Question

In: Mechanical Engineering

Consider a turbine; working substance is air. cp=1.0 kJ/kgK ,    k=1.4 v1=0.03 ,    v2=0.08 m3/kg ,    ...

Consider a turbine; working substance is air.

cp=1.0 kJ/kgK ,    k=1.4

v1=0.03 ,    v2=0.08 m3/kg ,     p1=2.5 bar; state 1 is enterance, state 2 is the exit of the turbine. The turbine is not ideal (isentropic); the air goes through a state change according to pv^n=constant ,      n=1.6 Compute the ideal and actual specific works and turbine efficiency.

pvn=constant ,      n=1.6

Solutions

Expert Solution

One assumption is made while solving the problem is that the exit condition given is for actual condition and considering it the ideal condition is calculated.

one important concept while dealing with the ideal and the actual condition is that the pressure at entry and exit are the same so there is a need to calculate the specific volume at the entry and the exit condition for the actual and the ideal case.

all the above entry and exit condition for the actual and ideal case is evaluated to calculate the work done for both the condition with the help of direct formula for an adiabatic and polytropic process for open system and then determine the required efficiency of the turbine.

comment if any query.


Related Solutions

Air (cp = 1.0 kJ/kgK) enters an air conditioning system at 40C with a mass flow...
Air (cp = 1.0 kJ/kgK) enters an air conditioning system at 40C with a mass flow rate of 1.5 kg/s. The air is cooled by exchanging heat with a stream of R-134a refrigerant that enters the heat exchanger at -8C and 20% quality, and exits with 100% quality. If 25 kW of heat is transferred out of the air, determine: (40 pts) i) Mass flowrate of R-134a (kg/hr) ii) Exit temperature of air (C) iii) Exit pressure of R-134a (kPa)
Air (Cp = 1.005 kJ/kg · K) is to be preheated by hot exhaust gases in...
Air (Cp = 1.005 kJ/kg · K) is to be preheated by hot exhaust gases in a cross-flow heat exchanger before it enters the furnace. Air enters the heat exchanger at 95 kPa and 20◦C at a rate of 0.90 kg/s. The combustion gases (Cp = 1.1 kJ/kg · K) enter at a rate of 1.1 kg/s and 150◦C. The product of the overall heat transfer coefficient and the heat transfer surface area is U A = 1200 W/K. Assuming...
Water ( ρ= 1000 kg/m3; Cp= 4.2 kJ/kg.K; k= 0.58 W/m.K ) at 1,537 kg/hr and...
Water ( ρ= 1000 kg/m3; Cp= 4.2 kJ/kg.K; k= 0.58 W/m.K ) at 1,537 kg/hr and 26oC enters a 10-mm-diameter smooth tube whose wall temperature is maintained at 79oC. If the water's Nusselt number (Nu) = 375, and the tube length is 7.6, calculate the water outlet temperature,in oC.
A stainless steel ball (? = 8055 kg/m3 , CP = 480 J/Kg? K ) of...
A stainless steel ball (? = 8055 kg/m3 , CP = 480 J/Kg? K ) of diameter D = 15cm is removed from the oven at a uniform temperature of 350 Degrees C. The ball is then subjected to the flow of air at 1 atm pressure and 30 degrees C with a velocity of 6m/s. The surface temperature of the ball eventually drops to 250 degrees 250 degrees C. Determine the average convection heat transfer coefficient during this cooling...
Water flowing at a rate of 0.667 kg/s (Cp = 4.192 kJ/kg. K) enters a counter...
Water flowing at a rate of 0.667 kg/s (Cp = 4.192 kJ/kg. K) enters a counter current heat exchanger at 318 K and is heated by an oil stream entering at 393 K at a rate of 2.85 kg/s (Cp=1.89 kJ/kg. K). The overall U=290 W/m2. K and the area A=20 m2. Calculate the heat transfer rate and the exit water temperature.
A gas with cp = 0.950 kJ/kg-K enters an insulated nozzle at 30oC and a velocity...
A gas with cp = 0.950 kJ/kg-K enters an insulated nozzle at 30oC and a velocity of 8 m/s. The gas exits at a velocity of 100 m/s. Assuming constant specific heats and ideal gas behavior, what is the exit temperature of the gas?
A 1.0 m3 tank, initially filled with 103. kPa, 300. K air, is connected to a...
A 1.0 m3 tank, initially filled with 103. kPa, 300. K air, is connected to a source of air at 1,500. kPa, 300. K. The tank slowly fills until it is at the same pressure. If the temperature is maintained at 300. K throughout this transient process, what is the total heat transfer required? (You can assume air is an ideal gas.)
FIreclay brick (ρ=2050 kg/m3, cp=960 J/kg-K, k=1.1 W/m-K) with dimensions 0.06 m x 0.09 m x...
FIreclay brick (ρ=2050 kg/m3, cp=960 J/kg-K, k=1.1 W/m-K) with dimensions 0.06 m x 0.09 m x 0.20 m is removed from a kiln at 1600K and cooled in air at 40C with h = 30 W/m2-K. What is the temperature at the corner of the brick after 50 minutes of cooling? Give your answer in degrees C.
Consider a piston cylinder device with a volume of 0.04 m3 and initially contains air at 293 K and 1 bar.
  Consider a piston cylinder device with a volume of 0.04 m3 and initially contains air at 293 K and 1 bar. It is desired to reverse the cycle and use it as a refrigerator. In this case the process would begin with PV1.36 = constant process from an initial state of 293 K and a pressure of 10 Bars. The gas is allowed to expand to a volume 3.5 times the volume of state 1. It then follows a...
Determine the specific volume (m3/kg) of air at T = 159.6 K and P = 37.5 bar using the generalized compressibility chart.
  Determine the specific volume (m3/kg) of air at T = 159.6 K and P = 37.5 bar using the generalized compressibility chart.  
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT