View source for EVBEC

EVBEC stands for "Energy & Volume Based Estimator for Combustions", and is intended to calculate the muzzle velocity of [[combustion launcher]]s.
The latest version (V 1.2) can be downloaded from [[spudfiles]] right [

==Physics model==
EVBEC assumes that:
*Energy produced from combustion is directly porportional to chamber volume.
*The portion of this energy utilized in a launcher is directly derivable from the [[chamber:barrel ratio|Chamber to barrel ratio]].
*The [http://www.burntlatke.com/launch.html latke tests] are accurate.

From these assumptions, one can get the driving equation of EVBEC:
[math]v<sub>simulation</sub>=v<sub>test</sub>/SQRT((S<sub>test</sub>/S<sub>simulation</sub>)/(M<sub>test</sub>/M<sub>simulation</sub>))[/math]

Where:
*v is velocity
*S is chamber volume
*M is mass

Using this, the velocities are calculated for all the ratios tested by latke, and the proper ratio to use to find the velocity is indicated on a graph.

==limits of the physics model==
The physics model does not account for the following:
*Differing burn times
*Variations in efficiency caused by different projectile masses. (which is why the 1.5" data is "out there")
*Odd effects caused by launcher design (ie; breach restrictions).

Several of these problems are likely to be alleived when the results of some recent tests being carried out by pimpmann22 of the spudfiles forums are relesed.

==use==
Directions for use are provided in the documentation of the program.