Study On Matching Of A Turbocharger And Its Noise For483Diesel Engine

With the demand of automobile energy-saving and emission reduction is becoming more and more strict, passenger car’s dieselization has become an important trend. In order to make the cars meet the requirements of high efficiency, energy saving, environmental protection and comfort, research on optimal matching and noise on the turbocharger and diesel engine has the important practical significance.Based on a483diesel that is equipped in a SUV vehicle produced by one company, using the method of combining theory with test to match the turbocharger, and test on the noise about the vehicle carrying a turbocharger, thus provide the basis for the development and application of this kind of turbocharged diesel engine.The main contents and conclusions of this dissertation are summarized as follows:(l)According to the technical parameters of483diesel engine, the ordinary bypass bleed type exhaust turbocharger was chosen as matching model through the turbocharger needing analysis.(2)The calculation results show that about the compressor end, on external characteristic, when engine is1000rpm, pressure ratio reached1.26, and flow rate0.021kg/s; when engine is3800rpm, the pressure ratio reached the highest value2.69, while flow rate is0.153kg/s. About the turbine end, for the rated point, the pressure front of turbine is397.66kPa, manifold pressure is248.71kPa; for the commonly used speed, the pressure difference is less than50kPa, far less than the recommended safe pressure difference limit100kPa, therefore, the reliability of turbocharger matching scheme can be guaranteed.(3)According to the calculation, a turbocharger was selected from the characteristic data library about the compressor and turbine production in Hunan Tianyan Machinery Co. Ltd., selected compressor was named JP44F-4472, while the turbine was JP44F-3580.(4)The united matching test between selected compressor, turbine and483diesel engine was carried out, which verify the rationality of matching results; and by adjusting the pre-tightening force of the execution, the influence on the performance of joint test caused by pre-tightening force was studied. The results show that when preload pressure is169kPa, and the engine speed is under4000rpm. Considering the power output and fuel consumption rate, the matching turbocharger can meet the developing requirements of483diesel engine. In order to make the exhaust temperature and fuel consumption rate meet the requirements, it’s need to change the actuator’s preload pressure as174kPa when the engine speed is4000rpm.(5)Applied two turbocharged diesel engines carried by a vehicle, the turbocharger noise test was conducted. The results show that the two test turbochargers exist a risk of producing first-order noise. So as to determine whether there is this kind of noise, the subjective evaluation and objective basis for the turbocharged vehicle NVH were presented, which confirms that the acoustic performance of designed JP44F turbocharger can meet customer’s requirements.