Numerical And Experimental Study On Damping Characteristics Of Squeeze Film Damper For Turboshaft Engine

SFD, which has many advantages such as compact structure and significantdamping effect, is widely used in aircraft engines, marine gas turbine and industrialdeep hole machining. Parameter design for squeeze film damper in practical mostdepend on trial and error method, which need to design multiple squeeze film dampersuntil one of them meet the actual needs. This approach is low-efficiency and need formore tests and experiments. In this paper, the commercial numerical software Fluent isused to simulate the pressure distribution and analysis oil film force of squeeze filmdamper and calculate the damping factor. The influence of the damper length, gapparameters on the damping factor is discussed combined with experimental analysis.The main contents are as follows:1)The geometry of squeeze film damper is created in this paper, as well as meshingand boundary conditions. Grid-independent and time step independent is verified toensure the accuracy of numerical calculation. Reynolds number is calculated to confirmthe stream state. Other works including moving boundary preparation procedures andcavitation definition is also done in this paper.2)Comparison with the experimental results of Advanced Rotor Dynamics show thatthe result of Fluent simulation and the calculated damping factor is accurate. The papersimultaneous compared film pressure distribution and the force of the oil film with andwithout cavitation. Model results show that the use of cavitation to some extent reducethe magnitude of the oil film force and Makes the oil film force waveform appears acertain degree of lag.3)The influence of the oil clearance, damper length and frequency of the excitingforce on the damping effect is studied. The conclusion that simulation result containedcavitation model are generally between semi-and full-film root of the single-phaseReynolds equation is concluded.4) Experimental results show that if oil pressure supply is low, the results ofnumerical simulation are in good agreement with the experimental results. Numericalsimulation results can be used as reference experiments and design. When there is ahigh pressure oil supply, or other measures to suppress cavitation, the numerical resultswith experimental results deviations greatly. In that case non-cavitation model results ismore accurate.