Please give me the equation with a link if possible for determining power for a compressor. The effect of varying compressor efficiency on the COP of the three GSHP system configurations are presented in Fig. Lubricating oil reduces the operating temperature of the compressor, reduces friction (thus increasing compressor operating efficiency and output), minimizes air leakage around piston rings, and it The compressor isentropic efficiency and shaft speed is obtained with interpolation. The total power requirement of a compressor for a given duty is the sum of the gas power and the friction power. CiteSeerX - Document Details (Isaac Councill, Lee Giles, Pradeep Teregowda): Many standard efficiency denitions exist that qualify the mass flow and power performance characteristics of a compressor. η C = Isentropic compressor (pump) work/Actual compressor (pump) work Compressors and pumps, when undergo a steady-flow process, consume power.  for low to high efficiency compressors. SP values of non-inverter type oil-free air compressor marketed in Thailand are calculated from values of the obtained 17 catalogue data with the equation as indicated in the proposed methodology. the one you can possibly convert into work thanks to an ideal process. → Temp increase from T1 to T2. And the characteristics of the partly loaded compressor increase the power requirement to 16.8 kW (10.5 x 1.6 = 16.8 kW) This requirement of 16.8 kW is over 22 times the actual power delivered by the motor! In general, increasing the pressure ratio is the most direct way to increase the overall thermal efficiency of a Brayton cycle, because the cycle approaches the Carnot cycle. For Polytropic process . A) There is a loss due to the non-isothermal nature of the compression process. h lc = enthalpy of vapor leaving compressor (Btu/lb) h ec = enthalpy of vapor entering compressor (Btu/lb) Volumetric Efficiency . Overcoming pressure drop increases the power further to 10.5 kW (9.75 x 1.075 = 10.5 kW). Figure 3.24(a) shows the gas turbine engine layout including the core (compressor, burner, and turbine). This parameter reduces the overall efficiency and work output. 9, based on the results of previous investigations [24,49].The compressor isentropic efficiency is varied from 65% to 100% for each of the heat pump systems, following the range given by Cengel et al. The gas power is directly proportional to head and mass flow and inversely proportional to efficiency. Specific exergy of any gas is the useful energy contained within it, i.e. NEMA Efficiency – 87.5 Service Factor – 1.15. So additional work is needed to overcome the inefficiency of the compressor to produce a desired CPR. Compressor efficiency can be defined as the ratio between this enthalpy increase and the actual measured enthalpy increase, i.e. These parameters describe how efficiently a turbine, compressor or nozzle approximates a corresponding isentropic device. When making decisions about energy efficiency, we need some accurate information to plug into power cost formulas.In past years, there has been a jumble of information based on a variety of test conditions. Shaft power = indicated power + friction power Shaft power is the power supplied by the electric motor to compressor. Z = V actual/V ideal Power Requirements For isentropic compression & efficiency: (15) is the mass flow rate; z avg is the average of the inlet & outlet compressibility factors 20 = Pv Z RT m A turbocharger, colloquially known as a turbo, is a turbine-driven, forced induction device that increases an internal combustion engine's efficiency and power output by forcing extra compressed air into the combustion chamber. This formula for calculating efficiency is in line with first law of thermodynamics.Which deals with the conservation of quantity of energy (not quality). 1. Homework Equations The equation we were given to used: isentropic efficiency = (air mass flow rate * Difference in stagnation pressure across the compressor)/ (air density * compressor shaft torque * shaft rotational speed) The Attempt at a Solution By comparing the efficiency, nominal amperes at the rated voltage, a quick determination of the real horsepower can be made: Rated Horsepower – 5 Volts – 230 Amperes – 13.8. Using the manometer heights we was asked to calculate the isentropic efficiency. w t = theoretical weight of refrigerant. For turbines, the value of η T is typically 0.7 to 0.9 (70–90%). There must be a better way. ELGi produces air compressors that drive a vast range of vital year–round operations, including industrial, manufacturing, food packaging, construction and auto assembly. The thermal efficiency in terms of the compressor pressure ratio (PR = p 2 /p 1), which is the parameter commonly used:. We all know the general formula for calculating efficiency of a heat engine.It is a ratio of output work to input heat. Mechanical losses in the bearings and, to a lesser extent, in the seals are the primary source of friction power. Compressor … 1 – 2 : Air compressed according to PVn = Const. The gas power is directly proportional to head and mass flow and inversely proportional to efficiency. imple equation is often used to obtain the polytropic efficiency of the centrifugal compressors by replacing γ by isentropic index of compression, k, i.e., for actual refrigerants the polytropic efficiency is estimated from the equation: where γ = spec Though refrigerant …