Temperature Estimation of Turbocharger Working Fluids and Walls under Different Engine Loads and Heat Transfer Conditions
2013 (English)In: SAE Technical Papers, 2013Conference paper (Refereed)
Turbocharger performance maps, which are used in engine simulations, are usually measured on a gas-stand where the temperatures distributions on the turbocharger walls are entirely different from that under real engine operation. This should be taken into account in the simulation of a turbocharged engine. Dissimilar wall temperatures of turbochargers give different air temperature after the compressor and different exhaust gas temperature after the turbine at a same load point. The efficiencies are consequently affected. This can lead to deviations between the simulated and measured outlet temperatures of the turbocharger turbine and compressor. This deviation is larger during a transient load step because the temperatures of turbocharger walls change slowly due to the thermal inertia. Therefore, it is important to predict the temperatures of turbocharger walls and the outlet temperatures of the turbocharger working fluids in a turbocharged engine simulation.
In the work described in this paper, a water-oil-cooled turbocharger was extensively instrumented with several thermocouples on reachable walls. The turbocharger was installed on a 2-liter gasoline engine that was run under different loads and different heat transfer conditions on the turbocharger by using insulators, an extra cooling fan, radiation shields and water-cooling settings. The turbine inlet temperature varied between 550 and 850 °C at different engine loads.
The results of this study show that the temperatures of turbocharger walls are predictable from the experiment. They are dependent on the load point and the heat transfer condition of the turbocharger. The heat transfer condition of an on-engine turbocharger could be defined by the turbine inlet temperature, ambient temperature, oil heat flux, water heat flux and the velocity of the air around the turbocharger. Thus, defining the heat transfer condition and rotational speed of the turbocharger provides temperatures predictions of the turbocharger walls and the working fluids. This prediction enables increased precision in engine simulation for future work in transient operation.
Place, publisher, year, edition, pages
, SAE Technical Papers, ISSN 0148-7191
Turbocharger, Heat transfer, Temperature estimation
Vehicle Engineering Energy Engineering Fluid Mechanics and Acoustics Applied Mechanics
IdentifiersURN: urn:nbn:se:kth:diva-127531DOI: 10.4271/2013-24-0123ScopusID: 2-s2.0-84890375940OAI: oai:DiVA.org:kth-127531DiVA: diva2:644505
11th International Conference on Engines and Vehicles, ICE 2013; Capri, Naples, Italy, 15-19 September 2013
FunderSwedish Energy Agency
QC 201401092013-08-302013-08-302014-10-01Bibliographically approved