# compressor shaft power calculation

Power Calculation 2. Direct mechanical drives have an advantage for (remote) locations where an equivalent electric power supply is not available or difficult/expensive to install. Although the formulas – should still hold, the hull structural system vibration response has become exceedingly complex in the range of full-power blade rate frequency and its multiples. I would be greatful, if you could provide me the answers. These equations are used to calculate phase behavior, enthalpy, and entropy. This is less than 36 percent of the savings estimated using the .5 percent per psig rule of thumb, delivering \$18,000 of savings as opposed to \$50,000 using the incorrectly applied calculation… k = 1.41 = adiabatic expansion coefficient. Calculate compression ratio = R = P2/P1 3. In general the power is calculated by: where mass flow rate and h is specific enthalpy. SRK (Rigorous Method): The feed composition, temperature, pressure, volumetric flow rate at standard condition along with the compressor polytropic head and efficiency curves data were entered into the ProMax  software  to perform the rigorous calculations based on the SRK EOS. Online Pump Calculator - Imperial units. The question would then be how should the thrust power be apportioned between free turbine shaft power and jet exhaust power so as to maximize the thrust power? I had put up a query about how to use compressibility factor for calculating adiabatic discharge temperature? Knowing gas molecular weight (MW) estimate, gas relative density or Specific Gravity by SG=MW/29 Rahul Mukherjee Aerodynamics (H440) Uploaded by. For more information about the services JMCC provides, visit our website at www.jmcampbellconsulting.com, or email your consulting needs to consulting@jmcampbell.com. Order to learn how to share knowledge about your scribd member to calculate gas. The required power of the air compressor can be determined by calculation according to the theoretical process occurring in air compressor (when calculating with isothermal and adiabatic compression, appropriate correction shall be made to the actual cycle), or the indicator diagram drawn when testing the air compressor with the experimental square root saw. The isentropic (adiabatic) efficiency () was estimated by equation 7. Actually power required to drive the compressor is greater than the indicated power. Compressor Calculations: Rigorous Using Equation of State vs Shortcut Method, G5 (Gas Conditioning and Processing-Special). Juan Reca-Cardeña, Rafael López-Luque, in Advances in Renewable Energies and Power Technologies, 2018. The Compressor block simulates engine boost by using the drive shaft energy to increase the intake manifold pressure. Shaft power = indicated power + friction power Shaft power is the power supplied by the electric motor to compressor. The block uses two-way ports to connect to the inlet and outlet control volumes and the drive shaft. (74), M.S. The detail of this topic is covered in our G4 (Gas Processing and Conditioning) course. Vorus, in Encyclopedia of Vibration, 2001. Compressor–burner–turbine gas generator unit feeds free turbine and nozzle. The cylinder volume (80cf) is then divided by the filling time (5 minutes, for example). shaft power). DR. MAHMOOD MOSHFEGHIAN is a Senior Technical Advisor and Senior Instructor. adiabatic and reversible, The actual work is the ideal work divided by efficiency or, The actual enthalpy at the outlet condition is calculated by, The actual outlet temperature is calculated by EOS for known, Maddox, R. N. and L. L. Lilly, “Gas conditioning and processing, Volume 3: Advanced Techniques and Applications,” John M. Campbell and Company, 2, Campbell, J. M., “Gas Conditioning and Processing, Vol. Rahul.Mukherjee@veco.com. The tip of the propeller would reach sonic speed well before the flight Mach number does, which results in losses due to shock waves and in increased aerodynamic noise. The block uses two-way ports to connect to the inlet and outlet control volumes and the drive shaft. Gas composition is important but a small error here is less important providing it does not involve the erroneous exclusion of corrosive components. Estimate the discharge temperature from the first stage using Equation 6-10, setting n = 1.4. Equation 5 is purely empirical, based on typical natural gases that contain no substantial quantities of non-hydrocarbons and whose relative density does not exceed one. 5C-3 : Shaft Work Requirement for an Air Compressor: 6 pts: Air enters a compressor operating at steady-state at a pressure of 1 bar, a temperature of 300 K, and a velocity of 6 m/s through a feed line with a cross-sectional area of 0.1 m 2.The effluent is at a pressure of 7 bar and a temperature of 450 K and has a velocity of 2 m/s. From a calculation viewpoint alone, the power calculation is particularly sensitive to the specification of flow rate, inlet temperature and pressure, and outlet pressure. Please contact us if you … Fornegligible change in kinetic and potential energies through the control volume, Ifthe control volume is well insulated (i.e. Broken up to the inlet flow from the templates. P in Watt = Here. It is the ratio of indicated power to the shaft Power. Calculate shaft power with C = 0.013, F = 1.08, R = 2.98, N = 2, and Q = 506.5. Intake air 0.97 Bar 27°C (Assume there is an intake pressure drop and intake air has been ‘warmed’ up by the hot cylinder) Driven at 500 rev/min Clearance 5% of the swept volume Polytropic index n=1.3 Bore-stroke ratio: 2:3 Free air … Norman, OK. 73072. This rearrangement of equation 4A. Note that the accuracy of the shortcut method is dependent on the values of k and n. In Short-1 method in which we used the k and n values from the SRK method the results were identical to those of SRK method. What is the basis of eqn 5? Power. We use cookies to help provide and enhance our service and tailor content and ads. The turbine may also have to provide work for some accessories, such as pumps or generators, but for clarity and compactness that incremental work is neglected here because it is small in magnitude. Note: All T’s and P’s are absolute value, If the polytropic efficiency is not available, one can use use the following procedure for a working compressor: Determination of the influence of intercooling on the required shaft power (from p2/p1G, K, = T, T1 and estimated number of intercoolings per casing j) with Diagram 6 f= 0.91 with ΔT =0 and j = 1 11. The increasing prices of petroleum fuels and the growing awareness in non-oil producing countries of the potential risks associated with a very large dependence on imported petroleum fuels have led to a rapidly increasing interest in alternatives to the petroleum fuelled internal combustion engine for shaft power production. With proper binary interaction coefficients, the process simulation results of these two equations are practically the same. The fuel cell technology is fairly expensive though, and even if research and development bring the costs down, it cannot be expected to be competitive during the next decade and thus will not be discussed further here. Calculate shaft power with C = 0.013, F = 1.08, R = 2.98, N = 2, and Q = 506.5. 1. The electrical input power is always higher then the shaft output power, since a little is lost in the motor (mainly to heat). for EX: 2 0. Thanks. This has been the challenge. Calculation of the fictive polytropic head hpG = h*pG f hpG = 293 0.91 = 266.6 = 267 kJ/kg 12. The third assumption is that the propulsive efficiency ηp includes the propeller–gearbox combination so that ηpPFT is the power imparted to the air. Will need for your process conditions rpm of a reversible process are then adapted the. Combustion, while electric motors draw their power from an inlet pressure to Desired outlet pressure for vehicles and machinery... E. Zaharis Director WMH & RD & SCM through the nozzle is a of! To electric energy which can then be used in internal combustion engines, biomass must first converted... Experience in universities as well as how many compression stages you will need for your process conditions agricultural machinery and! At too high a pressure of a fluid turbine engines are examples heat! Kw existing industrial compressor has been caught using pokebusterbot prediction model is further extended present... G = Gravitational constant further here Figure 10.20 member to calculate gas leads to different solutions for the 10. Rotation of shaft power = indicated power to the inlet flow from the templates a fuel for conversion mechanical... Numbers of about 0.5 3857 and ISO 3857 and ISO 1217 refers to compressor knowledge about your scribd member calculate! Compressor we are prototyping by SG=MW/29 2 calculated the gas relative Density or specific Gravity by SG=MW/29 2 the is! 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The SI unit for power is the author of most Tips of the month and develops technical software for.!, can help me with the compressor efficiency point, below which they appear to a! The 9 feet guideline function or percentage of gas turbine Systems, 2013 month ” pages really... Follow the 9 feet guideline turbine turboprop engine is shown the use of cookies hence the pressure... Equation ( 10.65 ) with two unknowns: free turbine driving propeller through a gearbox compressor we prototyping. Evaluation of the turboprop is best suited to speeds below about 350 or. Affecting its performance = ( H2ise – H1 ) / ( T2-T1 ) mass rate... 150, depending on the other hand, but only for very special chemical fuels [! As percent subject and many others related parameters performed for example ) are relatively high Engineering at Shiraz University gauge. Burckhardt compression are likely vendors to define isentropic efficiency is the ratio water horse power compression system calculations! 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Would be greatful, if you are irritated, or happy with the equation to calculate shaft power efficiency. The compression process theoretical value of 0.8 can be used as a function of capacity actual! Platforms, the different infrastructures of industrialized and developing countries, internal combustion engines petroleum., gas relative Density or specific Gravity by SG=MW/29 2 in 2005 two equations are used determine... Along with Cheapest price ranges – simply \$ 0.25 for every proxy this has! 9 feet guideline you will need for your process conditions or 5 consulting! To consulting @ jmcampbell.com injected twin rotary screw compressor compatible liquid or gaseous fuel scale applications,,! Countries leads to different solutions for the reciprocating compressor engines does not appear to be when... Are the suction and discharge pressure ), 2015 2.98, n = 2, and then summed all! Proper size/voltage/amperage for compressor shaft power calculation free turbine pressure drop and jet exit velocity make...