Research On Helicopter High Contact Ratio Planetary Gear Train Specific Power Optimization Based On The Theory Of Interval Mathematics

Rotor helicopter, referred to as helicopter, as one of the important traffic inventions in the history of human science and technology, is widely used in military transportation, patrol, rescue and disaster relief,etc.fields. Helicopter main reducer as the main power transmission part of its drive system, its weight and efficiency affect the helicopter engine load, flight range and maneuverability directly, so compared to other gear reducer, the helicopter main gear reducer has higher request to the weight efficiency, volume and reliability, there is a need to make the structure design for the small volume and high reliability main reducer and make the specific power(the ratio of the transmitted power and weight)optimization research for the gear transmission system of the main reducer.First of all, the thesis analyzes the structure layout of helicopter main gear reducer, in view of its special performance requirements; mainly consider the weight, reliability, cost and other technical indicators of object design, puts forward a structure scheme that conforms to the helicopter-hollow shaft type planetary gear train of main reducer with bearing integration technology; and according to the helicopter main reducer gear ratio distribution experience both at home and abroad, using entropy method calculate transmission ratio distribution. Based on the traditional design method of gear, estimate the sun gear diameter according to the hollow sun gear axle strength, then get the design parameters of the straight tooth planetary gear train before optimization.Second, establish the interval multi-objective specific power optimization objective function and constraint functions of main reducer straight tooth planetary gear train with the uncertain parameters of mesh density, friction coefficient, using ordinal dominant and interval analysis method, convert the objective function containing interval parameter to the objective function containing definite parameters, and transform the multi-objective function optimization problem into the single objective optimization problem through the unified objective function method. Eventually get the optimal parameter interval of objective function and the optimal values of design variables of the HCR planetary gear train using the finincon toolbox of MATLAB software, then compare and analyze the results of the planetary gear train efficiency,weight and gear strength before and after optimization,the results show that the superiority of the interval multi-objective optimization algorithm. Finally, make the noise and efficiency test for planetary gear train before and after the optimization using electric closed gear test rig, under different input speed and load conditions compare the efficiency of the planetary gear train and the noise spectrum in cabinet under the similar background noise before and after the optimization, then design and manufacture the sound insulation cover that applies in noise test-bed in this article, and verify its effectiveness for noise isolation in the theory.