Analysis Of The Rod-fastening Rotor’s Distortion Similarity Problem And Research On A Characteristic Prediction Method

ABSTRACT:The gas turbine rod-fastening rotor’s prototype and completely similarity model’s similarity was studied, and the distortion similarity between the prototype and the distortion models was also analyzed. Furthermore, a characteristic prediction method based on a distortion rotor model was proposed in the paper. The main research contents and results read as follows:Firstly, the rod-fastening rotor’s prototype and model’s completely similarity criteria were derived by using dimensional analysis method, and corresponding similarity index formula were obtained. Considering contacts between disks, the rod-fastening rotor’s finite element model was established. Similarity analysis between the prototype and model was conducted based on the rod-fastening rotor’s finite element model;.Secondly, the rod-fastening rotor’s distortion characteristics was analyzed, and the distortion criterion of the model was obtained; Similar parameter sensitivity was proposed to measure the change amount of the test result caused by the parameters’ change amount; The distortion rotor model’s single parameter compensation methods and the multi-parameter compensation method were proposed respectively for different types of distortion model, which perfects distortion model compensation theory. Different distortion models’and corresponding compensation models’ finite elements were established. By taking the similarity of rotor’s modal frequency as examples, characteristics of distortion models’, compensation models’and completely similarity modals’frequency curve were studied. The theoretical analysis were verified by numerical analysis.Finally, single distortion parameter rotor model’s and multi-distortion parameter rotor model’s prediction coefficient expression were derived and the corresponding prediction coefficients’ and distortion similarity constant’s function expression were obtained. Characteristics prediction methods based on a single distortion parameter rotor model and a multi-distortion parameter rotor model were proposed, which makes the test results of a distortion model can predict the real characteristic of its prototypes.