Views: 0 Author: Site Editor Publish Time: 2022-10-19 Origin: Site
In the soft refueling method, the aerodynamic instability of the refueling hose taper sleeve is affected by the airflow, which seriously affects the success rate and safety of aerial refueling/refueling.
The wake field of the tanker affects the stability of the hose taper sleeve. major factor. In this paper, the wind tunnel test method for the aerodynamic stability of the refueling hose sleeve of the aerial tanker is studied, the similarity criterion is established and analyzed, and the specific method of measuring the displacement of the hose sleeve by the binocular system is given. The automatic steering gear is used to realize the refueling. The hose is automatically retracted and released, forming a complete wind tunnel test technology for the aerodynamic stability of the refueling hose cone, and it is applied to the selection and optimization of the refueling pod, centerline platform and other components of a certain type of tanker. The results show that the test technology can effectively simulate the retraction and release process of the hose cone under the wake field of the tanker and the aerodynamic stability when the pipe length is fixed. The advantages and disadvantages of the configuration of the pod and the centerline platform can provide reliable test data for the optimization and flight test of the key fueling components of the tanker.
As a key technology of aircraft development, aerial refueling plays an irreplaceable role in improving the combat performance and combat radius of the aircraft. As the current domestic and international mainstream aerial refueling method, that is, the hose cone type aerial refueling system (referred to as soft refueling), its advantage is that it can refuel several fighters at the same time, and can achieve "partner refueling"; its disadvantage is that The hose-cone-sleeve system is very sensitive to atmospheric turbulence, and requires very high pilots when refueling and docking, and the refueling speed is slow, which increases the pilot's error rate. Although soft refueling has been gradually improved since its introduction in 1949 and its performance has been continuously improved, according to relevant literature statistics, the accident rate of aerial refueling flights is still as high as 2.5%, which is much higher than the take-off and landing stages with high accident rates. Atmospheric turbulence, tanker wake, and oil receiver nose wave will affect the safety of refueling docking, especially the complex wake field of the tanker is the most important factor affecting the aerodynamic stability of the refueling hose taper sleeve. The installation position of the taper sleeve is not ideal or under certain conditions, the taper sleeve often produces irregular position swing, which makes the docking and refueling process full of uncertainty.
In the research on the aerodynamic stability of the refueling hose taper sleeve, numerical calculation and test methods are mainly used abroad. The numerical calculation mainly includes the establishment and simulation of the wake model of the tanker and the establishment and simulation of the dynamic model of the hose taper sleeve system. In 1996, Proctor first used numerical calculation to simulate the wake vortex characteristics of the aircraft; in 1999, James W. Kamman et al. used finite element multi-body dynamics theory to discretize the cables into a rigid rod through frictionless spherical hinges. In 2007, William B. Ribbens simplified the refueling hose into a concentrated mass point connected by a spring, and the adjacent three The nodes and the hoses at both ends in the middle form a beam system, and the elastic restoring force is calculated by the simply supported beam formula. In terms of tests, flight tests are mostly used to directly verify the stability of hoses and cone sleeves during refueling, while wind tunnel tests are mostly focused on the wake field of tankers. For example, in 2002 and 2004, Edward G. Dickes and others conducted wind tunnel tests of KC-135 tanker, ICE-101 tanker, and delta-wing UAV, respectively, to directly measure the wake characteristics, and about hoses and cones There are few reports on the wind tunnel test of the aerodynamic stability of the set, and the only available information is the video image of the first phase of the aerodynamic stability test of the KC-390 tanker carried out by Embraer in the DNW wind tunnel in 2012.
The domestic research on the aerodynamic stability of the refueling hose taper sleeve was carried out relatively late, and there were few scholars who studied soft aerial refueling before 2010 [5]. In terms of numerical calculation, since 2007, Chen Bo, Hu Mengquan, Wang Wei, Zhang Shiming and others have successively carried out the research on the wake field model of the tanker and the dynamic model of the refueling hose, and simulated the effect of the wing wake on the refueling hose cone. The influence of the stability of the set [6-8]; in the flight test, the domestic main use of the H-6 tanker and the J-8 refueling docking, in 2006, the H-6 tanker and the J-10 refueling docking was realized. In the test, the pilot of the fuel receiver mainly aligns the refueling cone to complete the locking. The disturbed and irregular drift of the cone often causes the pilot to fail repeatedly [1]. The aerodynamic stability of the refueling hose and the cone is wind tunnel test. It is still blank in the country.
Because the wake field of the tanker is extremely complex, including the influence of both the wing wake vortex and the horizontal tail and vertical tail, it is impossible to simulate completely and accurately through the mathematical model, and the stability of the hose cone is extremely sensitive to the change of the flow field. Therefore, the accuracy of numerical simulation is difficult to guarantee; the direct flight test has high cost and high risk, and the test success rate often depends greatly on the pilot's experience. Therefore, as a low-cost and low-risk test method, it is very necessary to develop a wind tunnel test technology for the aerodynamic stability of the refueling hose taper sleeve with reliable test results. In 2017, the China Aerodynamic Research and Development Center, where the low speed is located, formed the wind tunnel test capability for the aerodynamic stability of the refueling hose taper for the first time in China. The influence of the refueling pod, the landing gear bulge, the position of the refueling platform, etc. on the stability of the hose and the cone sleeve, the test results provide the basis for the optimization of the tanker model selection, the location of the refueling system, etc., and improve the reliability of the aerial refueling flight test. Security is important.
