LDA Experimental Data of Three-Poster Jet Impingement System

Parviz Behrouzi

Volume 1, Issue 1 , October 2004, , Pages 1-8

Abstract
  During its near-ground hovering phase a Short Take-Off and Vertical Landing (STOVL) aircraft creates a complex three-dimensional flow field between jet streams, the airframe surface and the ground. A proper understanding and numerical prediction of this flow is important in the design of such aircraft. ...  Read More

Experimental Study of Vortex Shapes behind a Wing Equipped with Different Winglets

Mehdi Nazarinia; Mohammad Reza Dr. Soltani; Kaveh Ghorbanian

Volume 3, Issue 1 , March 2006, , Pages 1-20

Abstract
  An extensive experimental study is conducted to examine effects of different winglet-shapes and orientations on the vortex behind a wing, static surface pressure over the wing, and wing wake of a swept wing at various angles of attack. Four types of winglets, spiroid (forward and aft), blended, and winggrid ...  Read More

Buckling Analysis of Rectangular Laminated Composite Plates With An Edge Delamination Under Compressive Load

Mohammad Ali Kouchakzadeh

Volume 4, Issue 1 , March 2007, , Pages 1-8

Abstract
  The buckling analysis of rectangular laminated composite plates with an edge delamination under in-plane compressive loading is performed using the finite element method. Such a plate may be considered as a simplified model of stiffener plates of a stiffened panel. The buckling load and buckling mode ...  Read More

Improved Mathematical Model for Helicopters Flight Dynamics Applications

F. Saghafi; farid Shahmiri

Volume 4, Issue 3 , September 2007, , Pages 1-11

Abstract
  The purpose of this paper is concerned with the mathematical model development issues, necessary for a better prediction of dynamic responses of articulated rotor helicopters. The methodology is laid out based on mathematical model development for an articulated rotor helicopters, using the theories ...  Read More

Dynamic Stability of Step Beam Carrying Concentrated Masses under Follower Force

M. Sohrabian

Volume 4, Issue 4 , December 2007, , Pages 1-6

Abstract
  This paper investigates the dynamical behavior of an assembled beam like structure with tip masses modeling a two stage space rocket structure. The beam like structure is composed of two beams connected together carrying two masses at the free ends to model the payload, and the stabilizing fins mass ...  Read More

NUMERICAL ANALYSIS OF MAVs FLAPPING WINGS IN UNSTEADY CONDITIONS

Reza Kamali

Volume 5, Issue 1 , March 2008, , Pages 1-11

Abstract
  Today, Flapping Micro Aerial Vehicles (MAV) are used in many different applications. Reynolds Number for this kind of aerial vehicle is about 104 ~ 105 which shows dominancy of inertial effects in comparison of viscous effects in flow field except adjacent of the solid boundaries. Due to periodic flapping ...  Read More

Analysis of Radial Baffle Effects on Acoustic Characteristics of a Combustion Chamber

H. Mehrjou; Mohammad Farshchi

Volume 6, Issue 1 , March 2009, , Pages 1-12

Abstract
  An efficient finite volume approach has been used to develop a three dimensional Helmholtz acoustic solver for complex geometries. This acoustic solver was utilized to obtain characteristic mode shapes and frequencies of a baffled combustion chamber. An experimental setup, including stationary and moving ...  Read More

The Multidisciplinary Design Optimization of a Reentry Vehicle Using Parallel Genetic Algorithms

Ali Moosavi; Masoud Mirzaei; Jafar Dr. Roshanian

Volume 7, Issue 1 , March 2010, , Pages 1-8

Abstract
  The purpose of this paper is to examine the multidisciplinary design optimization (MDO) of a reentry vehicle. In this paper, optimization of a RV based on, minimization of heat flux integral and minimization of axial force coefficient integral and maximization of static margin integral along reentry ...  Read More

Verification of a CFD solver in near ground effect for aerodynamic behavior of airfoil NACA 0015

hasan sajjadi; S. F. Hosseinizadeh; Y. Vazifehshenas

Volume 8, Issue 1 , March 2011, , Pages 1-10

Abstract
  Numerical investigation was performed on NACA 0015 which is a symmetric airfoil. Pressure distribution and then lift and drag forces are verified. Changing of ground clearance was a considerable point. Also the angle of attack was changed from 0° to 10°. Pressure coefficient reaches its higher amounts ...  Read More

Fatigue Life Assessment of Composite Airplane Wing Subjected to Variable Mechanical and Thermal Loads

A. Ebadi; Ehsan Selahi

Volume 11, Issue 2 , October 2017, , Pages 1-11

Abstract
  The purpose of this paper is to estimate the fatigue life of an airplane wing with laminated composite skin, subjected to variable mechanical and thermal loads. To achieve this aim,at first, the three-dimensional model of airplane wing was drawn in CATIA software. Then, by transferring the model to the ...  Read More

Experimental and numerical investigation of unsteady flow around cylinder with four plates perpendicular to it with the rotational degree of freedom

Hassan Isvand; Ahmad Sharafi; Ali Salmaninejad

Volume 12, Issue 1 , March 2019, , Pages 1-14

Abstract
  In this study, the behavior of a subject consisting of a cylinder with 4 plates perpendicular to it with a rotational degree of freedom under airflow both through the numerical approach, known as improved discrete vortex and experimental approach were investigated. The experimental and numerical results ...  Read More

Aerospace Science and Technology
Analytical and Numerical Investigation of Effective Parameters on Energy Absorption Circular Composite Tube under Internal Pressure and Axial

Milad Noorabadi; Rahnama Malihe; Ghasemi Mohammad Amin; Jafar Eskandari Jam

Volume 12, Issue 2 , October 2019, , Pages 1-9

Abstract
  In this paper the energy absorption capacity of stiffened circular composite tube is considered. The governing equations and dynamic equilibrium are first derived and then solved. Additionally, a finite element model of reinforced circular composite tube structure is modeled. At the following, the effects ...  Read More

Designing a Fault-Tolerant Control System for the Boeing 747

Reza Soltani Nezhad; Abolqasem Naghash

Volume 13, Issue 1 , June 2020, , Pages 1-9

https://doi.org/10.22034/jast.2020.119910

Abstract
  This article examines the fault tolerance control (FTC) system for the Boeing 747. to reach this goal, firstly 6 degrees of freedom equations are simulated and linearized by using dynamic inversion method. Then, the system is controlled by a linear proportional-integral-derivative controller. To control ...  Read More

Aerospace Science and Technology
Multi-scale modeling of thermal conductivity of carbon nanotube epoxy nanocomposites- CNT

ali Vahedi; Mohammad Homayoun Sadr; Saied Shakhesi

Volume 13, Issue 2 , October 2020, , Pages 1-6

https://doi.org/10.22034/jast.2021.128047

Abstract
  Epoxy is among the most important polymers, which is extensively employed in various technologies and applications. Nevertheless, epoxy polymers present low thermal conductivities and thus the enhancement of their thermal conductivity is an important research topic. Carbon nanotubes (CNTs) owing to their ...  Read More

Aerospace Science and Technology
Aerodynamic Optimization of a Wind Turbine Blade for Maximum Annual Energy Production at Manjil Wind Farm

Mahdi Azizi; Alireza Jahangirian

Volume 14, Issue 2 , October 2021, , Pages 1-9

https://doi.org/10.22034/jast.2021.129714

Abstract
  To keep pace with current trends in the wind industry, this paper aims at the improvement of the annual energy production of a horizontal axis wind turbine by aerodynamic optimization of blades at the wind conditions of the Manjil site. To achieve this goal, the Riso wind turbine, whose characteristics ...  Read More

Aerospace Science and Technology
Investigation of fin changes effects on aerodynamic performance of airship

Sahar Noori; Mohamad Saleh Afshar; Nima Karimi

Volume 14, Issue 1 , June 2021, , Pages 1-10

https://doi.org/10.22034/jast.2021.133173

Abstract
  Airships usually have low cruising speed due to their large volume and high drag level. This makes the aerodynamic design of the vehicle, including the surfaces shape, the length-to-diameter ratio and the position of the fins, all very important. Furthermore, an important parameter in the vehicle aerodynamic ...  Read More

Aerospace Science and Technology
Mixed Mode (I/II/III) Stress Intensity Factors in Gas Turbine Blade Considering 3D Semi-elliptical Crack

Seyed mohammad navid ghoreishi; Nabi Mehri-Khansari; Houman rezaei

Volume 15, Issue 1 , June 2022, , Pages 1-13

https://doi.org/10.22034/jast.2021.294317.1077

Abstract
  Regardless of the initiation or propagation procedure of crack in a gas turbine blade, the precise expectation of the fracture behavior, such as mixed-mode Stress Intensity Factors (SIF), plays a significant role in acquiring its operational life. Therefore, multilateral three-dimensional fracture solutions ...  Read More

Aerospace Science and Technology
Surrogate Based Simulation in Multidisciplinary Design Optimization of a Space Transportation System

Hassan Naseh; Mehran MirShams; Hamid Reza Fazeley

Volume 15, Issue 2 , October 2022, , Pages 1-15

https://doi.org/10.22034/jast.2022.329569.1115

Abstract
  Recently, engineering systems are quite large and complicated. Conceptual design process of Space Transportation Systems (STSs) is a multidisciplinary task which must take into account interactions of various disciplines and analysis codes. Current approach for the conceptual design of STSs requires ...  Read More

TIME OPTIMAL SLEW MANEUVER OF MAGNETICALLY ACTUATED LEO SATELLITES

Ali Heydari; Seid H. Dr. Pourtakdoust

Volume 5, Issue 2 , June 2008, , Pages 51-56

Abstract
  Conventional magnetic attitude control methodologies require several orbital periods to accomplish the required attitude maneuvers due to the existence of an uncontrollable axis, namely the local Earth’s magnetic field vector. Since in some attitude maneuver missions the elapsed time is of critical ...  Read More