STUDY AND CONTROL OF UNSTEADY FLOW IN THE TURBOCHARGER OF DIESEL ENGINES

摘要

The unsteady flow due to compressor rotating stall in the turbocharged diesel engine has been investigated in this paper. Controllers with different ideas have been modeled to widen the region of stable operation of the compressor, and thus, improve diesel engine performance characteristics. The models include nine states, which represents the different subsystem components: air filter, intake manifold, intercooler, exhaust manifold, exhaust system, exhaust gas recirculation, compressor and turbine. Effects of each system machinery on the diesel engine performance characteristics have been investigated. The second part, investigates the compressor surge phenomenon, it's hazardous on the diesel engine stability and range of stable flow operation. Also, different techniques to suppress or for controlling the surge phenomenon and increase of the range of stable operation of the compressor were carried out. These techniques are the changes of engine intake manifold volume, throttle gain, auxiliary plenum, closed coupled valve and bleed valves. Comparisons of the present theoretical results with the available previous experimental and theoretical results were carried out.