Engine simulator

[x_atlas0]

Hello, everybody.

I thought some of you may be interested in this little tool I made for a project a few years ago. It is an Otto cycle based engine simulator. You enter in the parameters of the engine you want to simulate, and it will produce a dyno plot, along with max pressure, max temp, and fuel consumption rates. You can even change the intake parameters, like input temp and pressure.

It is a very simple model, as it doesn't even take into account things like flame speed, cam timing, air speed, resonance, or fluidic realities. However, I added in a few basic correction factors to give it a reasonable result from ~2000 RPM onward. Feel free to tweak it however you want. Places that could use some correction are mainly the need for timing, both spark and valve. Right now, it is pretty much an idealized version, hence the need for the correction factors.

Hope it helps some people with their engine builds.

Here is the tool:
http://www.prism.gatech.edu/~gtg982h/hydrogen.xls

All the control blocks are between AO and BC.

Let me know what you think.

 

[Bert-Ola]

All the control blocks are between AO and BC.

Let me know what you think.

Hello

I've downloaded your file and are trying to figure it out.

The input cells for variables I found are:
AR44, AS39, AU39, AU44, AX44, AY48, AZ41.

And fixed parameters in:
Row G

And values not currently not in use:
AS1->BA9

Have I got it right so far?

 

[x_atlas0]

Yep, that is almost all correct. The AY48 is really AY49. I made it so you can change the fuel used in the current calculations by moving which cell is replicated in AY49. The values in AY47 and 48 are the lower heating values, in kJ/kg.

The stuff in AS1->BA9 relate to linear approximations of the performance of the Eaton M90 supercharger. Part of the project was designing a system using the M90 on the M30 engine, so I made the models for power loss, extra air intake, that whole jazz. Right now, though, it is a somewhat deactivated section, since it isn't boosted in the model. You can change that by putting in a new value in AZ41, which is currently set for atmospheric.

Sorry it is hard to follow, I made it just for the project, and never intended to use it again, so it is pretty rough around the edges. It is actually a lot better than it was when I made it for the project, all the inputs were hardcoded until I made them dynamic a few weeks ago.