater/chiller unit , 2004 .

[32]  Alan S. Fung,et al.  Experimental study and analysis of an energy recovery ventilator and the impacts of defrost cycle , 2015 .

[33]  Xiaosong Zhang,et al.  Preliminary study of a novel defrosting method for air source heat pumps based on superhydrophobic fin , 2015 .

[34]  Carey J. Simonson,et al.  State-of-the-art in liquid desiccant air conditioning equipment and systems , 2016 .

[35]  Carey J. Simonson,et al.  Expected energy and economic benefits, and environmental impacts for liquid-to-air membrane energy exchangers (LAMEEs) in HVAC systems: A review , 2014 .