Any GTPower users?

[my8950]

Starting to get into using GT Sim or GT Power, I'm curious if anyone on here is using it as well. Looking for any tips or helpful information you can give to someone who is just starting.

Thanks!

 

[j2bprometheus]

my8950-

I use GT Power. It does a good job of modeling if the user is an experienced user and knows something about engines. GT Power can easily generate reams of bogus results that would go unnoticed by people who don't know about engines.


GT Power does a good job modeling pulsations that happen in engines that I deal with.


But for many purposes, knowledge of the pulsations is unnecessary, so it is like using a sledgehammer to kill a fly.


GT Power has odd definitions of some things, like volumetric efficiency.

GT Power does a poor job of handling coolers.

Here are some things to watch out for, especially if someone else hands you an existing model:

A. Valve events based on cam angle rather than crank angle

B. controllers that do a poor job of controlling

C. multipliers for compressor efficiency, turbine efficiency, combustion efficiency, etc.

D. volumes of components that are ridiculus


j2bprometheus

 

[Lou Scannon]

like anything, garbage in = garbage out

I would never trust predictions from a necessarily complex simulation such as an engine model unless they were backed up by actual data bracketing the predicted case, or at least close to it.
In my experience, this tends to be an iterative process.
1. Develop model and tweak to validate against real data
2. With model, navigate operating point in direction of expected improvement
3. At a judiciously chosen point, check the model's prediction for the new operating point against new real data.
4. Refine/retweak model to get agreement with real data.
5. Recheck previously validated predictions to make sure they are still valid.
6. Repeat steps 2-6 until:
a. goal is reached
b. time or budget is exhausted

 

[TDIMeister]

Yup, GT-POWER/GT-DRIVE here.

 

[TDIMeister]

I guess I should follow up with my terse reply.

Agree that garbage in = garbage out.

I'd only add that simulation is nothing without calibration, validation and verification by bench testing of a physical model, whether it be a flow box or complete engine. In the absence of this, you can at best identify certain trends in the parameter changes you make in GT-POWER based on a sound base model, but not to conclusively establish absolutes.

 

[SomptingGuy]

To the OP: is this P&E or acoustics?

- Steve

 

[mkb58]

If using GT Power for acoustics, frequencies above 800Hz (upper limit dependent on engine model)could be iffy.
also pulsations after turbochargers may not correlate well with the engine.

Anyone has the same experience?

 

[Lou Scannon]

No, but my understanding is that Gamma Technologies is very interested in hearing about any model shortcomings experienced by users and will be keen to work through and resolve issues that you experience.

 

[my8950]

Hey, I lost track of this post....
This would be for engine modeling mainly, no acoustics at this time.
Thanks for the responses. It got busy for a while there, but I've got time that I am going to start putting back into this. I came across another engine sim program the other day that is quite a bit less extravagent. Desktop dyno....Its not really a simulation program, but still comes up with some sort of useful data for my case and background.
GTPower will produce better results I am sure, as well as supporting data...