Multidisciplinary Design And Optimization Research Articles

AGILE Paradigm: The next generation collaborative MDO for the development of aeronautical systems

The research and innovation EU funded AGILE project has developed the next generation of aircraft Multidisciplinary Design and Optimization (MDO) processes, which target significant reductions in aircraft development costs and time to market, leading to more cost-effective and greener aircraft solutions. 19 industry, research and academia partners from Europe, Canada and Russia have developed solutions to cope with the challenges of collaborative design and optimization of complex aeronautical products. In order to accelerate the deployment of large-scale, collaborative multidisciplinary design and optimization, a novel approach, the so-called “AGILE Paradigm”, has been conceived. The AGILE Paradigm is defined as a “blueprint for MDO”, accelerating the deployment and the operations of collaborative “MDO systems” and enabling the development of complex products practiced by multi-site and cross-organizational design teams, having heterogeneous expertise. A set of technologies has been developed by the AGILE consortium to enable the implementation of the AGILE Paradigm principles, thus delivering not only an abstract formalization of the approach, but also an applicable framework. The collection of all the technologies constitutes the so-called “AGILE Framework”, which has been applied for the design and the optimization of multiple aircraft configurations. The ambition of the AGILE Paradigm was set to reduce the lead time of 40% with respect to the current state-of-the-art. This work reviews the evolution of the MDO systems, underlines the open challenges tackled by the AGILE project, and introduces the main architectural concepts behind the AGILE Paradigm. Thereafter, an overview of the application design cases is presented, focusing of the main challenges and achievements. The AGILE technologies enabled the consortium to formulate and to solve in 15 months 7 MDO applications in parallel for the development of 7 novel aircraft configurations, demonstrating time savings beyond the 40% goal.

Trimaran Structural Weight Optimization Based on Classification Rules

Structural optimization is one of the important aspects of the overall ship design process. A number of advanced optimization tools are available. As these tools require large computational resources, they are not suitable for use in the preliminary design stages, when many important aspects of the design, such as overall dimensions and hull configurations, are determined. This article describes the development of an efficient structural weight optimization method for a trimaran hull form within the governing rules and regulations of the classification society. The method is particularly useful in the early design stage because of its simplicity. Two trimaran hull forms (HSTT-180 and TriFerry) are selected and optimized using the multi-island genetic algorithm optimization process. The weight optimization process achieved a weight reduction for HSTT-180 and TriFerry of about 32.85% and 8.95%, respectively. Furthermore, in both cases, optimum structural weights were obtained with smaller values of main-hull and side-hull stiffener spacing but higher values of main-hull frame spacing. Results obtained indicate that the structural weight of trimaran designs, such as those referenced here, can be substantially reduced by advanced optimization methods. 1. Introduction High-speed ships are of increasing interest for diverse applications, including military and commercial purposes. Hydrodynamic requirements for many high-speed concepts can only realistically be addressed by multihull designs since multihull ships provide better performance than monohull ships at high speeds. Trimaran hull form vessels, in particular, can offer several favorable characteristics over comparable monohulls, including fuel efficiency and the possibility of superior seakeeping characteristics (Fuentes et al. 2015). Trimarans are designed as Ro-Ro and passenger ships, ferries, containers, and military vessels. Multidisciplinary design and optimization (MDO) of trimarans, particularly at the synthesis design level, is an active area of research (Hefazi et al. 2010, 2011). A major element of the MDO process is the development of a structural optimization subsystem to investigate the impact of variations in vessel configurations on structural design and weight. A number of advanced analysis tools for calculation of structural weight are available. However, these tools require large computational resources and time and as such are not suitable to use in the preliminary design stages. Ironically, that is when many important aspects of the design, such as overall dimensions and hull configurations, are often determined. Therefore, an efficient method for calculation of structural weight, and its integration in an automated optimization process, is highly desirable and is the focus of this article. This approach allows structural weight optimization to be included in determining important principal characteristics of the ship at the early stage of the design.

Concept Development of Design Driven Parts Regarding Multidisciplinary Design Optimization

ABSTRACTThe increasing number of derivates in the automotive sector, combined with the product variation for individualization and technical progress, is presenting a major challenge for product designers. There are many case studies, especially in the concept development, which need to be checked on feasibility. This paper outlines how the necessary efficiency improvement, to deal with the rising amount of projects, can be achieved through the application of a Knowledge Based Engineering System (KBES). A special focus is put on the automated construction of design driven components. Furthermore, possibilities for the integration of expert knowledge into the construction system are demonstrated in order to enable a single user to build a product model according to the methodology of Multidisciplinary Design and Optimization (MDO).An approach for the knowledge based creation of automotive headlamps is presented in detail. The advantages of a reacting construction system consisting of a variety of construct...

An Airplane Calculator Featuring a High-Fidelity Methodology for Tailplane Sizing

ABSTRACT: The present work is concerned with the accurate modeling of transport airplanes. This is of primary importance to reduce aircraft development risks and because multi-disciplinary design and optimization (MDO) frameworks require an accurate airplane modeling to carry out realistic optimization tasks. However, most of them still make use of tail volume coefficients approach for sizing horizontal and vertical tail areas. The tail-volume coefficient method is based on historical aircraft data and it does not consider configuration particularities like wing sweepback angle and tail topology. A methodology based on static stability and controllability criteria was elaborated and integrated into a MATLAB application for airplane design. Immediate advantages with the present methodology are the design of realistic tail surfaces and properly sized airplanes. Its validation was performed against data of five airliners ranging from the regional jet CRJ-100 to the Boeing 747-100 intercontinental airplane. An existing airplane calculator application incorporated the present tail-sizing methodology. In order to validate the updated application, the Fokker 100 airliner was fully conceptually designed using it.

Hyper Heuristic Approach for Design and Optimization of Satellite Launch Vehicle

Satellite launch vehicle lies at the cross-road of multiple challenging technologies and its design and optimization present a typical example of multidisciplinary design and optimization (MDO) process. The complexity of problem demands highly efficient and effective algorithm that can optimize the design. Hyper heuristic approach (HHA) based on meta-heuristics is applied to the optimization of air launched satellite launch vehicle (ASLV). A non-learning random function (NLRF) is proposed to control low-level meta-heuristics (LLMHs) that increases certainty of global solution, an essential ingredient required in product conceptual design phase of aerospace systems. Comprehensive empirical study is performed to evaluate the performance advantages of proposed approach over popular non-gradient based optimization methods. Design of ASLV encompasses aerodynamics, propulsion, structure, stages layout, mass distribution, and trajectory modules connected by multidisciplinary feasible design approach. This approach formulates explicit system-level goals and then forwards the design optimization process entirely over to optimizer. This distinctive approach for launch vehicle system design relieves engineers from tedious, iterative task and enables them to improve their component level models. Mass is an impetus on vehicle performance and cost, and so it is considered as the core of vehicle design process. Therefore, gross launch mass is to be minimized in HHA.

Multidisciplinary Synthesis Optimization Process in Multihull Ship Design

This paper describes the development and application of a synthesis-level multidisciplinary design and optimization (MDO) method for multihull ships. This method is unique in utilizing advanced multi-objective optimization methods, neural network (NN)-based response surface methods (RSM), and in its broad scope, integrating powering, stability, seakeeping, hullforms definition, structural weights, and cost and payload capacity into a single design tool. This MDO method is developed in the context of a multilevel hierarchy system approach where the results of the synthesis level optimization can be used for subsystem optimization and overall coordination of multilevel design system. NN-based RSM for seakeeping and powering is developed and used in the optimization process. This RSM approach moves the computational cost of such performance evaluations out of the optimization cycle, substantially reduces the optimization cost, and allows for using results of physics-based methods, such as advanced computational fluid dynamics, at the synthesis-design level of design hierarchy. Details of these methods are delineated and multi-objective optimization results are presented in the form of Pareto optimum solutions for multihull ship concepts such as trimaran sealift support ships and catamaran high-speed connector ships.

Multidisciplinary Design and Optimization of Multistage Ground-launched Boost Phase Interceptor Using Hybrid Search Algorithm

This article proposes a multidisciplinary design and optimization (MDO) strategy for the conceptual design of a multistage ground-based interceptor (GBI) using hybrid optimization algorithm, which associates genetic algorithm (GA) as a global optimizer with sequential quadratic programming (SQP) as a local optimizer. The interceptor is comprised of a three-stage solid propulsion system for an exoatmospheric boost phase intercept (BPI). The interceptor's duty is to deliver a kinetic kill vehicle (KKV) to the optimal position in space to accomplish the mission of intercept. The modules for propulsion, aerodynamics, mass properties and flight dynamics are integrated to produce a high fidelity model of the entire vehicle. The propulsion module comprises of solid rocket motor (SRM) grain design, nozzle geometry design and performance prediction analysis. Internal ballistics and performance prediction parameters are calculated by using lumped parameter method. The design objective is to minimize the gross lift off mass (GLOM) of the interceptor under the mission constraints and performance objectives. The proposed design and optimization methodology provide designers with an efficient and powerful approach in computation during designing interceptor systems.

A Systematic Approach for Quantitative Analysis of Multidisciplinary Design Optimization Framework

An efficient Multidisciplinary Design and Optimization (MDO) framework for an aerospace engineering system should use and integrate distributed resources such as various analysis codes, optimization codes, Computer Aided Design (CAD) tools, Data Base Management Systems (DBMS), etc. in a heterogeneous environment, and need to provide user-friendly graphical user interfaces. In this paper, we propose a systematic approach for determining a reference MDO framework and for evaluating MDO frameworks. The proposed approach incorporates two well-known methods, Analytic Hierarchy Process (AHP) and Quality Function Deployment (QFD), in order to provide a quantitative analysis of the qualitative criteria of MDO frameworks. Identification and hierarchy of the framework requirements and the corresponding solutions for the reference MDO frameworks, the general one and the aircraft oriented one were carefully investigated. The reference frameworks were also quantitatively identified using AHP and QFD. An assessment of three in-house frameworks was then performed. The results produced clear and useful guidelines for improvement of the in-house MDO frameworks and showed the feasibility of the proposed approach for evaluating an MDO framework without a human interference.

다분야 통합 최적설계 프레임워크 구축방법 분석

다분야 통합 최적설계(MDO) 프레임워크는 항공우주시스템의 설계에 고려해야 할 다양한 설계 분야의 통합적이고 동시적인 해석 및 설계 최적화를 위한 통합 환경으로 해석자원 및 최적화자원은 물론 CAD 툴과 DBMS 또한 통합해야하며 사용자편의환경을 제공해야한다. 또한 설계하고자 하는 대상 및 개발환경에 따라 프레임워크의 구축방법은 달라질 수 있다. 본 논문에서는 개발환경에 따라 단일 PC기반 프레임워크와 PLinda기반 프레임워크, 그리고 웹서비스 기반 프레임워크로 분류하여 이들을 비교 분석하였다. MDO(Multidisciplinary Design and Optimization) framework can be an integrated environment or a system, which is for synthetic and simultaneous analysis and design optimization in various design fields of aerospace systems. MDO framework has to efficiently use and integrate distributed resources such as various analysis codes, optimization codes, CAD tools, DBMS and etc. in heterogeneous environment, and to provide graphical and easy-to-use user interfaces. Also, its development method can be changed by design objects and development environment. In this paper, we classify MDO frameworks into three types according to the development environments: Single PC-based, PLinda-based and Web Services-based MDO framework. And, we compare and analyze these frameworks.

웹 서비스 기반 MDO 시스템

다분야 통합 최적설계(MDO)는 여러 설계분야가 복잡하게 얽혀서 설계가 진행되어야 하는 항공기나 우주발사체등의 설계에 매우 유용하게 적용되고 MDO 시스템은 다양한 설계 분야의 통합적이고 동시적인 해석 및 설계 최적화를 위한 통합 환경 또는 시스템이다. MDO 시스템은 이기종의 환경에서 분산되어있는 다양한 해석 코드 및 최적화 코드, CAD, DBMS, GUI등의 자원들을 통합하고 효율적으로 사용할 수 있어야하며 협업설계환경을 제공해야한다. 본 논문에서는 웹 서비스 기반의 글로버스 툴킷을 이용해 설계자원들을 통합하고 워크플로우, 에이전트 등의 자동화 기술을 이용해 유기적인 자동실행을 제공하며 웹 유저 인터페이스를 통해 협업설계환경을 제공하는 웹 서비스 기반 MDO 시스템의 구축방안을 제시한다. MDO(Multidisciplinary Design and Optimization) can be applied for design of complex systems such as aircraft and SLV(Space Launch Vehicle). MDO System can be an integrated environment or a system, which is for synthetic and instantaneous analysis and design optimization in various design fields. MDO System has to efficiently use and integrate distributed resources such as various analysis codes, optimization codes, CAD, DBMS, GUI, and etc. in heterogeneous environments. In this paper, we present Web Services-based MDO System that integrates resources for MDO using Globus Toolkit and provides organic autonomous execution using automation technique such as Workflow system and agent. And also, it provides collaborative design environment through web user interfaces.

Design optimization of containers for sloshing and impact

A multidisciplinary design and optimization (MDO) method is presented to support the design process of partially filled liquid containers subject to the disciplines of sloshing and impact analyses. Experimental techniques are used to understand sloshing as a phenomenon and to evaluate the computational fluid dynamics code. Validation includes qualitative comparison of visual free-surface behavior and quantitative comparisons of pressure measurements in the time and frequency domain. The liquid motion exhibits good comparisons in time. Deviations are caused by both the experimental signal filtration process and deficiencies in the low-frequency measurement capability of the accelerometer. The first two odd oscillatory modes are accurately captured. An objective function for the quantitative evaluation of the sloshing phenomenon is proposed. For impact, the von Mises baffle stress is used. Single and multidisciplinary optimization formulations using LS-OPT are presented and examined. The multidisciplinary optimum proved to be a compromise between the optima obtained when considering the two single disciplines independently.

반응모델 최적화와 설계공간 변환을 이용한 반복적 반응면 개선 기법 연구

In this study, a repetitive response surface enhancement technique (RRSET) is proposed as a new system approximation method for the efficient multidisciplinary design and optimization (MDO). In order to represent the highly nonlinear behavior of the response with second order polynomials, RRSET introduces a design space transformation using stretching functions and repetitive response surface improvement. The tentative optimal point is repetitively included to the set of experimental points to better approximate the response surface of the system especially near the optimal point, hence a response surface with significantly improved accuracy can be generated with very small experimental points and system iterations. As a system optimizer, the simulated annealing, which generates a global design solution is utilized. The proposed technique is applied to several numerical examples, and demonstrates the validity and efficiency of the method. With its improved approximation accuracy, the RRSET can contribute to resolve large and complex system design problems under MDO environment.

An interactive multiobjective optimization design strategy for decision based multidisciplinary design

This research focuses on Multidisciplinary Design and Optimization (MDO) of large scale systems that have multiple objective functions. The primary goal is to develop and test an interactive multi-objective optimization algorithm for multidisciplinary system design that takes into account the Decision Maker's (DM's) preferences during the design process. An interactive Multi-Objective Optimization Design Strategy (iMOODS) developed in Tappeta and Renaud [1-3] has been modified in this research to include a MDO algorithm to address both the multiobjective and multidisciplinary issues involved in system design. This interactive strategy (iMOODS with MDO capability) provides the DM with a formal means for efficient design exploration around a given Pareto point. The strategy has been successfully applied to two design problems which are multidisciplinary in nature and have multiple objective functions. The first problem is the design of an autonomous hovercraft system that has four complexly coupled disciplines or contributing analyses (CAs) and two objective functions. The second problem is an aircraft concept sizing problem that has three disciplines and three objective functions. The results indicate that the strategy is effective and efficient in capturing the DM's preferences and arriving at the optimum design.

Optimization of magneto-hydrodynamic control of diffuser flows using micro-genetic algorithms and least-squares finite elements

In this paper we consider the problem of multidisciplinary design and optimization (MDO) of a diffuser for a steady, incompressible magnetohydrodynamic (MHD) flow. Given a fixed diffuser shape, the optimizer should find the distribution of the wall magnets that will maximize the static pressure increase from inlet to outlet. This design problem is solved through the use of a genetic algorithm based optimization program coupled with a finite element based MHD simulation program. For MHD simulation, a least-squares finite element method (LSFEM) based program has been developed. The use of LSFEM allows the use of equal order approximation functions for all unknowns and is stable for high Reynolds numbers. Optimization was accomplished using a micro-genetic algorithm (GA) based program. The micro-GA is capable of searching the design space with a population much smaller than that required by classical GA. The optimization was performed on a parallel computer composed of commodity PC components. Results show that an applied magnetic field with the proper strength and distribution can significantly improve the static pressure rise over the case of no magnetic field.