GT Model for Passive Flapper Exhaust Valve

Passive valves are common acoustic tuning devices for auto exhaust systems. A new mathematical algorithm based on fundamental physics is presented for simulating an exhaust flapper valve. It is programmed into the popular GT Power simulation software as a model component. Algorithm performance is evaluated for predicting pressure drop of an exhaust flapper valve.

The model and software predict pressure and flow for steady state flow through the valve at elevated temperatures. Flow bench simulations and experiments are done. Hot flow results are compared to determine performance. The algorithm model is also compared to a reed valve component available in the standard GT library. A comparison of predictions and measurements show,

1. 1.
   The error of an “Off the shelf” software component is on the order of 10%.
2. 2.
   The new algorithm's error is on the order of 2%.