Discussion: “Three-Dimensional Variation Diagrams for Control of Calculations in Optimum Design” (Johnson, R. C., 1967, ASME J. Eng. Ind., 89, pp. 391–397)

This paper presents and illustrates a graphical technique for the control of calculations in the procedure of optimum mechanical design. This three-dimensional variation diagram technique minimizes the number of calculations required for the determination of the optimum design, and the general technique is applicable to many problems. Specific practical examples are given for the optimum design of a torsion bar and for the optimum design of a gearset.

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Optimization of the Wrist Pin End of an Automobile Engine Connecting Rod With an Interference Fit

Journal of Mechanical Design ◽

10.1115/1.2912622 ◽

1990 ◽

Vol 112 (3) ◽

pp. 406-412 ◽

Cited By ~ 7

Author(s):

Vijay Sarihan ◽

Ji Oh Song

Keyword(s):

Finite Element ◽

Optimum Design ◽

Three Dimensional ◽

Stress Singularity ◽

Design Strategy ◽

Structural Components ◽

Connecting Rod ◽

Fem Model ◽

Automobile Engine ◽

Interference Fit

Current design procedures for complicated three-dimensional structural components with component interactions may not necessarily result in optimum designs. The wrist pin end design of the connecting rod with an interference fit is governed by the stress singularity in the region where the wrist pin breaks contact with the connecting rod. Similar problems occur in a wide variety of structural components which involve interference fits. For a better understanding of the problems associated with obtaining optimum designs for this important class of structural interaction only the design problems associated with the wrist pin end of the rod are addressed in this study. This paper demonstrates a procedure for designing a functional and minimum weight wrist pin end of an automobile engine connecting rod with an interference fit wrist pin. Current procedures for Finite Element Method (FEM) model generation in complicated three-dimensional components are very time consuming especially in the presence of stress singularities. Furthermore the iterative nature of the design process makes the process of developing an optimum design very expensive. This design procedure uses a generic modeler to generate the FEM model based on the values of the design variables. It uses the NASTRAN finite element program for structural analysis. A stress concentration factor approach is used to obtain realistic stresses in the region of the stress singularity. For optimization, the approximate optimization strategy in the COPES/CONMIN program is used to generate an approximate design surface, determine the design sensitivities for constrained function minimization and obtain the optimum design. This proposed design strategy is fully automated and requires only an initial design to generate the optimum design. It does not require analysis code modifications to compute the design sensitivities and requires very few costly NASTRAN analyses. The connecting rod design problem was solved as an eight design variable problem with five constraints. A weight reduction of nearly 27 percent was achieved over an existing design and required only thirteen NASTRAN analyses. It is felt that this design strategy can be effectively used in an engineering environment to generate optimum designs of complicated three-dimensional components.

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A Three-Dimensional Analysis of Thermohydrodynamic Performance of Sector-Shaped, Tilting-Pad Thrust Bearings

Journal of Lubrication Technology ◽

10.1115/1.3254625 ◽

1983 ◽

Vol 105 (3) ◽

pp. 406-412 ◽

Cited By ~ 30

Author(s):

Kyung Woong Kim ◽

Masato Tanaka ◽

Yukio Hori

Keyword(s):

Dimensional Analysis ◽

Environmental Conditions ◽

Three Dimensional ◽

Two Dimensional ◽

Thrust Bearings ◽

Tilting Pad ◽

Dimensional Variation ◽

Lubricant Viscosity

The thermohydrodynamic performance of the bearing is analyzed, taking into account the three-dimensional variation of lubricant viscosity and density. The effect of pivot position and operating and environmental conditions on the performance is studied. The present analysis is compared with the isoviscous or the two-dimensional analysis, and is found to predict the bearing performance more accurately.

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Optimum design of a three-dimensional serial robot manipulator

Structural Optimization ◽

10.1007/bf01195942 ◽

1999 ◽

Vol 17 (2-3) ◽

pp. 172-185 ◽

Cited By ~ 3

Author(s):

J. A. Snyman ◽

F. Tonder

Keyword(s):

Optimum Design ◽

Robot Manipulator ◽

Three Dimensional ◽

Serial Robot

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Three‐dimensional variation of the slab geometry within the South American subduction system

Geophysical Research Letters ◽

10.1029/2021gl095924 ◽

2022 ◽

Author(s):

Meng Liu ◽

Haiying Gao

Keyword(s):

Three Dimensional ◽

South American ◽

The South ◽

Slab Geometry ◽

Dimensional Variation ◽

Subduction System

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Three-dimensional optimum design of the cooling lines of injection moulds based on boundary element design sensitivity analysis

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1243/09544050260174265 ◽

2002 ◽

Vol 216 (7) ◽

pp. 1067-1071 ◽

Cited By ~ 4

Author(s):

H Zhou ◽

D Li ◽

S Cui

Keyword(s):

Sensitivity Analysis ◽

Objective Function ◽

Boundary Element ◽

Optimum Design ◽

Three Dimensional ◽

Design Sensitivity ◽

Boundary Integral ◽

Optimization Techniques ◽

Design Sensitivity Analysis ◽

Design Variables

A three-dimensional numerical simulation using the boundary element method is proposed, which can predict the cavity temperature distributions in the cooling stage of injection moulding. Then, choosing the radii and positions of cooling lines as design variables, the boundary integral sensitivity formulations are deduced. For the optimum design of cooling lines, the squared difference between the objective temperature and the temperature of the cavity is taken as the objective function. Based on the optimization techniques with design sensitivity analysis, an iterative algorithm to reach the minimum value of the objective function is introduced, which leads to the optimum design of cooling lines at the same time.

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