Turbocharger Performance Maps Building Using a Hot Gas Test Stand

Abstract

This work presents the experimental methodology used in turbochargers tests using a hot gas test stand. The test consists in recording the characteristic curves of the turbochargers, known as flow maps or performance maps. A tubular combustion chamber, designed to operate burning gaseous fuels, is used to drive the set. By using a hot gas generator it’s possible to simulate the real operational condition of the turbine. The experimental configuration allows reproducing the self-sustained turbocharger operation. The test stand instrumentation is based on virtual instrumentation, where acquisition of the sensors and control are made by computer. For the performance maps obtainment, the experimental data are treated through an empirical model based in a quadratic equation involving two variables, mass flow rate and rotational speed. The results present the performance and efficiency maps for the APL-240 Master Power turbocharger, used in commercial heavy trucks. With the results is made a comparison between the experimental maps with the maps gotten through a semi-empirical model based in modified Euler equation. The maximum deviation for compressor and turbine semi-empirical pressure ratios are respectively 8% and 14% in relation to the experimental data.

Modelo matemático de un plenum para obtener las características dinámicas del flujo másico de un turbocargador

“…Para hallar el comportamiento del flujo másico que absorbe el compresor del medio ambiente respecto a su carga y abstraerlo en un modelo matemático, se debe involucrar el comportamiento interno de las características físicas del rodete del compresor, teniendo en cuenta su entrada y salida del flujo cuando este recorre el rodete. Este estado genera diversos cambios de energía en la configuración de los álabes del rodete del compresor [33]. Para lograr este fin se utiliza un elemento denominado plenum, que tiene como propósito el de permitir el análisis integral de este con la geometría interna del compresor.…”