Abstract
This work investigates the start-up characteristics of linear compressors in a refrigeration system through experiment and simulation. Experiments are carried out by a refrigeration test system with a linear compressor controlled by a LabVIEW platform. A simulation model that considers the nonlinear process of gas force is set up on the basis of Runge-Kutta method for linear compressors. Compared with the experimental results, the simulation errors are within 15%, including the unstable state. The influences of ambient temperature and power frequency on linear compressors are studied through experiments. Unstable phenomena exist at 25°C ambient temperature compared with the designed ambient temperature of 35°C. The unsteadiness mechanism is analyzed by simulation. Simulation analysis indicated that two sensitive stages of linear compressors, namely, starting to pump and touching top dead center, are unstable. Furthermore, properly increasing equivalent mass (approximately 3%) or spring stiffness during the design stage can be a practical method to improve the stability of linear compressors.
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Abbreviations
- A :
-
piston sectional area/m2
- c :
-
equivalent damping coefficient/N·s·m−1
- c f :
-
friction damping coefficient/N·s·m−1
- Fe:
-
electromagnetic force/N
- F g :
-
force load acting on the piston/N
- f :
-
power frequency/Hz
- f d :
-
inherent frequency with damping/Hz
- f n :
-
inherent frequency without damping/Hz
- H :
-
piston stroke/m
- I :
-
effective current/A
- i :
-
current/A
- K 0 :
-
electromagnetic force coefficient/N·A−1
- k s :
-
stiffness coefficient of syntonic springs/N·m−1
- k d :
-
stiffness coefficient of discharge springs/N·m−1
- k :
-
equivalent stiffness coefficient/N·m−1
- L e :
-
equivalent inductance/H
- m 1 :
-
moving part mass/kg
- m 2 :
-
frame mass/kg
- N:
-
discrete points of each cycle for simulation
- P i :
-
input power/W
- P o :
-
output power/W
- P c :
-
pressure inside of the cylinder/Pa
- p d :
-
discharge pressure/Pa
- p s :
-
suction pressure/Pa
- p :
-
pressure/Pa
- R e :
-
equivalent resistance/Ω
- r 1 :
-
leakage rate
- U :
-
effective voltage/V
- U a :
-
voltage amplitude/V
- u :
-
supply voltage/V
- v :
-
piston velocity/m·s−1
- X d :
-
preload distance of discharge spring/m
- X i :
-
piston initial clearance position/m
- x t :
-
dispersed displacement/m
- x :
-
piston displacement/m
- η :
-
compressor efficiency
- η m :
-
linear motor efficiency
- κ :
-
adiabatic index
References
Pérez-Segarra C.D., Rigola J., Sôria M., et al., Detailed thermodynamic characterization of hermetic reciprocating compressors. International Journal of Refrigeration, 2005, 28(4): 579–593.
Zhao B., Jia X., Zhang Y., et al., Investigation on transient temperature of a reciprocating compressor based on a two-thermocouple probe. International Journal of Thermal Sciences, 2017, 122: 313–325.
Boldea I., Nasar S.A., Linear actuators and generators. IEEE Transactions on Energy Conversion, 1997, 14(3): 712–717.
Han Y.Q., Kang J.J., Zhang G.P., et al., Performance evaluation of free piston compressor coupling organic Rankine cycle under different operating conditions. Energy Conversion and Management, 2014, 86: 340–380.
Zhang A.K., Wu Y.N., Liu S.S., et al., Effect of impedance on a compressor driving pulse tube refrigerator. Applied thermal engineering, 2017, 124: 688–694.
Mahmoud A.A, Zhang T.J., Characterization of energy efficient vapor compression cycle prototype with a linear compressor. Energy Procedia, 2015, 75: 3253–3258.
Jia B.R., Andrew S., Zuo Z.X., et al., Design and simulation of a two- or four-stroke free-piston engine generator for range extender applications. Energy Conversion and Management, 2016, 11: 289–298.
Unger R., Development and testing of a linear compressor sized for the European market. International Appliance Technology Conference, Purdue University, 1999.
Bradshaw C.R., Groll E.A., Garimella S.V., Linear compressors for electronics cooling: Energy recovery and its benefits. International Journal of Refrigeration, 2013, 36(7): 2007–2013.
Lee H.K., Song G.Y., Park J.S., et al., Development of the linear compressor for a household refrigerator. In: Proceedings of International Compressor Engineering Conference, Purdue University, 2000.
Liang K., Richard S., William H., Mike D., Paul B., Comparison between a crank-drive reciprocating compressor and a novel oil-free linear compressor. International Journal of Refrigeration, 2014, 45: 25–34.
Hanson B., Levesley M., Self-sensing applications for electromagnetic actuators. Sensors and Actuators A. Physical, 2004, 116: 345–351.
Sung J.W., Lee C.W., Kim G.S., et al., Sensorless control for linear compressors. International Journal of Applied Electromagnetics and Mechanics, 2006, 24: 273–286.
Chun T.W., Ahn J.R., Yoo J.Y., et al., Analysis and control for linear compressor system driven by PWM Inverter. The 30th Annual Conference of the IEEE Industrial Electronics Society, Busan, Korea, 2004, 263–267.
Lee H., Ki S.H., Jung S.S., Rhee W.H., The innovative green technology for refrigerator. In: Proceedings of International Compressor Engineering Conference, Purdue University, 2008.
Kim H., Roh C., Kim J., et al., An experimental and numerical study on dynamic characteristic of linear compressor in refrigeration system. International Journal of Refrigeration, 2009, 32: 1536–1542.
Yoo J.Y., Park S., Lee H., Jeong S., New capacity modulation algorithm for linear compressor. International Compressor Engineering Conference at Purdue, July 12–15, 2010.
Kim J.K., Roh C.K., Kim H., Jeong J.H., An experimental and numerical study on an inherent capacity modulated linear compressor for home refrigerators. International Journal of Refrigeration, 2011, 34: 1415–1423.
Kim J.K., Jeong J.H., Performance characteristics of a capacity-modulated linear compressor for home refrigerators. International Journal of Refrigeration, 2013, 36: 776–785.
Kim J.K., Kim J.B., Modulation characteristics of a linear compressor for evaporating and condensing temperature variations for household refrigerators. International Journal of Refrigeration, 2014, 40: 370–379.
Hwang I.S., Oh W., Park K., et al., A study on two phase flows of linear compressors for the prediction of refrigerant leakage. Journal of Mechanical Science & Technology, 2015, 29(11): 4737–4743.
Zou H.M., Tang M.S., Xu H.B., et al., Performance characteristics around the TDC of linear compressor based on whole-process simulation. Journal of Mechanical Science and Technology, 2014, 28: 1–9.
Zou H.M., Tang M.S., Shao S.Q., et al., Investigation on the jump phenomenon of linear compressor. Mechanitronics, 2014, 243–252.
Choe G.S., Kim K.J., Theoretical and experimental analysis of nonlinear dynamics in a linear compressor. Journal of Vibration & Acoustics, 2002, 124(1): 621–632.
Yu Y.Z., technology manual of displacement compressor. Machinery Industry Press, 2000, pp. 38–48. (In Chinese)
Acknowledgement
We would like to thank the support from the National Natural Science Foundation of China (No. 51576203 and No. 51976229). And this study is also supported by CAS Key Laboratory of Cryogenics, TIPC (No. CRYOQN201908). Dr. Tang M.S. is supported by Youth Innovation Promotion Association, CAS (No. 2018032).
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Zou, H., Li, X., Tang, M. et al. Start-up Characteristics of Linear Compressors in a Refrigeration System. J. Therm. Sci. 30, 598–609 (2021). https://doi.org/10.1007/s11630-020-1325-z
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DOI: https://doi.org/10.1007/s11630-020-1325-z