OME tool can … It looks that a preference of the polytropic efficiency in a gas compressor community is from a historical background. k may be estimated from molecular weight and temperature correlations or obtained from a commercial simulation program. Contents. 2.11, where the polytropic efficiency of the compressor and turbine is assumed to be 0.87. … The part we are going to … In the previous paper, we introduced the more efficient fixed displacement rotary vane compressors (new CR series) for car air conditioners. The polytropic head is a function of pressure ratio across the compressor and therefore will result in a pressure rise, assuming the inlet pressure is not changed. Results and Discussions. The basics of these methods have been defined by Mr. Dzung who was working for Brown Boveri & Cie in the forties of the last century. Stage efficiency and polytropic efficiency is 84 % and 87 %. results of polytropic head and efficiency versus design compressor curves provided by the Manufacturer. b. Inserting this into the definition of the normal Isentropic Efficiency allows one to compute it in terms of η Poly and the finite pressure or temperature ratio: $ % 1 # c $ % #! If you plot a P-V curve for the compression process and … For an ideal gas in a closed system undergoing a slow process with negligible changes in kinetic and potential energy the process is polytropic, such that (−) + =where C is a constant, =, =, and with the polytropic coefficient = (−) +. These parameters describe how efficiently a turbine, compressor or nozzle approximates a corresponding isentropic device. DEPARTMENT OF MECHANICAL ENGINEERING, GHOUSIA COLLEGE OF ENGINEERING, RAMANARA -562159 . A trend of decreasing isentropic compressor efficiency is seen when increasing pressure ratio (at constant polytropic efficiency) (Saravanamuttoo et al., 2001, p. 61). Polytropic Compression: The practical understanding of the polytropic process and its usage in defining the compression process and efficiency is a development of the last three decades. NPTEL Phase-I under grant in aid NMEICT, MHRD, New Delhi . Double flow ducted dehumidifier line The DPG-DF series highly efficient dehumidifiers with energy recycling (double flow) are high quality appliances with the following specifications: Full insulation for indoor use. Input power is the electric power supplied to the electric motor . Determination of the ideal or isentropic (reversible and adiabatic) enthalpy change (h 2Isen-h 1) of the compression process. However the isentropic and polytropic efficiencies could be estimated and were used to more accurately assess the performance of the compressor. Motor efficiency:- It is the ratio of shaft power to the input Power. The compressor is a standard single-stage barrel/bundle type centrifugal with a polytropic efficiency of >86%. The further these conditions on site deviate from those prescribed at design, the less accurate the health assessment of the compressor becomes. Calculate the polytropic efficiency η Poly) by Equation 8. e. Calculate the isentropic and polytropic heads by Equations 9 and 10, respectively. Assume steady state, i.e. This ratio is known as the Isentropic Turbine/Compressor/Nozzle Efficiency. The real-gas equations of polytropic analysis are derived in terms of compressibility functions X and Y which supplement the familiar compressibility factor, Z. The overall efficiencies are given by: m a oa . The inlet stagnation conditions are 15°C and 101.3 kPa. This paper describes the technology involved in analysis of compressor power, used in development of new series of Compressors . 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