The VeSyMA – Engines library is capable of modelling both Spark Ignition and Compression Ignition engines and supports two different levels of fidelity for the models.
The Mean Value models predict the cycle averaged intake and exhaust flows, emissions and torque. The Crank Angle Resolved models predicts the complete cyclic intake and exhaust flows and torque using either a weibe or predictive combustion model.
The library covers the air-path, fuel system, cooling system, lubrication and mechanics of the engine allowing the full system behaviour to be studied and investigated.
- Control system development using detailed physical models of internal combustion engines.
- Supports spark ignition and compression ignition engines as mean-value or crank-angle resolved models.
- Includes turbocharger and supercharger models for forced induction engines.
- Captures the full transient response of the engine (air-flow, Multi-body and 1-D mechanics and thermal effects).
- In-vehicle NVH and performance analysis when coupled to the Powertrain and Vehicle Dynamics libraries.
- Physical fault insertion.
- Reduction of dyno test time.
- Repeatable virtual test conditions.
- Real-time capability.
- Animation is built-in to the models.
- Aftertreatment.
The Mean Value version predicts the cycle averaged air flow and torque produced by the engine.
The cylinder mass flow rates are calculated through an equation based approach allowing the engine capacity to be scaled within reasonable limits. This enables downsizing studies to be carried out using the library.
The combustion and emissions modelling is map based using manifold pressure and engine speed as the primary inputs to the maps with further corrections for spark timing and afr.
This version of the Engine library is particularly suited to driveability analysis where the effect of throttle transients on the driveline behaviour are investigated. In addition, this version of the library is also suited to catalyst light-off investigations.
The Crank Angle Resolved version predicts the cyclic variations for air flow and torque. This is an extension to the Mean Value version of the library.
The combustion heat release is modelled though a two-zone predictive model or a Wiebe model with table based coefficients. The table defines the Wiebe model coefficients at different engine speeds, loads and air-fuel ratios. Both Compression and Spark ignition heat release models are available. Port fuel and direct injection are also supported.
The flow though the engine block is dictated by the valve geometry and opening characteristics and the piston-cylinder assembly model. Valve and spark timing effects on the fluid dynamics and combustion model mean that the engine performance can be investigated using this version of the library.
This version of the Engine library is particularly suited to driveline NVH analysis, mount excitations, cranking and detailed friction modelling.
Technical Papers
- Dempsey, M., Picarelli A., Investigating the MultiBody Dynamics of the Complete Powertrain System. Como, Italy: Proceedings 7th Modelica Conference, 2009.
- Dempsey, M., Fish, G., Picarelli, A., Using Modelica models for Driver-in-the-loop simulators.Munich, Germany: Proceedings 9th Modelica Conference, 2012.
- Dempsey, M., Roberts, N., Predicting the launch feel of automatic and dual clutch transmissions. Munich, Germany: Proceedings 9th Modelica Conference, 2012.
- Picarelli, A., Dempsey, M., Simulating the complete 2014 hybrid electric Formula 1 cars. Video. London: IET HEVC 2014.
- Picarelli, A., Galindo, E., Diaz, G., Thermal shock testing for Engines in Dymola. Lund, Sweden: Proceedings 10th Modelica Conference, 2017.
- Gallarotti, M., Picarelli, A., Dempsey, M., Investigating the Effect of a Sonic Restrictor in the Intake of an Engine. Prague, Czech Republic: Proceedings 12th Modelica Conference, 2017.