Support Layout Research Articles

Simple Support Layout Optimization Method for Vacuum Insulation Panels (VIPs) for Refrigerators

We propose an analysis technique to support the layout optimization of the vacuum insulation panels (VIPs) for refrigerators. We used a one-dimensional calculation technique to simulate the heat loss caused by VIP envelope materials. The VIP thermal characteristics were shown by approximated system efficiency by using the panel's average length (Lp). We compared this simplified method to three dimensional numerical analysis on 1-6 micrometer thick, vacuum-packed aluminum foil and 1.5 6 mW/mK of thermally conductive heat-insulated core materials. The heat loss generated by the proposed method was verified to with a 1% error margin.

Optimization of support positions to minimize the maximal deflection of structures

In this paper, the design sensitivity analysis for the deflection of a beam or plate structure is first investigated with respect to the position of a simple support using the discrete method. Both elastic and rigid supports are taken into account, and closed-form formulae for the deflection sensitivity are developed straightforwardly. Then, on the basis of the design sensitivity analysis, a heuristic optimization algorithm, called the evolutionary shift method, is presented for support position optimization to minimize the maximal deflection of a structure with a fixed grid mesh scheme. In each iterative loop, the support with the highest efficiency is shifted in priority. To facilitate the convergence of the process, a polynomial interpolation technique is employed to evaluate the solution more accurately. The optimal solution is achieved gradually with a minimum modification of the support layout design. Finally, three numerical examples are presented to demonstrate the validities of the sensitivity analysis and the optimization method. Results show that support optimization can improve the structural behavior significantly.

Optimization of fixture design with consideration of thermal deformation in face milling

Abstract Effective methods of fixture design are proposed to reduce machining error caused by cutting heat in face milling. Experiments show that thermal effect is critical to final error in the finish cut and that it dominates cutting accuracy. Therefore, a mathematical model is structured of the cutting heat source on behalf of the cutting tool, and the flatness error generation process in face finishing is demonstrated by computational simulation based on the moving cutting heat source model with FEM. Concerning surface flatness due to the moving cutting heat source for relatively thin plate-shaped workpieces, different methodologies have been proposed to reduce flatness error, namely, the application of additional supports and optimization of the fixturing support layout. Cutting experiments and computational analyses show the effectiveness of the additional supports and the optimization methodology applied on the fixture design in view of flatness error due to cutting heat. The proposed methodologies are applicable and beneficial to improve cutting accuracy not only of plate-shaped workpieces but also of other geometry workpieces.

Compliance based MIP model and heuristic for support layout optimization

Machining-fixture supports are used to increase workpiece rigidity. A critical problem of machining fixture design is where to place a fixed number of supports in order to minimize the affect of workpiece deformation on machined feature geometric error during machining. In a previous effort, a linear Mixed Integer Programming (MIP) model was developed to solve this problem. This model is based upon a statically reduced FEA model of the workpiece, and is capable of solving the more general problem of locator button-support layout. A major disadvantage of this model is that its size is sensitive to the square of the number of machining response points considered. Since the difficulty of solving an MIP model increases with model size, this presents a severe limitation to the use of the MIP model in applications in which a large number of machining response points must be considered. This paper illustrates a technique that can be used to make the MIP model size strictly proportional to the number of machining response points. In addition, it presents a heuristic based on the MIP model, that can be used to solve support layout problems of any size.

Fast support layout optimization

Machining-fixture supports are used to increase workpiece rigidity. A critical problem of machining-fixture design is where to place a fixed number of supports in order to minimize workpiece deformation during machining. This paper presents the Fast Support Layout Optimization (FSLO) model. The objective of the FSLO model is to determine support locations that will minimize the maximum displacement-to-tolerance ratio of a set of workpiece features subject to a system of machining loads. The FSLO model utilizes a Finite Element Analysis (FEA) model to characterize workpiece stiffness. Solution of the FSLO model improves an existing support layout by systematically altering the boundary conditions applied to the FEA model. The FSLO model is unique in that its solution time is both very small and insensitive to the size of the FEA model, the sizes of machined features considered, and the sizes of the candidate regions of the supports. In addition to describing the formulation of the FSLO model, this paper describes a set of experiments that were used for its verification.

Development of an educational facilities layout software

Abstract This paper describes a software developed for educational purposes that integrates most required procedures in design of facilities layout. It can be used to explain the steps that have to be taken in facilities planning process. The input for this program include: history of demand for the products to be manufactured, bill of materials, route sheets, elements of cost, type of layout desired, type of material handling system preferred, inventory policies implemented, and financial status of the company. The output of the program include: production capacity, number of equipment, number of skilled and unskilled labor, production cost of the product, layout of the production, service, and support facilities, size and layout of receiving and shipping, the size and layout of the storage and warehouse, number of material handlers, total area required, total capital invested and/or borrowed, and financial report.

Prediction of convergence and layout of stonedrift supports (In German) : te Kook, J Gluckauf-forschungsh V47, N3, June 1986, P112–119

Prediction of convergence and layout of stonedrift supports (In German) : te Kook, J Gluckauf-forschungsh V47, N3, June 1986, P112–119

A Systems Analysis of Fast Manned Flights to Venus and Mars—Part I: Mission Philosophy, Life Support, Scientific Reconnaissance, and Prototype Vehicle Layout

A Systems Analysis of Fast Manned Flights to Venus and Mars—Part I: Mission Philosophy, Life Support, Scientific Reconnaissance, and Prototype Vehicle Layout