Internal Combustion (IC) Engine

Automotive Engine Design

It is an exciting time to be an automotive powertrain engineer, with many of the fundamental decisions that were made 50 or even 100 years being revisited, and many new options being explored thanks to the advent of new materials and advanced sensors and controls.

Fortunately, the ability to analytically evaluate candidate technologies and to fine-tune designs is keeping up with the need to explore new ideas.

A demonstration model is available to serve as a starting point for your explorations. While it is based on a four-stroke Otto cycle gasoline engine with 6 inline cylinders, the methods can be repurposed or extended to other cycles and configurations.

This FloCAD®-based model is built to explore short time scale events such as pressure waves within intake and exhaust runners, such that volumetric efficiencies and engine performance can be estimated. To do so, it models the transient actions of each of six cylinders independently through each stroke. Nonetheless, run times are fast enough (on the order of minutes) that parametric variations can be quickly explored. The focus of the problem is on the very short time‐scale events including pressure waves in the intake and exhaust runners. Details of flows, combustion, and heat transfer within the cylinder itself have been greatly simplified to preserve the focus on the air supply and exhaust systems.

Click here to download this sample from our support forum

This model was developed as a by‐product of an investigation of fast‐transient interactions within a turbocharged automotive engine.

Postprocessed Sinaps® Diagram showing temperatures and flows

Postprocessed FloCAD® diagram (sketch-pad mode) showing temperatures and flows

Pressure/flow profile for 720 degrees of crank rotation

Pressure/flow profile for 720 degrees of crank rotation (6000rpm, Cylinder #1)

Given heat loads and material properties, what is the temperature of a plate? That's how our tools work by default. But you can reverse the question too: What heat load is needed to heat the plate one hundred degrees in ten minutes? That "goal seeking" problem is one example of optimization. Another more complex example might be: What set of orifice sizes should I use at the exits of my heat exchangers to achieve even flows without any one component overheating? 

Optimization, combined with Thermal Desktop Measures (thermocouple models), can also be used to automate the adjustment of uncertainties to better match available test data or CFD predictions.

Some uncertainties just can't be adjusted away. Or maybe you don't yet have test data and need to understand how tolerances and environmental variations affect your design.

All of the above tasks are part of our Advanced Design Modules. Come learn about them in a series of upcoming webinars:

All three webinars are at 1pm PT, 4pm ET.