The Design And Assemblage Of An Experiment Rig For Steam Induced Vibration Investment

Sealing arrangements, especially labyrinth seal, has always played an importantrole on reducing the leakage and increasing the efficiency of steam turbines. However,with the development of the steam turbine design, the operating parameters of steamturbine such as steam pressure and temperature has been increased all the time, whichbrings up a problem that the steam induced vibration has a more serious influence onsteam turbines. This problem has threatened the safety and stability of steam turbines.The number of impact factors for the vibration is large. In addition, the influence ofan impact factor on the vibration may become different as other factors change. Theinfluence on the vibration of some factors is still unknown. Thus the original reasonsfor steam induced vibrationarecomplicated, which makes the vibration stilluncontrolled. As a result, solving the steam induced vibration problems mainly dependson experience and has a bad result sometimes.To find the influences of impact factors on vibration forces for different conditions,a steam induced vibration test system is designed, also the equipment selection, partsmanufacturing, assemblingand debugging have been finished. The designed inletpressure, the pressure ratio, the rotating speed and the vibration frequency are alladjustable within certain limits.The steam induced vibration test systemhas been established. The Dynamiccoefficients can be calculated with the measurement of the vibration acceleration,displacement and forces, after which influences of different factors can be find. Theexperimental research will offer useful experimental data for the vibration problems.Also,the experiment system can be used for research on dynamic coefficients ofdifferent labyrinth seals, whichshows the stability for different seals and offersreferences of how to handle the vibration problems.Except for the experiment rig, a series of numerical calculations is conducted. Thedynamic coefficients as well as the leakage are calculated with seal clearances of0.2mm,0.3mm,0.4mm, and0.8mm.The results canbe used for deeper analysis through the flowin seal cavities, which will be compared with the experiment data and be a preparationfor the further investigation on steam induced vibration. Because of the construction progress of the experiment rig, the large scale ofexperiments has not been carried out, which will be conducted in the coming researchwork. In addition, problems will be find and experience will be got as the experimentalresearch goes deep, which will bring refitment on the experiment rig. After refitment,the possible range of the experiment factors will be larger and more experiment datawill be got to help with the further vibration research.