Conceptual design and sizing of airframe panels according to safe-life acoustic fatigue criteria

2011 ◽  
Vol 115 (1163) ◽  
pp. 15-27 ◽  
Author(s):  
R. M. Ajaj ◽  
G. Allegri ◽  
A. T. Isikveren
Keyword(s):  
Conceptual Design ◽  
Design Stage ◽  
Skin Thickness ◽  
Analysis Tool ◽  
Reinforced Plastics ◽  
Safe Life ◽  
Sonic Fatigue ◽  
The Impact ◽  
Acoustic Fatigue ◽  
Fatigue Endurance

Abstract This paper presents a methodology that permits accounting for acoustic fatigue effects when sizing safe-life structural skin-stringer panels at the conceptual design stage of aircraft product development. The approach is based upon estimation of the maximum noise radiated from an entry-into-service year 2020 turbofan. Sonic fatigue endurance is assessed for different skin-stringer panels having different values of skin thickness, rib pitch and stringer pitch. Three different materials were considered in this study: aluminium 2024-T3 alloys (Al 2024-T3); carbon fibre-reinforced plastics (CFRP); and, glass reinforced fibre metal laminate (Hybrid Glare-3). The study resulted in CFRP having the most favourable sonic fatigue performance. In order to link economic considerations into technical decision making, the sonic endurance methods were coupled with an industry grade costing analysis tool (SEER-HTM) to examine the impact of safe-life design on the panel cost and weight. The presented methodology has been shown to be sufficiently generic in nature and robust. This will not only assist in identifying acoustic fatigue as a potential critical design scenario, but will also increase throughput during conceptual design sizing and optimisation.

scholarly journals Conceptual design of an aircraft for Mars mission

2019 ◽  
Vol 91 (6) ◽  
pp. 886-892
Author(s):  
Agnieszka Kwiek
Keyword(s):  
Stability Analysis ◽  
Dynamic Stability ◽  
Conceptual Design ◽  
Design Stage ◽  
Content Type ◽  
Mars Mission ◽  
Longitudinal Dynamic ◽  
Short Period ◽  
The Impact ◽  
Tailless Aircraft

Purpose The purpose of this paper is to present the results of a conceptual design of Martian aircraft. This study focuses on the aerodynamic and longitudinal dynamic stability analysis. The main research questions are as follows: Does a tailless aircraft configuration can be used for Martian aircraft? How to the short period characteristic can be improved by side plates modification? Design/methodology/approach Because of a conceptual design stage of this Martian aircraft, aerodynamic characterises were computed by the Panukl package by using the potential flow model. The longitudinal dynamic stability was computed by MATLAB code, and the derivatives computed by the SDSA software were used as the input data. Different aircraft configurations have been studied, including different wing’s aerofoils and configurations of the side plate. Findings This paper presents results of aerodynamic characteristics computations and longitudinal dynamic stability analysis. This paper shows that tailless aircraft configuration has potential to be used as Martian aircraft. Moreover, the study of the impact of side plates’ configurations on the longitudinal dynamic stability is presented. This investigation reveals that the most effective method to improve the short period damping ratio is to change the height of the bottom plate. Practical implications The presented result might be useful in case of further design of the aircrafts for the Mars mission and designing the aircrafts in a tailless configuration. Social implications It is considered by the human expedition that Mars is the most probable planet to explore. This paper presents the conceptual study of aircraft which can be used to take the high-resolution pictures of the surface of Mars, which can be crucial to find the right place to establish a potential Martian base. Originality/value Most of aircrafts proposed for the Mars mission are designed in a configuration with a classic tail; this paper shows a preliminary calculation of the tailless Martian aircraft. Moreover, this paper shows the results of a dynamic stability analysis, where similar papers about aircrafts for the Mars mission do not show such outcomes, especially in the case of the tailless configuration. Moreover, this paper presents the results of the dynamic stability analysis of tailless aircraft with different configurations of the side plates.

Evaluation Method for Conceptual Design Scheme Based on Fuzzy Mathematics

2012 ◽  
Vol 591-593 ◽  
pp. 25-29
Author(s):  
Peng Fei Tian ◽  
Shi Yan ◽  
Bi Ru Li
Keyword(s):  
Decision Making ◽  
Conceptual Design ◽  
New Product Development ◽  
Evaluation Method ◽  
Design Stage ◽  
Fuzzy Mathematics ◽  
Qualitative Information ◽  
Design Scheme ◽  
The Impact ◽  
Mathematics Method

Selecting the favorable conceptual design scheme is the first step to make a new product development (NPD) successfully. To guarantee reliability and rationality of decision-making about multiple design schemes in conceptual design stage under the impact of uncertainties and qualitative information, we have employed KJ method to cluster the evaluation factors into 5 clusters such as emotion, ergonomics, aesthetics, core technology, and impact; and fuzzy mathematics method to deal with uncertainties and qualitative information effectively. The weights of evaluation factors were calculated by analytical hierarchy process (AHP). Fuzzy mathematics method is the comprehensive evaluation method and quantitative analysis which based on the “maximum membership degree evaluation”. All design schemes are ranked and selected according to the multiple evaluation score of parts with their weights. Finally, a case study for decision-making is presented to demonstrate the application of the evaluation method.

scholarly journals An Analysis Tool for the Conceptual Design of High-Lift Systems

2021 ◽  
Author(s):  
William J.M. Bissonnette
Keyword(s):  
Conceptual Design ◽  
Analysis Tool ◽  
High Lift ◽  
Induced Drag ◽  
Multiple Data ◽  
Robust Model ◽  
Conceptual Design Phase ◽  
Wake Interactions ◽  
Wake Model ◽  
The Impact

An aerodynamic analysis tool for the conceptual design of high-lift devices has been developed. The method employs a higher-order potential ow method that uses elements of distributed vorticity. The subsequent numerically robust model allows for strong wake interactions, even when using a relaxed wake. The method predicts lift and induced drag values that compare well with multiple data experiments, and, when implemented in a panel code, maximum lift predictions of a high-lift system are found with an error of 6% from experimental data. This method is used to assess the impact that various wake models have on lift and induced drag predictions. This study shows that significant errors can be introduced when employing a prescribed wake model set to extreme angles. Compared to an approach using CFD, the computational expense of these models is relatively low. A single analysis requires minutes, making these models suitable for the iterative conceptual design phase

Systems Engineering Approach for Pre-Conceptual Design of DEMO Divertor

2018 ◽  
Author(s):  
Domenico Marzullo ◽  
Danilo N. Dongiovanni ◽  
Jeong Ha You
Keyword(s):  
Power Plant ◽  
Change Management ◽  
Conceptual Design ◽  
Systems Engineering ◽  
Life Cycles ◽  
Design Stage ◽  
Fusion Power ◽  
Fusion Power Plant ◽  
Engineering Approach ◽  
The Impact

The DEMOnstration Fusion power Plant (DEMO) will be a key step towards Fusion Power Plant technology. It represents the single step to a commercial fusion power plant, in charge of demonstrating the viability of relevant technologies. Indeed, the development of tokamak sub-systems has to take into account interface, structural and functional requirements and multi-physics issues that can be completely known only during the development of the design process. This leads to difficulties to be faced during the conceptual design, mainly related to the identification of the main requirements, the change management and the sub-system integration. The Systems Engineering approach aims to support the design and management of complex systems over their life-cycles, providing a systematic approach for the definition of customer needs and required functionality from the early stage of the design, as well as for the design synthesis and the system validation and verification. Among the tokamak sub-systems, the divertor is the one devoted to power exhaust management and represents, at the same time, one of the most challenging components, in terms of materials, technologies and manufacturing. Current design activities, conducted in the in the framework of EUROfusion Consortium are in a pre-conceptual phase. Despite the early design stage, a systems engineering approach is being applied as an integrated, interdisciplinary R&D effort. The paper therefore presents the modeling effort to the conceptual design of DEMO divertor aimed at identifying both system main functions and expected behavior, given the constraints imposed from either project requirement or from current viability of technological solutions. To allow for flexibility in design needed to explore the feasibility of different solutions at this pre-conceptual stage, the impact of possible changes in high level requirement or interfaces is also investigated. This is also achieved through the allocation of the requirements to the affected components and providing efficient traceability. Therefore, the proposed modelling approach is intended to support the whole divertor conceptual design stage, allowing for requirements identification, traceability and change management.

Impact of Requirements Elicitation Activity on Idea Generation: A Designer Study

2014 ◽  
Author(s):  
Shraddha Joshi ◽  
Joshua D. Summers
Keyword(s):  
Conceptual Design ◽  
Idea Generation ◽  
Requirements Elicitation ◽  
Design Stage ◽  
Problem Statement ◽  
Requirement Elicitation ◽  
Senior Design ◽  
Potential Benefits ◽  
Design Students ◽  
The Impact

This paper presents the findings from an empirical designer study conducted with senior design students to understand the impact of requirement elicitation activity on idea generation. The participants were divided in three groups. The experiment conditions were (1) requirements elicitation (given only problem statement), (2) partial elicitation (given problem and five requirements) and (3) no elicitation (given problem and ten requirements). Participants in the first two conditions were challenged with eliciting requirements first. All participants were also asked to generate solutions. Comparing the requirements addressed in the solutions generated by the participants, it is found that the group that was not primed with the task of eliciting requirements performed better in terms of addressing requirements when compared to other two groups. These findings lead to the inference in conceptual design stage that allowing the students to elicit requirements does not have significant potential benefits while addressing the requirements.

scholarly journals An Analysis Tool for the Conceptual Design of High-Lift Systems

2021 ◽  
Author(s):  
William J.M. Bissonnette
Keyword(s):  
Conceptual Design ◽  
Analysis Tool ◽  
High Lift ◽  
Induced Drag ◽  
Multiple Data ◽  
Robust Model ◽  
Conceptual Design Phase ◽  
Wake Interactions ◽  
Wake Model ◽  
The Impact

An aerodynamic analysis tool for the conceptual design of high-lift devices has been developed. The method employs a higher-order potential ow method that uses elements of distributed vorticity. The subsequent numerically robust model allows for strong wake interactions, even when using a relaxed wake. The method predicts lift and induced drag values that compare well with multiple data experiments, and, when implemented in a panel code, maximum lift predictions of a high-lift system are found with an error of 6% from experimental data. This method is used to assess the impact that various wake models have on lift and induced drag predictions. This study shows that significant errors can be introduced when employing a prescribed wake model set to extreme angles. Compared to an approach using CFD, the computational expense of these models is relatively low. A single analysis requires minutes, making these models suitable for the iterative conceptual design phase

Multi-Objective Design Problem of Tire Wear and Visualization of Its Pareto Solutions2

2006 ◽  
Vol 34 (3) ◽  
pp. 170-194 ◽  
Author(s):  
M. Koishi ◽  
Z. Shida
Keyword(s):  
Inverse Problems ◽  
Conceptual Design ◽  
Dimensional Space ◽  
Design Stage ◽  
Objective Functions ◽  
Pareto Solutions ◽  
Design Problems ◽  
Multi Objective ◽  
Design Engineers ◽  
Design Variables

Abstract Since tires carry out many functions and many of them have tradeoffs, it is important to find the combination of design variables that satisfy well-balanced performance in conceptual design stage. To find a good design of tires is to solve the multi-objective design problems, i.e., inverse problems. However, due to the lack of suitable solution techniques, such problems are converted into a single-objective optimization problem before being solved. Therefore, it is difficult to find the Pareto solutions of multi-objective design problems of tires. Recently, multi-objective evolutionary algorithms have become popular in many fields to find the Pareto solutions. In this paper, we propose a design procedure to solve multi-objective design problems as the comprehensive solver of inverse problems. At first, a multi-objective genetic algorithm (MOGA) is employed to find the Pareto solutions of tire performance, which are in multi-dimensional space of objective functions. Response surface method is also used to evaluate objective functions in the optimization process and can reduce CPU time dramatically. In addition, a self-organizing map (SOM) proposed by Kohonen is used to map Pareto solutions from high-dimensional objective space onto two-dimensional space. Using SOM, design engineers see easily the Pareto solutions of tire performance and can find suitable design plans. The SOM can be considered as an inverse function that defines the relation between Pareto solutions and design variables. To demonstrate the procedure, tire tread design is conducted. The objective of design is to improve uneven wear and wear life for both the front tire and the rear tire of a passenger car. Wear performance is evaluated by finite element analysis (FEA). Response surface is obtained by the design of experiments and FEA. Using both MOGA and SOM, we obtain a map of Pareto solutions. We can find suitable design plans that satisfy well-balanced performance on the map called “multi-performance map.” It helps tire design engineers to make their decision in conceptual design stage.

PENGARUH KUALITAS PELAYANAN DAN KEPERCAYAAN TERHADAP LOYALITAS NASABAH PT BANK MANDIRI,Tbk CABANG JAKARTA KELAPA GADING BARAT

2015 ◽  
Vol 3 (3) ◽  
Author(s):  
Imam Wibowo ◽  
Santi Putri Ananda
Keyword(s):  
Linear Regression ◽  
Service Quality ◽  
Multiple Linear Regression ◽  
Analysis Tool ◽  
Positive Contribution ◽  
Homogeneous Population ◽  
Independent Variables ◽  
Research Population ◽  
The Impact

Purpose-To study the impact of the service quality and trust on customers loyalty of PT.Bank Mandiri,Tbk; Kelapa Gading Barat Branch. To improve the customers loyalty there are several factors that can influence them, such as service quality and trust. Methodology/approach-The research population was all customers PT.Bank Mandiri,Tbk;Kelapa Gading Barat Branch.According to the homogeneous population and based on the Gay and Diehl Theory, the samples taken were 50 people. Variables in this investigations consisted of: a).Independent Variables (exogenous): Service Quality (X1) and Trust (X2). b).The dependent variable (endogenous) Customers Loyalty (Y). Analysis tool being used is multiple linear regression which previously conducted validity and realiability. Findings-The result of investigations that service quality and trust simultaneously have a very strong contribution of 75,5% to the customers loyalty, and partially showed that service quality has significant and positive contribution to the customers loyalty of 64,8%. Partially, the trust variable has significant and positive contribution which amounted to 55,9% to the customers loyalty.

scholarly journals A Rational Numerical Method for Simulation of Drop-Impact Dynamics of Oleo-Pneumatic Landing Gear

2021 ◽  
Vol 11 (9) ◽  
pp. 4136
Author(s):  
Rosario Pecora
Keyword(s):  
Numerical Method ◽  
Initial Conditions ◽  
Impact Load ◽  
Numerical Models ◽  
Landing Gear ◽  
Design Stage ◽  
Impact Dynamics ◽  
State Variables ◽  
Adopted Model ◽  
The Impact

Oleo-pneumatic landing gear is a complex mechanical system conceived to efficiently absorb and dissipate an aircraft’s kinetic energy at touchdown, thus reducing the impact load and acceleration transmitted to the airframe. Due to its significant influence on ground loads, this system is generally designed in parallel with the main structural components of the aircraft, such as the fuselage and wings. Robust numerical models for simulating landing gear impact dynamics are essential from the preliminary design stage in order to properly assess aircraft configuration and structural arrangements. Finite element (FE) analysis is a viable solution for supporting the design. However, regarding the oleo-pneumatic struts, FE-based simulation may become unpractical, since detailed models are required to obtain reliable results. Moreover, FE models could not be very versatile for accommodating the many design updates that usually occur at the beginning of the landing gear project or during the layout optimization process. In this work, a numerical method for simulating oleo-pneumatic landing gear drop dynamics is presented. To effectively support both the preliminary and advanced design of landing gear units, the proposed simulation approach rationally balances the level of sophistication of the adopted model with the need for accurate results. Although based on a formulation assuming only four state variables for the description of landing gear dynamics, the approach successfully accounts for all the relevant forces that arise during the drop and their influence on landing gear motion. A set of intercommunicating routines was implemented in MATLAB® environment to integrate the dynamic impact equations, starting from user-defined initial conditions and general parameters related to the geometric and structural configuration of the landing gear. The tool was then used to simulate a drop test of a reference landing gear, and the obtained results were successfully validated against available experimental data.

Sign in / Sign up

Export Citation Format

Share Document