Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 555
Author(s):  
Sangkyung Na ◽  
Sanghun Song ◽  
Seunghyuk Lee ◽  
Jehwan Lee ◽  
Hyun Kim ◽  
...  

In this study, evaporator optimization, via both experimental and simulation methods was conducted. To evaluate the evaporator performance, under the optimal system, the compressor operating time and the effects of oil on the refrigerator system were studied. If the temperature of the refrigerator chamber reaches the setting value, the compressor stops working and it leads to the temperature of the refrigerator chamber slowly increasing, due to the heat transfer to the ambient. When the refrigerator temperature is out of the setting range, the compressor works again, and the refrigerator repeats this process until the end of its life. These on/off period can be controlled through the compressor piston movement. To determine the optimal compressor operating conditions, experiments of monthly power consumption were conducted under various compressor working times and the lowest power consumption conditions was determined when the compressor worked continuously. Lubricating oil, the refrigerator system, using oil, also influenced the system performance. To evaluate the effect of oil, oil eliminated and oil systems were compared based on cooling capacity and power consumption. The cooling capacity of the oil eliminated system was 2.6% higher and the power consumption was 3.6% lower than that of the oil system. After determining the optimal operating conditions of the refrigerator system, visualization experiments and simulations were conducted to decide the optimal evaporator and the conventional evaporator size can be reduced by approximately 2.9%.


2012 ◽  
Vol 443-444 ◽  
pp. 837-842
Author(s):  
Jiang Qi Long ◽  
Si Jia Zhou ◽  
Ping Yu

The reciprocating compressor contains crank-rod mechanism whose unbalanced inertia force mainly accounts for mechanical noise and vibration during the working process. Through the analysis of fit between the diameter of the compressor piston and the crank eccentricity, influence of imbalance force on the compressor vibration and noise is obtained under no change in other parts. The tests of vibration and noise are followed for the purpose of verification. The results show that the vibration and noise control will be better if a small piston diameter and a big crank eccentricity are utilized.


2021 ◽  
pp. 51-54
Author(s):  

A one-dimensional model for calculating the sliding bearing of a piston engine and compressor is proposed. The results of approximation of the graphs by analytical dependences of the relative eccentricity on the bearing load coefficient for different values of the ratio of the working length of the bearing to the diameter of the crankshaft journal are presented in the form of exponential functions. Keywords: sliding bearing, heat balance, piston compressor, piston engine, friction [email protected]; [email protected]; [email protected]


2006 ◽  
Vol 304-305 ◽  
pp. 29-32 ◽  
Author(s):  
Hang Gao ◽  
Y.G. Zheng ◽  
W.G. Liu ◽  
Jian Hui Li

Manufacturing of vitrified bond CBN wheels for internal precision grinding of the air-conditioner compressor piston hole is still big challenge to all of the domestic manufacturers. Recently, by choosing pre-melting mixed CBN abrasives and a proper sintering process, a cost-effective method was conceived to produce grinding wheels of comparative quality. The grinding performance of wheels was evaluated with a series of internal precision grinding of compressor piston hole. Experimental results show that the vitrified bond CBN grinding wheel produced by this method has better grinding performance, and can be substitute to the same type of grinding wheels imported. But the manufacturing cost is only 60% of the wheel imported according to estimation.


2012 ◽  
Vol 622-623 ◽  
pp. 1821-1825
Author(s):  
Khanittha Wongseedakaew

This paper presents the effect of squeeze motion to elastohydrodynamic lubrication (EHL) in piston pin of air compressor with non-Newtonian lubricants based on a Carreau viscosity model. The time dependent modified Reynolds equation and elasticity with initial conditions were formulated and solved numerically using a multigrid multilevel with full approximation technique for a piston pin. Effects of bearing materials and liquid properties were examined. The results show that minimum film thickness and friction coefficient increases when lubricant viscosity increases. At the same time, for increasing of elastic modulus of bearing bushing the friction coefficient decreases.


2019 ◽  
Author(s):  
Md. Arefin Kowser ◽  
Mohammad Lutfar Rahman ◽  
Md. Mohi Uddin ◽  
Mohammad Asaduzzaman Chowdhury ◽  
Rajib Nandee

2017 ◽  
Vol 177 ◽  
pp. 554-561 ◽  
Author(s):  
Alzbeta Sapietova ◽  
Juraj Bukovan ◽  
Milan Sapieta ◽  
Lenka Jakubovicova

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