Design Of High Speed Civil Transport Research Articles

VizCraft: a problem-solving environment for aircraft configuration design

The VizCraft problem-solving environment aids aircraft designers during conceptual design of a high-speed civil transport (HSCT). It integrates simulation codes that evaluate a design with visualizations for analyzing a design individually or in contrast to other designs. VizCraft provides a graphical user interface to a widely used suite of simulation and analysis codes for HSCT design, and it provides tools for visualizing the outputs of these codes. So, VizCraft provides an environment that combines visualization and computation, encouraging the designer to think in terms of the overall problem-solving task, not simply using the visualization to view the computation's results.

A distributed, heterogeneous computing environment for multidisciplinary design and analysis of aerospace vehicles

A framework for rapid applications development is described that implements an object-oriented computational environment in which the Common Object Request Broker Architecture and the Java programming language are used to encapsulate discipline codes as reusable “objects”. The environment exploits the parallelisms inherent in the application and distributes the disciplines on machines most appropriate to their needs, while insulating the developer and the user from the complexity of the underlying communications constructs. Data and file management are accomplished using Java's database connectivity to access a commercial relational database management system. Java's Beans Development Kit (BDK) is used to implement the disciplines and sub-tasks as reusable components and to provide a graphical interface for user input as well as to facilitate interactive and visual object connectivity and monitor problem execution progress. The advantages of this approach have been demonstrated through the implementation of a standalone aerodynamic optimizer and the analysis of a large-scale high speed civil transport design optimization problem in this framework.

Cost-Effective Multipoint Design of a Blended High-Speed Civil Transport

The multipoint design of a high-speed civil transport (HSCT) is considered. Low computational costs are maintained by parameterizing the HSCT using a novel method of surface generation known as the partial differential equation method. This method enables a reduction in the computational costs because of its ability to describe complex surfaces using a small number of parameters. The two design points that are considered are the subsonic and supersonic (Mach 2) flight regimes with design criteria of maximized lift and minimized wave drag, respectively. Subsonic lift is estimated using Panel Method Ames Research Center, whereas supersonic wave drag is estimated using the Harris wave-drag code (which is based upon linearized potential flow theory and the supersonic area rule). An efficient quasi-Newton method of optimization is used to optimize a weighted combination of subsonic lift and supersonic wave drag subject to the constraints of a fixed wing plan area and fixed fuselage and wing volumes. A variety of test problems are considered in which the weightings of the two design criteria are varied

Multidisciplinary optimisation of a supersonic transport using design of experiments theory and response surface modelling

AbstractThe presence of numerical noise in engineering design optimisation problems inhibits the use of many gradient-based optimisation methods. This numerical noise may result in the inaccurate calculation of gradients which in turn slows or prevents convergence during optimisation, or it may promote convergence to spurious local optima. The problems created by numerical noise are particularly acute in aircraft design applications where a single aerodynamic or structural analysis of a realistic aircraft configuration may require tens of CPU hours on a supercomputer. The computational expense of the analyses coupled with the convergence difficulties created by numerical noise are significant obstacles to performing aircraft multidisciplinary design optimisation. To address these issues, a procedure has been developed to create noise-free algebraic models of subsonic and supersonic aerodynamic performance quantities, for use in the optimisation of high-speed civil transport (HSCT) aircraft configurations. This procedure employs methods from statistical design of experiments theory and response surface modelling to create the noise-free algebraic models. Results from a sample HSCT design problem involving ten variables are presented to demonstrate the utility of this method.

Variable-complexity response surface approximations for wing structural weight in HSCT design

A procedure for generating and using a polynomial approximation to wing bending material weight of a High Speed Civil Transport (HSCT) is presented. Response surface methodology is used to fit a quadratic polynomial to data gathered from a series of structural optimizations. Several techniques are employed in order to minimize the number of required structural optimizations and to maintain accuracy. First, another weight function based on statistical data is used to identify a suitable model function for the response surface. In a similar manner, geometric and loading parameters that are likely to appear in the response surface model are also identified. Next, simple analysis techniques are used to find regions of the design space where reasonable HSCT designs could occur. The use of intervening variables along with analysis of variance reduce the number of polynomial terms in the response surface model function. Structural optimization is then performed by the program GENESIS on a 28-node Intel Paragon. Finally, optimizations of the HSCT are completed both with and without the response surface.

Structural weight estimation for multidisciplinary optimization of a high-speed civil transport

A variable-complexity-modeling design strategy with combined aerodynamic and structural optimization procedures is presented for the high-speed civil transport (HSCT). A finite element model-based structural optimization procedure with flexible loads is implemented to evaluate the wing-bending material weight. Static aeroelastic effects on wing-bending material weight, evaluated through the comparison of rigid and flexible wing models, are found to be small in the HSCT design. The results of structural optimization are compared with two quasiempirical weight equations. Good correlation is obtained between the structural optimization and one of the weight equations. Based on this comparison, an interlacing procedure is developed to combine both the simple weight equations and the structural optimization in the HSCT design optimization, at modest computational cost.

Variable-complexity response surface approximations for wing structural weight in HSCT design

A procedure for generating and using a polynomial approximation to wing bending material weight of a High Speed Civil Transport (HSCT) is presented. Response surface methodology is used to fit a quadratic polynomial to data gathered from a series of structural optimizations. Several techniques are employed in order to minimize the number of required structural optimizations and to maintain accuracy. First, another weight function based on statistical data is used to identify a suitable model function for the response surface. In a similar manner, geometric and loading parameters that are likely to appear in the response surface model are also identified. Next, simple analysis techniques are used to find regions of the design space where reasonable HCST designs could occur. The use of intervening variables along with analysis of variance reduce the number of polynomial terms in the response surface model function. Structural optimization is then performed by the program GENESIS on a 28-node Intel Paragon. Finally, optimizations of the HSCT are completed both with and without the response surface.