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In: Mechanical Engineering

An ideal Otto engine has a compression ratio of 10 and uses air as the working...

An ideal Otto engine has a compression ratio of 10 and uses air as the working fluid. The state of air at the beginning of the compression process is 100 kPa and 27 0C. The maximum temperature in the cycle is 2100K. (R=0.287 for air) (using variable specific heat)

  1. Draw the P-v diagram of the Otto cycle
  2. Determine the specific internal energies at the beginning and the end of the compression,
  3. Determine the specific internal energies before and after the expansion
  4. Determine the specific heat input, heat rejection and net-work output.
  5. Determine the thermal efficiency.
  6. If the amount of air in one cylinder at the beginning of compression is 500 cm3, how much power can the engine deliver for an 8 cylinder engine running at 2000rpm?

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