Study On General Structure Of Rear Turbine Of Unmanned Vehicle Power System

With the advantages of unmanned operation,digitization and informatization in the ground war,unmanned vehicles can be applied to some complex battlefields,such as nuclear radiation,explosion and biochemistry by loading different equipment.At the same time,it can also load conventional combat weapons to directly involve in ground combat to reduce casualties.Power system is an important part of unmanned vehicles.At present,batteries,piston engines,or hybrid power technology are used by most of the unmanned vehicle power systems.Compared with the piston engine,the turbine engine has the advantages of light weight,large ratio of power to weight,large power volume ratio,small vibration,small volume,easy start and maintenance.Under the same conditions,the hybrid electric drive system,on the application of turbine engines to drive the generator in the unmanned vehicle,can reduce the quality of unmanned vehicle power system and carry more fuel,which contributes to a substantial increase in vehicle voyage.In this paper,the GTCP131-9D auxiliary power unit of large-scale aircraft is used,and the load components are removed to only retain the core engine of it.Combined with the existing generators and the design of the rear turbine,the three together constitute a turbine generator,which provides a more lightweight and large voyage power system for unmanned vehicles.The specific research contents of the rear turbine structure design are as follows:Therefore,the above-mentioned calculated overall performance parameters are optimized so that the unmanned vehicles have better Economy,and with the selected auxiliary power device parameters can be a good match.1)Design of the overall performance of the rear turbine design point.Based on the basic assumptions,the parameters of the thermodynamic characteristics of the rear turbine engine are analyzed systematically and the thermodynamic cycle of the turbine engine is calculated by the variable specific heat calculation method.The overall performance of the rear turbine design program is written by the C + + language,and then the parameters are general performance parameters of the rear turbine are worked out.If it is directly applied to unmanned vehicles,there will be a problem that the power consumption rate of the rear turbine unit is high and the economy is poor.Therefore,the above calculated general performance parameters are optimized so that the unmanned vehicles have better economy and can well match with the selected auxiliary power unit parameters.2)Aerodynamic structure design of rear turbine design point.According to the cascade theory and velocity triangular theory,the leaf design process of the rear turbine stator and rotor is calculated,and the aerodynamic structure design program of the rear turbine design point is programmed by C++ language.The optimized design point performance parameters of the rear turbine are input,and the design parameters of the aerodynamic structure design of rear turbine design point are determined by the selection conditions such as the rotor speed and the flow rate of the outlet air flow,etc.Finally,through the above results,a more advantageous rear turbine structure is designed to provide a more lightweight and large range of power system for the unmanned vehicles.3)Structural strength of rear turbines is analyzed.Since the structure of the rear turbine rotor is symmetrical and cyclic,the three-dimensional solid model of the blade and the part of the wheel of the turbine rotor is established by CATIA.The strength of the turbine rotor is analyzed by ANSYS software.According to the analysis of the stress and strain size and distribution of the rear turbine,it can be seen that the structural strength of the rear turbine satisfies the design requirements of the unmanned vehicle.Based on the theory of rear turbine design,the general performance and aerodynamic structure design of the rear turbine are programed by C++ language in this paper,and the design parameters of the rear turbine are obtained.At the same time,the finite element model of the blade and the part of the wheel of the rear turbine is established by using the above relevant parameters,and the structural strength is analyzed to verify the correctness of the structural design.