An experimental study of frost distribution and growth on finned tube heat exchangers used in air source heat pump units

2018 ◽  
Vol 132 ◽  
pp. 38-51 ◽  
Author(s):  
Long Zhang ◽  
Yiqiang Jiang ◽  
Jiankai Dong ◽  
Yang Yao ◽  
Shiming Deng
2017 ◽  
Vol 110 ◽  
pp. 835-843 ◽  
Author(s):  
Minglu Qu ◽  
Yanan Fan ◽  
Jianbo Chen ◽  
Tianrui Li ◽  
Zhao Li ◽  
...  

Author(s):  
P. Mawasha ◽  
S. P. Rooke ◽  
R. Gross

Abstract Performance map-based modeling has been commonly employed for the rapid prediction of air conditioning and heat pump steady state performance. This approach requires that performance characteristics of the compressor and heat exchangers can be expressed in the form of simple algebraic functions. The growth of microprocessor based control, particularly in residential systems, has led to more frequent off-design operation. This study explores the ability of the map-based modeling approach to predict off-design operating performance of a single air-source heat pump operating in the cooling mode. Off-design conditions were simulated by varying the evaporator air flow rate over a wide range. Performance predictions are compared with the predictions of a more rigorous heat pump simulation program which utilizes heat transfer correlations for the heat exchangers rather than performance maps. A PC math package was used to generate results for the map-based model, while a Fortran compiler was used to generate results for the more rigorous model. The benefits of the map-based approach in predicting system performance are presented and discussed.


2021 ◽  
pp. 111695
Author(s):  
Xiaoxia Bai ◽  
Shengnan Liu ◽  
Shiming Deng ◽  
Long Zhang ◽  
Minchen Wei

2020 ◽  
Vol 25 (3) ◽  
pp. 9-16
Author(s):  
Gwon-Seok Sun

Frosting on the surface of a heat exchanger degrades its cooling efficiency in a cooling system. In this study, frost flow analysis is performed for frost reduction. A new type of air blast refrigerator is designed for reducing frost formation in its finned tube. Experimental results of the frost formation in the air blast refrigerator are presented. The main difference between the proposed and conventional air blast refrigerators is the flow of air through the finned tube. The proposed refrigerator produces less frost than the conventional refrigerators.


Energies ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1274 ◽  
Author(s):  
Arif Widiatmojo ◽  
Sasimook Chokchai ◽  
Isao Takashima ◽  
Yohei Uchida ◽  
Kasumi Yasukawa ◽  
...  

The cooling of spaces in tropical regions, such as Southeast Asia, consumes a lot of energy. Additionally, rapid population and economic growth are resulting in an increasing demand for space cooling. The ground-source heat pump has been proven a reliable, cost-effective, safe, and environmentally-friendly alternative for cooling and heating spaces in various countries. In tropical countries, the presumption that the ground-source heat pump may not provide better thermal performance than the normal air-source heat pump arises because the difference between ground and atmospheric temperatures is essentially low. This paper reports the potential use of a ground-source heat pump with horizontal heat exchangers in a tropical country—Thailand. Daily operational data of two ground-source heat pumps and an air-source heat pump during a two-month operation are analyzed and compared. Life cycle cost analysis and CO2 emission estimation are adopted to evaluate the economic value of ground-source heat pump investment and potential CO2 reduction through the use of ground-source heat pumps, in comparison with the case for air-source heat pumps. It was found that the ground-source heat pumps consume 17.1% and 18.4% less electricity than the air-source heat pump during this period. Local production of heat pumps and heat exchangers, as well as rapid regional economic growth, can be positive factors for future ground-source heat pump application, not only in Thailand but also southeast Asian countries.


2010 ◽  
Vol 30 (8-9) ◽  
pp. 892-899 ◽  
Author(s):  
Cai-Hua Liang ◽  
Xiao-Song Zhang ◽  
Xiu-Wei Li ◽  
Zhen-Qian Chen

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