It is important for vehicle concept planning to estimate fuel economy and the influence of vehicle vibration using virtual engine specifications and a virtual vehicle frame. In our former study, we showed the 1D physical power plant model with electrical starter, battery that can predict combustion transient torque, combustion heat energy and fuel efficiency. The simulation result agreed with measured data. For idling stop system, the noise and vibration during start up is important factor for salability of the vehicle.
In this paper, as an application of the 1D physical power plant model (engine model), we will show the result of analysis that is starter shaft resonance and the effect on the engine mount vibration of restarting from idle stop.
First, an engine model for 3.5L 6cyl NA engine was developed by energy-based model using VHDL-AMS. Here, VHDL-AMS is modeling language registered in IEC international standard (IEC61691-6) to realize multi physics on 1D simulation. The modeling language supports electrical, magnetic, thermal, mechanical, fluidic and compressive fluidic domain. The model was modeled in house by fully VHDL-AMS and validated.
Next, Engine Inertia Matrix (EIM) model was developed by inertia matrix on MATLAB SIMULINK. MATLAB is suitable for matrix calculation. The engine model provided combustion pressure and crank angle to Engine Inertia Matrix Model, which represented engine components by location using matrix. This engine structural model processed combustion pressure from physical engine model to vibration force.
We found that the simulation results for engine mount vibration agreed well with measured data.