Research On The Hydraulic Test System Of The Civil Aircraft

The civil aviation transportation industry of our country is growing explosively, however, we don’t have our own civil aircraft.As it’s extremely important to develop our own civil aircraft, the government are now putting an huge effort into developing it.The hydraulic system of civil aircraft is crucial to the whole civil aircraft and the result of its development have a great influence on the ultimate success of the development of our own aircraft.However,the lacking of research base on civil aircraft’s hydraulic system and specialized test rig of hydraulic system of civil aircraft has greatly restricted the development progress of civil aircraft.Therefore,it’s really necessary to built a specialized testrig of civil aircraft to prove that the design works in the required way,the Hydraulic Assessment System of Civil Aircraft(HASCL) is developed under this background.The working pressure of HASCL is28MPa,and there are4power channels which include three hydraulic circuits and one distributed electro-hydraulic actuator(EBHA).In order to further enhance the reliability of the whole system, a two-way Power Transfer Unit(PTU) is used. According to the symmetry of the flow rate of hydraulic system loads,they can be divided into symmetric load and asymmetric load and can be simulated in different way.The HASCL can be used to verify the hydraulic system schematic of civil aircraft with different working pressure(below28MPa)and different layouts.providing an effective platform for the development of our own civil aircraft.This thesis include the following6chapters:Chapter one, the hydraulic system of civil aircraft is simply introduced at first,then the re-search progress at home and abroad are compared.The result shows that we are far behind foreign countries in this field and indicates the urgency of carrying out relevant research. At last,the research contents and key technologies in this thesis are pointed out.Chapter two, first, the reason that the working pressure selection is elaborated, then, hydraulic loads are analyzed and the simulation plans of hydraulic loads and pump assembly and reservoir assembly are developed.At last, the whole hydraulic system schematic is given out.Chapter three, at first, the four typical working conditions of civil aircraft’s hydraulic system are analyzed, and the hydraulic control logic of the main hydraulic components are developed. After that, the control and test system of the test rig according to the statistic result of the signals in the system are developed.At last, the integrated management software which combined the control logic and control and test system are finally developed.Chapter four, the performance of the loads in hydraulic system are deeply analyzed and the loads in AMEsim after building the AMEsim model are simulated. The performance of extra-force which inherently existing in the simulation plan of the asymmetrical load in hydraulic system No.2is especially elaborated,and putting forward the control method to compensate the extraforce.At last,the validity of the extra-force compensating strategy by co-simulation with Simulink and AMEsim are proved.chapter five, Many different research on the test rig to verify the hydraulic schematic are carried out, the load simulation plan are tested, the extra-force compensating strategy’s actual effect with simulation are compared.Then, the reliability of the whole system are analyzed.chapter six, The whole thesis and point out the direction of further reseach are concluded.