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Optimization of High-Speed WIG Airfoil with Consideration of Non-ground Effect by a Two-Step Deep Learning Inverse Design Method

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Transactions of Nanjing University of Aeronautics and Astronautics 2025年第1期42卷 56-69页

作者： WANG Chenlu SUN Jianhong ZHENG Daren SUN Zhi ZUO Si LIU Hao LI Pei Key Laboratory of Aircraft Environment Control and Life Support Ministry of Industry and Information TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China Key Laboratory of Civil Aviation Emergency Science&Technology Civil Aviation Administration of ChinaNanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China

Under complex flight conditions,such as obstacle avoidance and extreme sea state,wing-in-ground(WIG)effect aircraft need to ascend to higher altitudes,resulting in the disappearance of the ground effect.A design of high-speed WIG airfoil considering non-ground effect is carried out by a novel two-step inverse airfoil design method that combines conditional generative adversarial network(CGAN)and artificial neural network(ANN).The CGAN model is employed to generate a variety of airfoil designs that satisfy the desired lift-drag ratios in both ground effect and non-ground effect ***,the ANN model is utilized to forecast aerodynamic parameters of the generated *** results indicate that the CGAN model contributes to a high accuracy rate for airfoil design and enables the creation of novel airfoil ***,it demonstrates high accuracy in predicting aerodynamic parameters of these airfoils due to the ANN *** method eliminates the necessity for numerical simulations and experimental testing through the design procedure,showcasing notable *** analysis of airfoils generated by the CGAN model shows that airfoils exhibiting high lift-drag ratios under both flight conditions typically have cambers of among[0.08c,0.105c],with the positions of maximum camber occurring among[0.35c,0.5c]of the chord length,and the leading-edge radiuses of these airfoils primarily cluster among[0.008c,0.025c]

关键词： conditional generative adversarial network(CGAN) artificial neural network(ANN) airfoil design wing-in-ground(WIG)aircraft ground effect

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Flow Characteristics of Double-Cruciform Parachute at Inflating and Inflated Conditions

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第6期35卷 992-999页

作者： Fang Ming Sun Jianhong Zhang Tong Hou Bin Zhang Yantai Key Laboratory of Aircraft Environment Control and Life Support of MIIT College of Aerospace EngineeringNanjing University of Aeronautics and Astronautics

The fluid-structure interaction (FSI) between the canopy and flow field on the inflating and inflated conditions is investigated based on the arbitrary Lagrange-Euler (ALE) method,in both a single-and double-cruciform parachute *** projection area of canopy is calculated in the inflation *** flow field characteristics and the interaction between canopies are *** showed that,with free stream velocity of 50m/s,overinflation phenomenon would not occur during the inflation process of the double-cruciform-parachute system,because the collision and extrusion of the two canopies during inflation obstructed the oscillation of the inner ***,compared with the single-cruciform parachute,the vortex motion in the wake of double-cruciform-parachute is more *** the double-cruciform parachute system oscillated at a velocity of 50 m/s with an angle of less than 6.8°.By comparison,the oscillation angle of the single-cruciform parachute was within 3.5° at the velocity of 50m/*** results are consistent with those of the wind tunnel test.

关键词： process of inflation arbitrary Lagrange-Euler(ALE) Lamb vector divergence cruciform parachute

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Effect of fuel type on the performance of an aircraft fuel tank oxygen-consuming inerting system

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Chinese Journal of Aeronautics 2021年第3期34卷 82-93页

作者： Xiaotian PENG Shiyu FENG Chaoyue LI Chen CHEN Weihua LIU Key Laboratory of Aircraft Environment Control and Life Support of MIIT College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

The properties of aviation fuel have a great influence on the performance of oxygenconsuming inerting systems. Based on the establishment of the catalytic inerting process, the flow relationship of each gas component flowing through the catalytic reactor was derived. The mathematical model of the gas concentration in the gas phase of the fuel tank was established based on the mass conservation equation, and the fuel tank model was verified by performing *** results showed that the fuel type exerts a considerably higher influence on the performance of the oxygen-consuming inerting system compared to the corresponding influence on the hollow fiber membrane system, and the relative magnitude of the inerting rates of the four fuel types is RP5 > RP3 > RP6 > JP8. In addition, a higher catalytic efficiency or fuel load rate corresponds to a higher rate of decrease of the oxygen concentration in the gas phase, and the inerting time is inversely proportional to the suction flow rate of the fan. When different fuels are used, the amount of cooling gas and water released from the inerting system are different. Therefore, the influence of fuel type on the system performance should be extensively considered in the future.

关键词： Aviation fuel Catalytic reactions Hollow fiber membrane Inert gas Mathematical model

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Measurement of mass diffusion coefficients of O_2 in aviation fuel through digital holographic interferometry

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Chinese Journal of Aeronautics 2019年第5期32卷 1184-1189页

作者： Chaoyue LI Weihua LIU Xiaotian PENG Lei SHAO Shiyu FENG Key Laboratory of Aircraft Environment Control and Life Support of Ministry of Industry and Information Technology College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics

The experimental apparatus to measure the mass diffusion coefficients of O2 in aviation fuel was constructed based on the digital holographic interferometry method. The theory of mass diffusion coefficient and interference image processing were introduced in detail. The accuracy of the experiment was verified by measuring the mass diffusion coefficient of 0.33 mol/L KCl in aqueous solution at 298.15 K. The mass diffusion coefficients of O_2 in RP3 and RP5 aviation fuels were measured at temperature from 278.15 K to 333.15 K, and the Arrhenius equation was employed to fit the experimental data. In terms of the Stokes-Einstein equation, the viscosities of these two aviation fuels were tested to estimate the correlation among mass diffusion coefficient, viscosity and temperature. A uniform polynomial calculation correlation was proposed to predict the mass diffusion coefficients of O_2 in both RP3 and RP5 aviation fuels, and its accuracy is considerably higher than that of the Stokes-Einstein equation.

关键词： Aviation fuel Diffusion coefficients Digital holographic interferometry Oxygen Viscosity

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Shock-Wave/Rail-Fasteners Interaction for Two Rocket Sleds in the Supersonic Flow Regime

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Fluid Dynamics & Materials Processing 2020年第4期16卷 675-684页

作者： Bin Wang Jing Zheng Yuanyuan Yu Runmin Lv Changyue Xu Key Laboratory of Aircraft Environment Control and Life Support MIITNanjing University of Aeronautics and AstronauticsNanjing210016China AVIC Aerospace Life-Support Industries Ltd.Xiangyang441003China

Rocket sleds belong to a category of large-scale test platforms running on the *** applications can be found in many fields,such as aerospace engineering,conventional weapons,and civil high-tech *** the present work,shock-wave/rail-fasteners interaction is investigated numerically when the rocket sled is in supersonic flow *** typical rocket sled models are considered,i.e.,an anti-D shaped version of the rocket sled and an axisymmetric slender-body *** dynamics for Mach number 2 have been simulated in the framework of a dynamic mesh *** emerging shock waves can be categorized as head-shock,tailing-shock and *** unsteady large-scale vortex and related shock dynamics have been found for the anti-D shaped rocket ***,a quasi-steady flow state exists for the slender-body shaped rocket *** indicates that the axisymmetric geometry is more suitable for the effective production of rocket *** the help of power spectral density analysis,we have also determined the characteristic frequencies related to shock-wave/rail-fasteners ***,a harmonic phenomenon has been revealed,which is intimately related to a shock wave reflection mechanism.

关键词： Rocket sled shock wave dynamic mesh method ground effect

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Fluid structure interaction of supersonic parachute with material failure

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Chinese Journal of Aeronautics 2023年第10期36卷 90-100页

作者： Shunchen NIE Li YU Yanjun LI Zhihong SUN Bowen QIU College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Aircraft Environment Control and Life Support MIITNanjing University of Aeronautics and AstronauticsNanjing 210016China

The material damage of parachute may occur in parachutes at high speeds,and the growth of tearing may finally lead to failure of aerospace *** order to study the damage mechanism of parachute,a material failure model is proposed to simulate the failure of canopy *** inflation process of supersonic parachute is studied numerically based on Arbitrary Lagrange Euler(ALE)*** ALE method with material failure can predict the transient parachute shape with damage propagation as well as the flow characteristics in the parachute inflation process,and the simulated dynamic opening load is consistent with the flight *** damage propagation mechanism of parachute is then investigated,and the effect of parachute velocity on the damage process is *** results show that the canopy tears apart by the fast flow from the initial damaged area and the damaged canopy shape leads to the asymmetric change of the flow *** the increase of Mach number,the canopy tearing speed increases,and the tearing directions become uncertain at high Mach *** dynamic load when damage occurs increases with the Mach number,and is proportional to the dynamic pressure above the critical Mach number.

关键词： Arbitrary Lagrange Euler method Dynamic loads Fluid structure interaction Material failure model Parachute damage

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Experimental comparison between aircraft fuel tank inerting processes using NEA and MIG

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Chinese Journal of Aeronautics 2018年第7期31卷 1515-1524页

作者： Lei SHAO Weihua LIU Chaoyue LI Shiyu FENG Chenchen WANG Jun PAN Key Laboratory of Aircraft Environment Control and Life Support of MIIT Nanjing University of Aeronautics and Astronautics Nanjing 210016 China College of Aeronautics Chongqing Jiaotong University Chongqing 400074 China Jiangsu Province Key Laboratory of Aerospace Power System Nanjing Engineering Institute of Aircraft Systems Nanjing 210016 China

Fuel tank inerting technologies are able to reduce the fire risk by injection of inert gas into the ullage or fuel, the former called ullage washing and the latter fuel scrubbing. The Green On-Board Inert Gas Generation System（GOBIGGS） is a novel technology based on flameless catalytic combustion, and owning to its simple structure and high inerting efficiency, it has received a lot of attentions. The inert gas in the GOBIGGS is mainly comprised of CO2, N2, and O2（hereinafter, Mixed Inert Gas（MIG））, while that in the On-Board Inert Gas Generation System（OBIGGS）, which is one of the most widely used fuel tank inerting technologies, is NitrogenEnriched Air（NEA）. The solubility of CO2 is nearly 20 times higher than that of N2 in jet fuels,so the inerting capability and performance are definitely disparate if the inert gas is selected as NEA or MIG. An inerting test bench was constructed to compare the inerting capabilities between NEA and MIG. Experimental results reveal that, if ullage washing is adopted, the variations of oxygen concentrations on the ullage and in the fuel are nearly identical no matter the inert gas is NEA or MIG. However, the ullage and dissolved oxygen concentrations of MIG scrubbing are always higher than those of NEA scrubbing.

关键词： Dissolved oxygen Experiment Fuel tanks Inert gases Mixed Inert Gas(MIG) Nitrogen-Enriched Air(NEA) Oxygen

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Performances of airborne vapor cycle system under a typical helicopter flight profile

Performances of airborne vapor cycle system under a typical ...

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CSAA/IET International Conference on aircraft Utility Systems 2020, AUS 2020

作者： Zhu, Zihang Fu, Chunda Xu, Yu Xia, Wenqing Key Laboratory of Aircraft Environment Control and Life Support MIIT Nanjing University of Aeronautics and Astronautics Nanjing China

ISBN: (纸本)9781839535635

Based on AMESim, a simulation model of airborne vapor cycle system was established, and solved under a typical helicopter flight profile, by controlling the compressor rotation speed via the proportional-integral method. The results show that the lower the cabin setting temperature is, the greater the refrigerating capacity of the system is, the smaller the COP is, the greater the heat transfer efficiency of the microchannel heat exchangers is, and the greater the refrigerant pressure drop is. Besides, the characteristics of system and its heat exchangers change dramatically at different flight phases. In the ground standby and climbing phases, the characteristics change obviously;in the cruising phase II, they remain stable as the cabin setting temperature is achieved;in the descending phase, they increase and then decrease due to the coupling effect of flight velocity and ambient temperature, except for the COP which keeps declining;in the ground parking phase, they tend to be stable. © 2020 Institution of Engineering and Technology. All rights reserved.

关键词： Heat exchangers

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Numerical simulation of effects of active flow control on an aero-engine inlet 3

Numerical simulation of effects of active flow control on an...

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3rd International Academic Exchange Conference on Science and Technology Innovation, IAECST 2021

作者： Zhan, Haoran Key Laboratory of Aircraft Environment Control and Life Support MIIT Nanjing University of Aeronautics and Astronautics Nanjing China

ISBN: (纸本)9781665402675

In order to solve problems of serious flow separation and large flow field distortion in the aero-engine inlet, we have carried out a numerical study on the effects of blowing control on an aero-engine inlet. The blowing control mechanism and influence of parameters such as blowing pressure ratio, blowing angle β and blowing location were analyzed in details. The results show that blowing control can effectively improve the inlet performance, and its control mechanism is to supplement energy to the boundary layer, overcome the adverse pressure gradient and delay the flow separation. When blowing angle β=10°, the effect of blowing control increases first and then decreases with the increase of blowing pressure ratio. When the blowing pressure ratio is 3.5, the blowing effect is first enhanced and then weakened with the increase of the blowing angle β. The smaller blowing angle β can ensure that the blowing flow is always located in the boundary layer and avoid mixing with the mainstream. By analyzing the control effects of three blowing positions, the change of inlet performance with blowing parameters is obtained, and the results show that different blowing positions have different effects on the control effect. © 2021 IEEE.

关键词： Flow separation

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A hybrid piecewise FDD strategy for refrigeration charge fault of airborne vapor-compression cycle system

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INTERNATIONAL JOURNAL OF REFRIGERATION 2022年 135卷 164-173页

作者： Sun, Chengbin Wang, Hexu Jiang, Yanlong Gao, Zanjun Wang, Ju [a]Key Laboratory of Aircraft Environment Control and Life Support MIIT Nanjing University of Aeronautics and Astronautics 29 Yudao St. Nanjing 210016 China [b]Aviation Key Laboratory of Science and Technology on Aero Electromechanical System Integration Nanjing 211106 China

Many researchers have carried out study on refrigerant charge fault for variable refrigerant flow (VRF) airconditioning system, while few pay attention to refrigerant charge fault for vapor-compression refrigerant cycle system (VCS) of enhanced vapor injection (EVI) with a flash tank onboard. To develop a strategy for refrigerant charge fault of the above system, the optimization methods have been implemented to predict the refrigerant charge level (RCL) based on virtual refrigerant charge (VRC) models. Firstly, Pearson correlation coefficient analysis is employed to obtain the characteristic parameters. Secondly, a piecewise modified VRC model with the different characteristic parameters from VRC models is obtained for two cases of RCL < 75% and RCL > 75%. Meanwhile, combined with the principal component analysis (PCA) and the support vector machine (SVM) algorithm, a PCA-SVM model is developed to improve the prediction accuracy, and the average root mean squared error (RMSE) is only 7.8 compared to 14.9 of the modified VRC model when RCL > 75%, meanwhile, the correctly detected ratio is improved from 62.8% to 84.5%. Then, for solving the difficulty of fault detection and diagnosis (FDD) when RCL > 160%, the moving time window average (MA) algorithm is introduced and an online PCA-MA-SVM model is developed. Finally, a hybrid piecewise FDD strategy combined with three models for refrigeration charge fault in airborne VCS of EVI with a flash tank is obtained.

关键词： Vapor-compression refrigeration cycle system Enhanced vapor injection Refrigerant charge fault support vector machine Moving time window average

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