A Research on Waste-Gated Turbine Performance Under Unsteady Flow Condition

摘要: Turbochargers are key components of engine air-paths that must be carefully considered during the development process. The combination fluid, mechanical, and thermal phenomenon make turbocharger a highly dynamic nonlinear modeling challenge. aim this study is to quantify response system across frequency spectrum from 0.003 Hz 500 Hz, i.e., for exhaust gas pulsation in steady state, load steps, cold start drive cycles, validate assumption quasi-steady assumptions particular problems. A waste-gated turbine was modeled using dual orifice approach, lumped capacitance heat transfer model, novel, physics-based pneumatic actuator mechanism model. Each submodel has been validated individually against experimental measurements. inlet pressure temperature waste-gate were perturbed full range both simultaneously separate numerical investigations. responses housing temperature, rotor speed, opening, mass flow, temperatures/pressures all investigated. flow parameter exhibits significant behavior above 100 illustrating invalid range. showed below 10 while mechanical inertia attenuated fluctuations shaft speed frequencies between 0.1 Hz. meant variations supressed at 0.01 results have used illustrate importance model parameters three transient simulation scenarios (cold start, step, pulsating flow).