Ci engine for heavy truck simulation

I am currently working on adapting a Simulink CI engine model initially designed for passenger vehicles to function for a heavy truck application. Specifically, the model includes components such as:

• CI Controller (Torque command and estimation)
• CI engine
• using the same components as those described in the ConVeh example from the Powertrain Blockset tutorial.

Could someone guide me on what specific parameters or components typically need to be adjusted or modified when scaling a passenger vehicle CI engine model up to represent accurately the dynamics and operational conditions of a heavy truck engine?

In particular, which parameters related to torque estimation, fuel injection, turbocharging, and air management should I prioritize adjusting to ensure realistic simulation results for heavy truck-sized engines?

Thank you!

Answer 1

[Vincent Hu]

hi newhere,

I think you are finding an CI engine model with suitable size for you truck by converting from an engine for a passenger car. So the following model and tool is helpful for you:

https://www.mathworks.com/help/releases/R2023a/autoblks/ug/ci-engine-dynamometer-reference-application.html

double click the button showed below:

then input your target displacement and cylinder number, and click resize, the tool will resize an engine with your target by conerting existing engine of pasenger car

then, you can find the model in the folders and use it in your vehicle model.

[newhere]

Hello, thank you for your reply.

I have used this approach to implement the model; however, it seems that the passenger car model (conveh one ) has certain limitations and cannot be directly adapted to a truck.

[Vincent Hu]

hi newhere,

I'm not sure what your problem is, but I guess the problem may be connect to driveline and tire blocks. Becasue the "Conventional Vehicle Example" was built with default blocks from Powertrain Blockset, which simulate some driveline dynamics and tire contact patch dynamics, and they are more complicated and need more effort to tune the model. You can try to tune:

• For truck, you need to increase the wheel intertia from ~0.8-2kg*m^2（passenger car） to ~5kg*m^2(light truck)/~9kg*m^2 (middle heavy truck)/~15kg*m^2(heavy truck)
• tune tire relaxation length, 0.2~1.5 to find a better value

• pay attention to the axle stiffness and damping, if possible, tune them to get better results.

if your use cases are not related to these dynamics and details, you can use the following link to find a leas fast model to run, which are easy to tune, but it's extended range car, not conventional car, you can use the libaray there or modify it yourself.

Extended Range Dual-Motor Electric Vehicle Model

thanks

Vincent Hu