The Influence of Application Usage Conditions in the Turbine Inlet Temperature

摘要

Turbochargers are used in a wide range of applications, duty cycles and different vehicle usage rates in whole world. As known, the exhaust gas temperature is still a challenge to the turbochargers manufactures once it has a considerable impact in the turbocharger durability and reliability. High temperatures can lead to thermal mechanical stress, which can cause material fatigue. Extensive works have been carried out by product and combustion engineers to guarantee that temperature limits are under acceptable values. However, there are other factors that are related to the application usage in the field that can contribute to the exhaust gas temperature increase. As known, service engineers have the difficult task of identifying the reason why some components used for years in different localities fail only in certain regions, fleet or applications. Trouble shootings are often a useful guide in the investigation, but are to generic most of the cases. The objective of this work is to analyze the factors which have the greatest impact on increasing the turbine inlet temperature due to the application conditions to better support service engineer's investigations. A design of experiment was done considering the influence of some common factors found in the field as the potential causes of engine overheating, which are vehicle load, air filter restriction and the turbocharger wastegate setting adjustment. During vehicle tests was possible to observe in which condition the engine presented the highest temperatures and identify what was the most influence parameter.