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مجله علوم و مهندسي هوافضا
معرفی نشریه
مجله علوم و مهندسي هوافضا

نشريه بين المللي علوم ومهندسي هوافضا، تحت امتياز انجمن هوافضاي ايران و داراي رتبه علمي –پژوهشي از وزارت علوم ، تحقيقات و فناوري، در راستاي اهداف علمي خود ودر جهت ارتقاء سطح علمي و دانش فني –كاربردي رشته مهندسي هوافضا در كشور وتبادل وبه روز رساني نتايج تحقيقات تجربي و علمي در اين رشته ورشته هاي مرتبط در سطح بين المللي ، پذيراي دريافت مقالات اصيل كليه دانشمندان و محققان در زمينه علوم و صنعت هوافضا مي باشد.این مجله افتخار دارد ضمن بررسی ، ارزیابی و چاپ نتایج آخرین بررسی ها و دستاوردهای کلیه دانش پژوهان هوافضا که مبتنی بر تحقیقات نظری و عملی پیشرفته بوده است ، گامی موثر در جهت اعتلای این دانش در کلیه شاخه های علمی و صنعتی مرتبط با این رشته در کشور بردارد. 

 

 


 

                     مجوز كميسيون بررسي و ارزيابي نشريات كشور مبني بر تغيير تناوب انتشار نشريه به دو فصلنامه

مقالات آخرین شماره منتشر شده از آخرین دوره نشریه
 دوره11،شماره1
 
1
Loading Estimation of Flapping Wings under Aeroelastic Effect Using Finite Element Method
( 63 بازدید ) ( 24 دانلود )  خلاصه و کلمات کلیدی
اطلاعات انتشار : دوره 11 - شماره 1
نویسندگان :
خلاصه مقاله : The aim of this paper is to provide an aeroelastic computational tool which determines the induced wing loads during flapping flight. For this purpose, a Finite Element (FE) code based on a four-node plate bending element formulation is developed to simulate the aeroelastic behavior of flapping wings in low incompressible flow. A quasi-steady aerodynamic model is incorporated into the aeroelastic model for predicting the aerodynamic loads. In order for the validation of the present tool, the modal and dynamic response analyses of a rotating flat plate under pure flapping motion are firstly examined and the effect of dynamic stiffness on the plate response, due to the presence of shortening terms in the equations of motion, is also investigated. Finally, the aeroelastic analysis of an insect-like wing under a specified motion is carried out and the induced loads including shear force and bending moment at the wing root are determined.  The obtained results signify the contribution of wing structural elasticity to the induced loads.
تخصص ها : Keywords: Aerodynamic, Aeroelastic, Flapping wing, Finite element, Dynamic stiffness

2
Active Vibration Suppression of a Nonlinear Flexible Spacecraft
( 70 بازدید ) ( 21 دانلود )  خلاصه و کلمات کلیدی
اطلاعات انتشار : دوره 11 - شماره 1
نویسندگان :
خلاصه مقاله : In this article, the issue of attitude control and active vibration suppression of a nonlinear flexible spacecraft is assessed through piezoelectric patches as actuator and sensors. Two controller loops are applied: the inner loop, to make the panel vibration damped through piezoelectric patches; and the outer loop, to perform spacecraft maneuver using the reaction wheel acting on the hub. An optimal controller is designed in the inner loop and two robust controllers are designed as the outer loop, which are used interchangeably. One is a high-ordersliding mode controller using super twisting algorithm and the other is a nonsingular terminal sliding mode controller. With respect to the non-minimum phase properties of the system, if the panel deflection is defined as the output, the output redefinition approach is introduced.The performances of the proposed controllers are compared in terms of tracking attitude trajectory, panel vibration suppression, robustness towards uncertainties, sensor noise, disturbances and nonlinearity in large maneuvers.
تخصص ها : Keywords: Active control,Flexible Spacecraft, piezoelectric patches, super twisting algorithm, nonsingular terminal sliding mode, output redefinition approach.

3
Airfoil Shape Optimization with Adaptive Mutation Genetic Algorithm
( 65 بازدید ) ( 24 دانلود )  خلاصه و کلمات کلیدی
اطلاعات انتشار : دوره 11 - شماره 1
نویسندگان :
خلاصه مقاله : An efficient method for scattering Genetic Algorithm (GA) individuals in the design space is proposed to accelerate airfoil shape optimization. The method used here is based on the variation of the mutation rate for each gene of the chromosomes by taking feedback from the current population. An adaptive method for airfoil shape parameterization is also applied and its impact on the optimum design and convergence of the optimization process isinvestigated. In order to demonstrate the efficiency of the proposed method, a geometric inverse design using Genetic Algorithm is carried out and the capability of the method for producing airfoil shapes is assessed. The performance of the method is further evaluated by an aerodynamic shape optimization. Results indicate the merits of the method in increasing the maximum objective value about7percent as well as decreasing the total computational time up to28 percent.
تخصص ها : Keywords: Genetic Algorithm; Shape Optimization; Adaptive Mutation; Computational Fluid Dynamics

4
Robust Fixed-order Gain-scheduling Autopilot Design using State-space Stability-Preserving Interpolation
( 60 بازدید ) ( 7 دانلود )  خلاصه و کلمات کلیدی
اطلاعات انتشار : دوره 11 - شماره 1
نویسندگان :
خلاصه مقاله : In this paper, a robust autopilot is proposed using stable interpolation based on Youla parameterization. The most important condition of stable interpolation between local controllers is the preservation of stability so that each local controller can ensure stability for an open neighborhood around a nominal point. The proposed design used fixed-order robust controller with parameter-dependent central polynomial for each vertex of the polytope to decrease the conservation of each local controller. A stability-preserving gain-scheduled controller was designed using a newly proposed algorithm in the flight envelop for a parameter varying model. The results of simulation confirm the efficiency of the proposed method.
تخصص ها : Keywords:Robust autopilot, stability preserving interpolation, fixed-order controller, parameter-dependent central polynomial

5
Preliminary Design of Spacecraft Attitude Control with Pulse-Width Pulse-Frequency Modulator for Rest-to-Rest Maneuvers
( 65 بازدید ) ( 14 دانلود )  خلاصه و کلمات کلیدی
اطلاعات انتشار : دوره 11 - شماره 1
نویسندگان :
خلاصه مقاله : In this paper, the preferred region of design parameters for quasi-normalized equations of single-axis attitude control of rigid spacecraft using pulse-width pulse-frequency modulator (PWPFM) is presented for rest-to-rest maneuvers. Using the quasi-normalized equations for attitude control reduces the system parameters, that is, the moment of inertia, the filter gain, and the maximum torque of modulator are merged to other parameters and the total number of parameters is reduced. Therefore, the computational burden is decreased and moreover, the results are usable for grouped parameters, regardless of the value of each parameter separately. The optimization is carried out by grid search method with the performance index of fuel consumption or number of thruster firings for a range of inputs. Finally, the suggested upper and lower bounds of parameters are obtained based on the optimization results.
تخصص ها : Keywords: Spacecraft Attitude Control, Pulse-Width Pulse-Frequency Modulator, Quasi-Normalization, Optimization

6
Local Imperfection Effects on Thermal Buckling Behavior of Composite Fiber Reinforced Truncated Conical Liner
( 66 بازدید ) ( 15 دانلود )  خلاصه و کلمات کلیدی
اطلاعات انتشار : دوره 11 - شماره 1
نویسندگان :
خلاصه مقاله : Thermal buckling behavior of truncated conical liner reinforced by laminated composite is investigated in the presence of a general initial imperfection. For this purpose, the method of virtual work and first-order strain-deformation shell theory are employed to extract equilibrium equations. To this end, a finite element code is developed using the 3D 8-node shell element with six degrees of freedom as an analysis tool. Also, the variation of thickness in conical composite shell is considered. Several problems withc-c, s-s, c-f boundary conditions are solved using code to highlight the effect of imperfection size and position. In this way, the most effective imperfection at each boundary condition is determined.
تخصص ها : Keywords: Thermal buckling, Composite shell, Finite element method, Local imperfection, Truncated conical liner

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