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Homework Help: Thermodynamics Cycles (Piston Question)

  1. Oct 18, 2011 #1
    A 4 cylinder car has 4 Pistons
    The cycle is
    1-2 : Adiabatic compression of air
    - then injects fuel
    2-3 : Burn Fuel
    3-4 : Adiabatic expansion of gas
    4-1 : Exchaust / Replace with fresh air


    1. The problem statement, all variables and given/known data

    Diameter = 10 cm
    Minimum depth 1 cm
    Maximum depth 10 cm
    Heating value of fuel is 2,100 j/g
    Each cycle uses 0.005g of fuel
    Temp of air = 25 degree celcius
    Pressure of air = 101 325 Pa

    2. Relevant equations
    Draw P-V Diagram
    Calculate P,T,V at all points (1,2,3,4)
    Calculate power produced by car at 100 RPM , 500 RPM and 1000 RPM

    3. The attempt at a solution
     
  2. jcsd
  3. Oct 18, 2011 #2
    So basically.. I have the P-V Diagram..
    To my understanding you need to calculate power produced by car at 100 RPM to get P,T,V at all points..

    Any help? PLEASE
     
  4. Oct 18, 2011 #3
    Hint: Polytropic relationships
     
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