3) Air flows steadily at the rate of 0.4 kg/sthrough an air compressor, entering at 6 m/s with a pressure of 1bar and a specific volume of 0.85 m3/kg, and leaving at 4.5 m/swith
     a pressure of 6.9 bar and aspecific volume of 0.16 m3/kg. The internal energy of air leavingis 88 kJ/kg greater than that of the air entering. Cooling water ina jacket surrounding the cylinder absorbs heat from the air at therate of 59 kJ/s. (i) Calculate the power required to drive thecompressor and (ii) the inlet and outlet pipe cross-sectionalareas.
4) Steam enters a turbine at 20 m/s and specific
          enthalpy of 3000 kJ/kg and leaves the turbine at
          40m/s and specific enthalpy of 2500 kJ/kg. Heat
          lost to the surroundings is 25 kJ/kg of steam as the
          steam passes through the turbine.
5) A turbine, operating under steady-flow conditions, receives5000 kg of steam per hour. The steam enters the turbine at avelocity of 3000 m/min, an elevation of 5 m and a specific enthalpyof 2787 kJ/kg. It leaves the turbine at a velocity of 6000 m/min,an elevation of 1 m and a specific enthalpy of 2259 kJ/kg. Heatlosses from the turbine to the surroundings amount to 16736 kJ/h.Determine the power output of the turbine.
          Ifthe steam flow rate is 360000 kg/h, determine the
          output from the turbine in MW.
6) A refrigerator operates on reversed Carnot cycle.
   Determine the power required to driverefrigerator
   between temperatures of 42oC and 4oC if heatat the
   rate of 2 kJ/s is extracted from the lowtemperature
   region.
7) In a winter season when outside temperature is
    –1oC, the inside of house is to bemaintained at
     25oC. Estimate the minimum powerrequired to run
     the heat pump of maintaining thetemperature.
     Assume heating load as 125MJ/h.
8) What would be maximum efficiency of engine that
    can be had between the temperatures of1150oC
     and 27oC ?
9)A heat engine is supplied with 278 kJ/s of heat at a constantfixed temperature of 283°C and the heat rejection takes place at5°C. The following results were reported :
(i) 208 kJ/s are rejected, (ii) 139 kJ/s are rejected, (ii) 70kJ/s are rejected.
   Classify which of the results report areversible cycle or irreversible cycle or impossible results.
10) An air-standard Otto cycle has a compression ratio of 9. Atthe beginning of the compression process, the temperature is 20°C,and the pressure is 100 kPa. The heat added is 500 kJ/kg. Determinethe cycle efficiency, work output, and the heat rejected.
11)An air-standard Otto cycle operates with a minimumtemperature of 300 K and a maximum temperature of 1700 K. Thecompression ratio of the cycle is 7. At the beginning of thecompression process, the pressure is 105 kPa. Calculate P, V, and Tat each point in the cycle, the mean effective pressure, and thethermal efficiency of the cycle.
12)An air-standard Diesel cycle has a compression ratio of22
   and a cut-off ratio of 2.2. Determine thethermal efficiency of
   the cycle.
13)An air-standard Diesel engine has 1000 kJ/kg added asheat.
   At the beginning of the compression, thetemperature is
   20°C, and the pressure is 150 kPa. If thecompression ratio is
   20, determine the maximum pressure andtemperature in
   the cycle.
14)An ideal Stirling engine using air as the working fluid
    operates between temperature limits of300 and 2000 K.
    Determine the thermal efficiency of thecycle.
15) Consider an ideal Ericsson cycle with air as the working
    fluid executed in a steady-flow system.Air is at 270C and
    120 kPa at the beginning of theisothermal compression
    process, during which 150 kJ/kg of heatis rejected. Heat
    transfer to air occurs at 1200 K.Determine the thermal
    efficiency of the cycle and net workoutput per unit mass of
    air.
