Research Of Vehicle Turbocharger Rotor Dynamics Characteristics And The Unbalance Response

The turbocharger is the use of exhaust emissions from engine to drive a turbine to rotate, so as to drive the impeller rotating air end, will be more air to the cylinders,achieve the goal of pressurization, has the advantages of energy conservation and emissions reduction and increase engine power. Is the most critical of the turbocharger rotor of the turbocharger parts, belongs to the typical double cantilever rotor structure, complex vibration characteristics.Because of fuel combustion engine produces in the process of colloid and resin dope, uneven deposition on the turbine blades and create a dynamic imbalance, makes the turbocharger vibration under high-speed increase and destroy the parts fit clearance, scratch and damage to the bearing surface, which resulted in increased engine power loss, even cause the malignant accident such as destruction of the turbocharger, seriously affect the overall comprehensive performance and quality.In this paper, through the simulation calculation and experimental analysis method of combining the study of rotor unbalance response law. At the same time in order to solve this kind of light weight,high speed rotor of the turbocharger, asymmetric rotor structure in actual test is difficult to get to the problem of the modal frequency of the modal frequency test method this paper carried out the research.The main study of this paper include:1) Using Dy Ro Be S simulation software, the rotor of the turbocharger components based on the actual drawing size of compressed air the impeller, turbine impeller, shaft, thrust plate, floating ring bearing, hollow cylindrical model.Carried out the critical speed and vibration mode analysis and the turbine side and air side unbalance response analysis under steady state synchronization2) To the simulation validated the law, on the basis of the existing experimental condition, the independent design structures, the summary of the turbocharger test bench, the use of air compressor high pressure air driver can make the rotor of the turbocharger speed has reached around 25000 RPM, can be used to simulate the turbocharger running at low speed. Through the construction of the test bench for behind the imbalance based on test analysis.3) On the basis of the existing test equipment, and unbalanced for turbocharger rotor was carried out by research, finally concluded that the increase in air side blade vibration response amplitude is much bigger than on the turbine side blade, which iscompressed air for unbalance response than the impeller turbine impeller be sensitive.The simulation rule to verify.