The energy absorption characteristics of tapered honeycomb sandwich cylindrical columns under axial crushing loads
Nader
Vahdat Azad
author
Saeed
Ebrahimi
author
text
article
2015
per
The energy absorption characteristics of honeycomb sandwich cylindrical columns under axial crushing process depend greatly on the amount of material which participates in the plastic deformation. The interaction effects between the honeycomb core and the column skins greatly improve the energy absorption efficiency, which in turns depend on the shape of honeycomb core. Therefore, in this paper, the energy absorption characteristics of tapered honeycomb sandwich cylindrical columns with square, triangle, kagome and diamond cores under axial crushing loads are investigated by nonlinear finite element analysis. In this paper energy absorption, crushing force and interaction effect between skin and core for 4 models are investigated. Also energy absorption efficiency for tapered tube and cylindrical tube with similar core is investigated and the results are compared. In order to reduce the computational cost of crush simulations, finite element method is employed to formulate specific energy absorption and peak crushing force.
Journal of Aeronautical Engineering
Shahid Sattari Aeronautical University of Science and Technology-Iranian Aerospace Society
Director-in-Charge:
Dr. Akbar Cheraqi
Editor-in-Chief:
Dr. Farhad Javidrad
Associate Editor:
Dr. Vahid Khalafi
Website Manager:
Amir Ehsan Zamanian
Eng. Nima Mansour Lakouraj
English Text Editor:
Dr. Roohollah Maleki
17359449
17
v.
2
no.
2015
1
9
https://www.joae.ir/article_121572_169a852437ffee7e6d3a64d2669ea984.pdf
Identifying the Challenges of Innovation and Providing Solutions in Aircraft Industry by the Comparative Study of South Korea
Jalal
Raei
author
Hamid
Ghasemi Poursabet
author
Mahdi
Hadian
author
text
article
2015
per
This study aimed to identify the challenges of innovation in Iran aircraft industry and provide solutions to overcome these challenges. In this regard, through reviewing various related literature, these challenges were first identified and then, by interviewing with experts in the field, the challenges of innovation in the industry were evaluated from their perspective. Finally, the mentioned interviews are analyzed and their results are presented. Also, in one part of the study, a comparative study of South Korea was done on the challenges of innovation in this industry there and ways adopted to overcome these challenges. The results of the study showed that lack of skilled human resource, lack of relationship between industry and university and knowledge-based companies, excessive government intervention, lack of long-term research strategies and short-term perspective of managers are the most important challenges of innovations in aircraft industry.
Journal of Aeronautical Engineering
Shahid Sattari Aeronautical University of Science and Technology-Iranian Aerospace Society
Director-in-Charge:
Dr. Akbar Cheraqi
Editor-in-Chief:
Dr. Farhad Javidrad
Associate Editor:
Dr. Vahid Khalafi
Website Manager:
Amir Ehsan Zamanian
Eng. Nima Mansour Lakouraj
English Text Editor:
Dr. Roohollah Maleki
17359449
17
v.
2
no.
2015
10
22
https://www.joae.ir/article_121574_7881720c7d43cbacf9954c5b314b20bd.pdf
تحلیل عددی نفوذ بمبهای سنگرشکن با انرژی جنبشی غیرهستهای (GBU) در سازههای زیرزمینی
Hassan
Salehi
author
Mahdi
Heshmatirad
author
Mahmoud
Vaseli Khabbaz
author
text
article
2015
per
To build the safe underground shelters which are covered by the layers of soil and concrete is one of the common ways to protect military activities. The bunker buster bombs are the main threat for underground shelters. The main aim of this research is to evaluate the piercing action of these bombs in soil and concrete and to provide a base line for further research on this area. In this study ABAQUS software is used to numerically simulate the penetration process. In the current paper, a method to minimize the penetrability of BLU-113 warhead in only soil and concrete and then in a given underground construction is evaluated. The results of analytical and numerical analyses represented that putting the interlaced of concrete and soil layers minimize probing of BLU-113 can be observed.
Journal of Aeronautical Engineering
Shahid Sattari Aeronautical University of Science and Technology-Iranian Aerospace Society
Director-in-Charge:
Dr. Akbar Cheraqi
Editor-in-Chief:
Dr. Farhad Javidrad
Associate Editor:
Dr. Vahid Khalafi
Website Manager:
Amir Ehsan Zamanian
Eng. Nima Mansour Lakouraj
English Text Editor:
Dr. Roohollah Maleki
17359449
17
v.
2
no.
2015
23
43
https://www.joae.ir/article_121580_1523aba456d122d3e31945bae0280c49.pdf
Offering the model based on system dynamics for improvement of flight safety
Atefeh
Ebrahimi
author
Amir
Najafi
author
text
article
2015
per
Since the flight safety management is one of the main issues in the aviation industry, and it has a critical role in preventing different accidents. Considering the non-stop technological and dynamic improvements in today’s world, a change in the attitude of this industry’s managers to dynamic and systematic view, can lead to a better performance and efficiency in scheduling and planning in the mentioned industry. In first step of this research, the most important affected factors which have a considerable influence on flight safety was distinguished from library sources and expert’s opinions. In the second step, the chosen factors were categorized based on the kind of relations between them, then the type of their relations and the impression rate of each factor were classified based on expert’s opinions. After that the variables and relations were analyzed with Vensim software, and the model were made.
Journal of Aeronautical Engineering
Shahid Sattari Aeronautical University of Science and Technology-Iranian Aerospace Society
Director-in-Charge:
Dr. Akbar Cheraqi
Editor-in-Chief:
Dr. Farhad Javidrad
Associate Editor:
Dr. Vahid Khalafi
Website Manager:
Amir Ehsan Zamanian
Eng. Nima Mansour Lakouraj
English Text Editor:
Dr. Roohollah Maleki
17359449
17
v.
2
no.
2015
44
56
https://www.joae.ir/article_121582_9a915fde67b1b000f41624bba74b17eb.pdf
Multi-Objective Emergency Landing Trajectory Design Based on Motion Primitives
Davood
Asadi
author
Mahdi
Sabzehparvar
author
Ali
Negahban Boron
author
text
article
2015
per
This paper presents an efficient approach to determine cost criteria weights in multi-objective optimization (MOO) problem of a left wing damaged airplane trajectory generation in proximity to local terrain. Different cost criteria including terrain avoidance, Safety Value Index (SVI), and safe landing requirements such as touchdown heading and position, airspeed, and glide slope are defined. A potential field strategy is utilized to rapidly generate emergency landing trajectories based on a library of the damaged airplane motion primitives including trim states and transition maneuvers between the trim conditions. For multiple-objective problems, the objectives are generally conflicting, preventing simultaneous optimization of each objective. Considering multiple objectives in trajectory planning in this paper, the optimum weights of each cost function is derived using Pareto analysis and pairwise comparison of normalized costs and the total cost is defined based on weighted sum method. Simulation results demonstrate the effectiveness of weight selection based on the proposed method to autonomously plan safe landing trajectories.
Journal of Aeronautical Engineering
Shahid Sattari Aeronautical University of Science and Technology-Iranian Aerospace Society
Director-in-Charge:
Dr. Akbar Cheraqi
Editor-in-Chief:
Dr. Farhad Javidrad
Associate Editor:
Dr. Vahid Khalafi
Website Manager:
Amir Ehsan Zamanian
Eng. Nima Mansour Lakouraj
English Text Editor:
Dr. Roohollah Maleki
17359449
17
v.
2
no.
2015
57
72
https://www.joae.ir/article_121585_f125eb2b9f5e86130ead4e216cfb0e44.pdf
The effect of rake angle and cutting speed on residual stress in broaching process of Ti6Al4V for air engines
Mohammad
Kazemi Nasrabadi
author
text
article
2015
per
There is wide range usage of titanium alloys in aeronautical and aerospace industries due to corrosion resistant and excellent strength to weight ratio. Machining process may be affects material properties and residual stresses in surface or near surface layers of the work piece. In addition, residual stresses have important rule in machining work piece operation. This stresses are functions of machining parameters such as cutting speed, feed rate, rake angle, tool geometry and lubrication condition. In the current research broaching process of Ti6Al4V is simulated in abacus software. After modeling, the effect of rake angle on residual stresses is analyses for 5, 10, 15 and 20 degree rake angels for 15, 30 and 45 m/min cutting speeds. Also the effect of different cutting speeds such as 15, 30 and 45 m/min for constant cutting depth of cut of 0.05 mm and 5 degree rake angle was investigated.
Journal of Aeronautical Engineering
Shahid Sattari Aeronautical University of Science and Technology-Iranian Aerospace Society
Director-in-Charge:
Dr. Akbar Cheraqi
Editor-in-Chief:
Dr. Farhad Javidrad
Associate Editor:
Dr. Vahid Khalafi
Website Manager:
Amir Ehsan Zamanian
Eng. Nima Mansour Lakouraj
English Text Editor:
Dr. Roohollah Maleki
17359449
17
v.
2
no.
2015
73
81
https://www.joae.ir/article_121586_ca347a65d4e3bc59fbc525f8ae4a865a.pdf
Improving Safety in the TABRIZ Airport via Precision Approach Based on Continues Descent
Javad
Parastari
author
Kiomars
Ilami
author
text
article
2015
per
In this manuscript, two new precision approach plans, and a new flight path to join the Initial Approach Fix (IAF) for the TABRIZ airport were designed which enable flights to earn economical and operational benefits. The most important outcome of this research focuses on improving safety matters with introducing continues descent approach in the TABRIZ airport regarding Performance Based Navigation (PBN) requirements.
Journal of Aeronautical Engineering
Shahid Sattari Aeronautical University of Science and Technology-Iranian Aerospace Society
Director-in-Charge:
Dr. Akbar Cheraqi
Editor-in-Chief:
Dr. Farhad Javidrad
Associate Editor:
Dr. Vahid Khalafi
Website Manager:
Amir Ehsan Zamanian
Eng. Nima Mansour Lakouraj
English Text Editor:
Dr. Roohollah Maleki
17359449
17
v.
2
no.
2015
82
89
https://www.joae.ir/article_121589_8f9c0ca55af2bc9cb2e0c16c4c075ad2.pdf