Engine Type
Compression Ratio
Heat Engine Cycle  
Bastian Cycle (TRE)
Otto Cycle (ICE)
The Otto Cycle Efficiency

An Otto Cycle is an idealized heat engine cycle that consists of
a compression phase followed by an ignition phase this is
initiated by a spark plug or other type of igniter, followed by
an expansion phase, and finally an exhaust phase.  These
phases are the same as those utilized by the TRE, which
makes this a good Method for analysing the TRE.  The
assumptions and simplifications employed in the Carnot Cycle
Efficiency Analysis, namely isentropic compression and
expansion, isochoric energy addition, and the working fluid,
air, is an ideal gas, are also employed in the Otto Cycle
Analysis.  The goal of this analysis is to calculate the ideal
efficiency of a system based on a single factor, in this case
normalized volume ratio or compression ratio, which will
facilitate the comparison of different heat engines.  The Cycle
efficiency of the TRE was determined by calculating the
average efficiency obtained from the injection port to the
exhaust chamber ports.
Table 2:  Otto Cycle Efficiency of the TRE and ICE
Click here to view the Compression Ratio Table
Engine Type
Fuel Usage
Mechanical Efficiency
Bastian Cycle (TRE)
1 Gallon
Estimate is 30%
Otto Cycle (ICE)
2.5 - 3 Gallons
Actual 12% - 15%
Table 3: Mechanical Efficiency Comparison for your Car