One of the more visible tasks when designing a turbocharger is the optimized design for a compressor and a turbine. The ultimate measure of a successful turbocharger design, however, is how well it works with a specific engine at various operating conditions. Final design decisions must be based on the engine-turbocharger system as a whole, rather than only on the individual component performance.
This paper describes the effort to develop an integrated design system which allows the user to design and optimize a turbocharger on a system level. With the basic engine parameters specified, along with simple models for other commonly used components, such as the Exhaust Gas Recirculation (EGR), wastegate, and intercooler, the program may be linked to two powerful meanline programs that can handle the fast iterations of the design and analysis of a compressor and a turbine. The output is either a new compressor or turbine that best matches the operation of the engine or the performance of an existing turbocharger at a specific engine operating condition.
A case study is presented where the program is applied in a real-life design situation to fit a new turbocharger for a large locomotive 18-cylinder diesel engine. The tool is extensively used in guiding the selection of the turbocharger and in the simulation of the overall system performance. The test data from the new design show close agreement with the simulation results, as well as an improvement over the original design.
