Study On The Technology Of Integrating Of Oxygen Supply And Antiacceleration Regulator

With the development of aviation technology,the fourth and fifth generation fighters,relying on high mobility,advanced avionics and high integration,are becoming main force in the airforce.However,it asks for stricter requirement about the pilot of protective equipment at the same time of fighter performance improvement.The importance of oxygen supply and anti-g which are key points of pilot personal protective equipment is becoming more obviously.Oxygen supply and anti-g systems on service are independent of each other.Oxygen supply system,mainly based on the lung-oxygen,has been extended so far because of its stable performance characteristics.But its low response speed and poor precision adjustment couldn’t meet the existing operational needs under the high mobility.At the same,anti-G clothing is main part of existing anti G system.The performance of its anti-charge and inflatable speed is closely related.The inflatable speed also directly affects the pilot’s abdomen comfort.It is a bottleneck to study the anti-g system while satisfying the anti-load performance and ensuring the comfort of the pilot.This paper is focused on improving the response speed of oxygen supply and the comfort of anti-G suit.Studies concerning the key technologies of the pilot’s oxygen supply and anti-G system,such as the high precision control system and the integrated design of oxygen supply and anti-G system,are carried out on the aspect of theoretical derivation,numerical simulation and experimental study.The specific research contents are as follows.(1)Scheme design and optimization of oxygen supply and anti-G system adjustment mechanism.By analyzing the advantages and disadvantages of the existing mechanical oxygen regulator,a new oxygen regulator based on digital control technology is proposed.Simultaneously,the relationship between the flow rate and the opening degree of the valve is deduced.The oxygen supply valve area under the condition of maximum oxygen supply of 250L/min and oxygen pressure of +9 G is determined.Because the mixing oxygen supply system is used under the 8000 m,the relationship of the oxygen and air flow and the valve is formulae fitting.While,the formula of pure oxygen flow supply and the valve opening is fitted above 8000 m.In addition,the mathematical model of the valve opening and the amount of support is established,and the curve of oxygen supply at different height and different opening is obtained through simulation.Based on this,the oxygen supply capacity of the designed oxygen supply system is demonstrated.Furthermore,the influence of overload on the performance of the designed oxygen supply system is studied,and the performance of the oxygen regulator is analyzed under +5G,+7G and +9G conditions.By comparing the oxygen flow condition of the oxygen regulator,the stable performance characteristics of oxygen supply are verified.Finally,the control law of the oxygen regulator is optimized to meet the need of the pilot in the case of 0.7kPa pre-charge resistance.(2)The integrated strategy of oxygen supply and anti-G regulator.Considering of the influences of the flight attitude and loads on the system of oxygen supply,the oxygen regulator and anti-G regulator are encapsulated and matched by the design of integrated strategy.Firstly,based on the impact of the aircraft under different flight conditions,the power and DSP are placed in different side of the device,so that the weight of both sides keep balance,to prevent the flight from producing unnecessary torque.In addition,a high performance genetic algorithm is developed,based on the combination of niche technology,field selection,crossover and mutation of SBX polynomials and other high performance genetic operators,to optimize design the oxygen regulator and anti-G regulator.The results show that the new algorithm can obtain the global optimal solution and then provide a reliable and general optimization method for the integrated design optimization of oxygen regulator and anti-regulator.(3)The control mode and component design.The existing mechanical structure would lead to the time delay in adjustment because of the low precision in the control and longtime response.In this paper,the control of the resistance regulator mainly takes a counterweight way to get the value of G,and then the valve is open to control the inflation of the anti-G suit by force transmission.At the same time,a detailed design of the hardware is conducted based on the digital control mode to control the above charging mode.(4)Experimental verification.The experimental investigation of the prototype is conducted in this study based on the low pressure warehouse chamber and centrifugal machine.The oxygen bottle as the oxygen supply is adopted in the testing and its inlet pressure is controlled to no more than 0.35 MPa by the pressure adjuster.The excessive pressure and the respiratory resistance are investigated in the three condition of the ventilatory capacity in 20L/min,30L/min,44L/min,respectively.The results show that the maximum respiratory resistance occurs in the ventilatory capacity of 44L/min,however,this also could meet the respiratory rate requirements of less than 1.76 kPa.Meanwhile,the performance of pressure oxygen system of anti-G suit is also conducted in the four altitude conditions of 13 km,15km,16 km,18km,respectively.It shows that the ratio of clothing pressure and overpressure can satisfy the design requirements of 3.2:1.In the mobility testing the performance of the oxygen supply and anti acceleration regulator is investigated in the condition of altitude decompression and it could meet all the 5s parameters demands.The results further validate the effectiveness of the proposed design method.