What is si engine? 

The otto-cycle engine in a Mercedes-Benz slk230 has a compression ratio of 8.8. What is the ideal efficiency of the engine?

Use:

Calculate the theoretical efficiency for an otto cycle engine with γ=1.40 and r=9.50.

A turboprop engine consists of a diffuser,
compressor, combustor, turbine, and nozzle. The
turbine drives a propeller as well as the
compressor. Air enters the diffuser with a
volumetric flow rate of 83.7 m3
/s at 40 kPa, 240 K,
and a velocity of 180 m/s, and decelerates
essentially to zero velocity. The compressor
pressure ratio is 10 and the compressor has an
isentropic efficiency of 85%. The turbine inlet
temperature is 1140 K, and its isentropic efficiency
is 85%. The turbine exit pressure is 50 kPa. Flow
through the diffuser and nozzle is isentropic. Using
an air-standard analysis, determine: (a) the power
delivered to the propeller, in MW. (b) the velocity at
the nozzle exit, in m/s. Neglect kinetic energy
except at the diffuser inlet and the nozzle exit