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Old 05-03-2009, 10:30 PM   #122 (permalink)
Ernie Rogers
Ernie Rogers
 
Join Date: Feb 2008
Location: Pleasant Grove, Utah
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Quote:
Originally Posted by Jim Bullis View Post
Yah you do need the program because it is not about 3/7. Ernie's programs will include the efficiency of making electricity in some form or other.
Sorry, Jim,

The program as it is now just requires an input number for efficiency--one number for the engine and a separate one for the electric system.

But a nice thing about using a computer program is that you can make the calculation as complicated as you want and the program does the work. For example, I have a specialized fuel economy program for by VW that includes an engine model. It calculates the engine efficiency as a function of power and RPM, using a fit to experimental data. With this program, I can evaluate the impact of changing the gear ratio in 5th gear. (The possible improvement this way is huge, since the engine develops plenty of torque and hits peak efficiency when slowed down to about 1700 RPM.)

Ernie Rogers
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