FAST RUNNING MODEL in GT-POWER USING FRM BUILDER

FRM ( FAST RUNNING MODEL ) :[Tutorial : 9]

Introduction:

FRMs execute much more rapidly than the typical detailed GT-POWER engine model, and are ideal for integrating with other vehicle systems where an accurate and predictive engine plant model is desired and where computational speed is critical. FRMs adapt to changing conditions (e.g. valve timing, spark/injection timing, turbo lag, external temperature, altitude, cooling system conditions, etc.) without the need to apply non-physical correction factors. Whether studying changes to ambient conditions, or simulating events that are heavily transient in nature, FRMs will maintain the predictive capabilities of a detailed engine model while allowing for the fast computational speeds that are expected when performing drive cycle analysis and other transient-focused simulations.

Some examples of applications that are ideal for FRMs are:

• ECU Modeling (including HiL) – where a fast-running and transient-capable engine model is essential for optimizing ECU strategy
• Engine + Drivetrain/Vehicle – where accurate torque pulsations are key for optimizing drivetrain design and strategy
• Vehicle Thermal Management modeling, where the engine provides the heat to the cooling system, and the cooling system behavior feeds back into the engine performance predictions (great for simulating off-ambient conditions)
• And many more.

In addition to covering the complete conversion process of going from a detailed engine model into an FRM, this class will also cover special considerations that may come up depending on the intended use of the FRM. An agenda of this class is below:

1. Brief introductions to FRMs and their applications
2. Converting a Detailed GT-POWER model into an FRM
   1. Reviewing the baseline detailed model
   2. Simplifying each subsystem of the detailed model
   3. Additional modifications for achieving even faster run times
3. Discussion of application-specific considerations when making an FRM
   1. Real-Time and Hardware-in-the-Loop modeling
   2. Engine Cooling and Heat Rejection
   3. Aftertreatment modeling
4. Discussion of Transient Simulations using GT-SUITE (including Controls)

FRM MODEL:

* The basic difference is nothing but the detailed volumes are reduced to a single big volume

* And the discretization length can be modified and reduced to a certain number , so that the number of calculations can be reduced

* Also the time step size is increased to reduce the calculations

FRM BUILDER:

As per the given dimensions

This is the FRM subassemblies;

This is the diesel engine configuration , where the major connections are made into a single assembly to make it into a FRM.

There are totally 25 cases are here;

And all the cases are shown and simulated;

The compressor maps are generated and the operating points are calibrated

and also the controllers are converging as the target values are reaching.

This indicates the sample case 2 in all the cases

This is how the parameter varies in the FRM when comparing it to the detailed models

CONCLUSION:

Thus the FRM models are in high fidelity with the real models and hence it should be very concise about its time , as it has to send and receive the signals during the engine simulation and this FRM plays a major role in developing the HiL systems to calibrate the engine models and also to develop the control strategies for engines.