A Method for Determining the Volume of the Working Cavity of a Screw Compressor

Grapho-analytical, analytical and numerical methods are currently used to calculate the relationship between the volume of the screw compressor working cavity and the rotation angle of the driving rotor. However, the complexity of the grapho-analytical and numerical methods impede their practical application. The analytical method is suitable for calculating symmetrical profiles but it results in unacceptable errors when calculating screws of asymmetrical profile. This paper presents an approximated method for determining an analytical dependence of the volume of the screw compressor working cavity on the rotation angle of the driving rotor. Ways to determine the initial volume, angles of suction, pressurization, and compression are shown. The suggested method is tested through calculating volumes of the screw working cavities in standard series and comparing the results with the standard series data. It is shown that the obtained analytical relationships between the volume of the working cavity filled with gas, and the rotation angle of the driving rotor can be used for calculating components of the flow section in screw compressors with asymmetric profile rotors. 

References

[1] Shershnev O.V. Primenenie DKU Enerproject pri utilizatsii poputnogo neftianogo gaza v kachestve topliva dlia GTES [Application DKU Enerproject for disposal of associated petroleum gas as fuel for the gas turbine power plant]. Turbiny i dizeli [Turbines and diesel engines]. 2011, no. 5, pp.16–17.

[2] Avtonomova I.V., Shur A.Iu. Utilizatsiia PNG: osobennosti ekspluatatsii kompressornykh ustanovok s vintovymi maslozapolnennymi kompressorami na gaze povyshennoi plotnosti [APG utilization: features of operation of compressor units with screw compressors Oilinjected gas increased density]. Neftegazovaia vertikal’ [Oil and Gas Vertical]. 2014, no. 4(329), pp. 52–56.

[3] Avtonomova I.V., Korolev D.V. Analiz vliianiia otnositel’noi dliny rotorov vintovogo kompressora na ego parametry [Analysis of Influence of Relative Rotor Length of Screw Compressor on Its Parameters]. Vestnik MGTU im. N. E. Baumana. Ser. Mashinostroenie [Herald of the Bauman Moscow State Technical University. Mechanical Engineering]. Spets. vyp. Vakuumnye i kompressornye mashiny i pnevmooborudovanie, 2011, pp. 69–77.

[4] Prince K.G. Environmental design and product development innovation in variable-speed oil-free rotary screw compressors. International Conference on Compressors and their Systems, 9-12 September 2001, City University, London, UK, pp. 91–110.

[5] Avtonomova I.V., Mazurin E.B., Bratus’ A.V. Razrabotka tekhnologicheskoi skhemy KU s rekuperatsiei tepla. Analiz i podbor konstruktsii promezhutochnogo okhladitelia [Development of Flowchart of Compressor Unit with Heat Recuperation. Analysis and Selection of Intermediate Cooler Construction]. Vestnik MGTU im. N. E. Baumana. Ser. Mashinostroenie [Herald of the Bauman Moscow State Technical University. Mechanical Engineering]. Spets. vyp. Vakuumnye i kompressornye mashiny i pnevmooborudovanie, 2011, pp. 78–98.

[6] Sato H. Development of high-pressure screw compressor. International Conference on Compressors and their Systems 9-12 September 2001, City University, London, UK. pp. 111–119.

[7] Andreev P.A. Vintovye kompressornye mashiny [Screw compressor machine]. Leningrad, Sudpromgiz publ., 1961. 252 p.

[8] Chekushkin G.N., Khamidullin M.S., Nalimov V.N. Chislennyi metod profilirovaniia i analiza geometrii rabochikh kamer rotornykh kompressorov [A numerical method for profiling and analyzing the geometry of the working chambers rotary compressors]. Kazan’, KKhTI publ., 1988. 25 p.

[9] Sakun I.A. Vintovye kompressory [Screw compressors]. Leningrad, Mashinostroenie publ., 1970. 400 p.

[10] Stosic N., Smith I. K., Kovacevic A. Screw Compressors. Mathematical Modelling and Performance Calculation. Springer, 2004. 138 p.

[11] Stosic N., Smith I. K., Kovacevic A. Screw Compressors. Three Dimensional Computational Fluid Dynamics and Solid Fluid Interaction. Springer, 2007. 158 p.

[12] Kovacevic A., Stosic N., Smith I.K. Three Dimensional Numerical Analysis of Screw Compressor Performance. Journal of Computational Methods in Science and Engineering, 2003, vol. 3, no. 2, pp. 259–284.

[13] Kovacevic A., Stosic N., Smith I.K. A Numerical Study of Fluid-Solid Interaction in Screw Compressors. International Journal of Computer Applications in Technology, 2004, vol. 21, no. 4, pp. 148–158.

[14] Kovacevic A: Boundary Adaptation in Grid Generation for CFD Analysis of Screw Compressors. International Journal for Numerical Methods in Engineering, 2005, vol. 63, pp. 138–152.

[15] David Buckney, Ahmed Kovacevic, Elvedin Mujic, Nikola Stosic Some Aspects of Estimating Geometric Characteristics of Screw Compressors. International Compressor Engineering Conference at Purdue, 2012, no. 1454, рр. 1–10.

[16] Amosov P.E., Bobrikov N.I., Shvarts A.I., Vernyi A.L. Vintovye kompressornye mashiny. Spravochnik [Screw compressor machine. Directory]. Leningrad, Mashinostroenie publ., 1977. 256 p.