Study On The Leakage Of Non-Contacting Finger Seal And The Influence Of Thermal Deformation On It

Non-contacting finger seal is a kind of advanced seal which is developed to solve the inevitable wear problem of contacting seals.It's lower leakage rate and the potential of infinite life make it adapt a more severe working condition.Which makes non-contacting finger possible to have a wider range of applications.However.The problem of pneumatic friction caused by rotor with high rotational speed and structural deformation under high temperature environment brings the challenges to the application of non-contacting finger seal.Based on extensive literature.A structure of finger seal in public is used to simulate the characteristics of flow,deformation and leakage of non-contacting finger seal.The results are following:By using the method of conjugate heat transfer.The basic form of leakage flow of non-contacting finger seal is studied to analysis the impact of rotor speed,axial pressure difference and flow viscosity.The results show that: the leakage flow exists the diversion of circumference direction because of the rotational rotor;the rotational rotor causes the high local temperature area and increases the average temperature and pressure of pad;Axial pressure difference is the main driving force for leakage and makes a significant effect on pressure distribution.Viscosity causes a severe condition of pneumatic friction so that generate more heat.The Time-Hardening equation is imported to consider the creep effect on pad and to analysis the deformation characteristics of pad under different working conditions.The impact of temperature,rotational speed,axial pressure difference,viscosity and material parameters on deformation is studied.The results show that: the temperature,rotational speed and axial pressure difference make a significant impact on deformation of pad with positive correlation.The viscosity and material parameters will effect the deformation to some extent.Creep basically does not effect the deformation.A method of two-way fluid-solid coupling is put forward to solve the problem of mesh deformation that causes the end of simulation based on deformation structure.The effect of temperature,rotor speed,axial pressure difference,viscosity and material parameters on leakage is studied.The results show that: the temperature,rotational speed and axial pressure differential make a significant impact on leakage of pad with positive correlation.The viscosity and material parameters will effect the leakage to some extent.Creep basically does not effect the leakage.