bluuebunny/crossref_metadata_2025_split huggingface dataset:
Finite Element Technique for the Curved Beam Analysis: In-Plate Vibration of Curved Beam With Varying Cross Section
Authors: Tanaka Michihiko , Kobayashi Motoki 
Published: April 2021

Abstract
The purpose of this paper is to present details of an algorithm for performing the numerical analysis of in-plane free vibration problem of curved beam by using the finite element technique. Although the finite element techniques for the straight or flat structures such as rods, beams and plates are well established, the finite element formulation for curved beam has not yet been completely discussed because of analytical complexity of the beam. The analysis of curved beam is reduced to the coupled problems of the axial and the transverse components of forces, bending moments, displacements and slopes in the beam. Sabir and Ashwell have discussed the vibrations of a ring by using the shape functions (interpolation functions) based on simple strain functions[1]. The discrete element displacement method was applied to the vibrations of shallow curved beam by Dawe[2]. Suzuki et al have presented the power series expansions method for solving free vibration of curved beams[3]. Irie et al have used spline functions to analyse the in-plane vibration of the varying cross section beams supported at one end[4].
Editing of Finite Element Models
Authors: Lundgren Gert M. 
Published: April 2021

Abstract
Meshing of complex shapes is often performed automatically with many of todays preprocessors. However in the case where the mesh has to be modified locally, the analyst needs tools that can conveniently be applied to individual elements. One reason for this may be the need to apply an external load at a specific location. Another reason may be that a local cutout has to be reflected, or a transition from a coarse to a finer mesh is needed. This paper discusses the design and usage of such tools, in the following referred to as ‘Micro-Editing’ tools.
Automatic Mesh Generation of Complex Hollow Structures via Substructuring Into Box-Like Components
Authors: Abhary Kazem 
Published: April 2021

Abstract
A method has been developed for finite element modelling of complex hollow structures. The structure is first simulated as a number of simple box-like substructures, then the finite element mesh is generated in each substructure, and finally the finite element model of the whole structure is built up through coupling the components together. An example has been illustrated by applying the method to the structure of a milling machine, which as a hollow structure is sufficiently complex.
Description of an Interface Between MSC/NASTRAN and MATRIXx With Example Applications
Authors: Morrison Scot , Caffrey John 
Published: April 2021

Abstract
This paper describes an existing interface which allows extraction of linear models from an MSC/NASTRAN output file and conversion into MATRIXX readable format for control design and simulation. The interface is demonstrated using an MSC/NASTRAN model of a satellite microwave antenna.
In addition to the existing interface, a proposed expanded interface allowing additional information to be transfered between MSC/NASTRAN and MATRIXX is presented. Candidate information includes component mass and stiffness matrices, and outputs from MSC/NASTRAN’s Design Sensitivity Analysis (DSA) package. This sensitivity data would allow open or closed loop robustness analysis, and simultaneous structural and controller design. Additionally, the ability to transfer linear controllers designed in MATRIXX to MSC/NASTRAN would allow evaluation of such controllers on the full order model.
Upgrades for Engineering Software
Authors: Hadjistylianou Marinos , Hoffman Daniel 
Published: April 2021

Abstract
Improvements in hardware and software technology offer exciting opportunities for software development in the 1990’s. Nonetheless, because wholesale replacement of large systems is rarely feasible, most computing in the 90’s will be done by way of improving software written in the 70’s and 80’s. Consequently, methods for incremental improvement are critically needed. We propose software upgrades, in which improvements in internal system structure are scheduled with each user request for new features or error removal.
Reduction of Vehicle Interior Noise Using Our New Structural-Acoustic Sensitivity Analysis Methods
Authors: Hagiwara Ichiro , Kozukue Wakae , Ma Zheng-Dong 
Published: April 2021

Abstract
Since interior noise has a strong effect on vehicle salability, it is particularly important to be able to estimate noise levels accurately by means of simulation at the design stage. The use of sensitivity analysis makes it easy to determine how the analytical model should be modified or the structure optimized for the purpose of reducting vibration and noise of the structural-acoustic systems.
The present work focused on a structural-acoustic coupling problem. As the coefficient matrices of a coupled structural-acoustic system are not symmetrical, the conventional orthogonality conditions obtained in structural dynamics generally do not hold true for the coupled system. To overcome this problem, the orthogonality and normalization conditions of a coupled system were derived by us. In this paper, our sensitivity analysis methods are applied to an interior noise problem of a cabin model. It will be shown how a sensitivity analysis process is performed, and how vibration and noise can be reduced.
Active Control of a Plate Using Segmented Distributed Sensors and Actuators: Finite Element Development and Analysis
Authors: Tzou H. S. , Bahrami H. 
Published: April 2021

Abstract
Distributed sensing and control of flexible structures have drawn much attention in recent years. Piezoelectric elements can be used with an elastic structure as sensors and actuators for structural monitoring and control applications. This paper presents a development of a thin piezoelectric finite element applied to active control of flexible structures. A piezoelectric finite element is derived using the variational equation and Hamilton’s principle. System equations of a piezoelectric structure are formulated accordingly. Guyan’s reduction technique is incorporated to improve the computation efficiency. Feedback control algorithms are also derived and implemented in the finite element code. Applications of the technique to a plate with segmented distributed sensora/actuators are studied and effectiveness evaluated.
Finite Element Analysis of Turbine Blades
Authors: Carnero A. , Kubiak J. , López A. 
Published: April 2021

Abstract
Frequent failures of long turbine blades forced an electrical utility to sponsor research work to find out the causes of the failures. One of the techniques applied in this work was finite element analysis.
The paper presents an application of the finite element method for computation of the natural frequencies, steady-state and alternating stresses, deformations due to forces acting on the blades and modal shapes of the turbine long blade groups. Two stages, L-1 and L-0 of the low pressure part of a steam turbine, were analyzed.
It has been postulated that the results of the FEM analysis of the blades groups would be complementary to those obtained from the radio telemetry test (which was carried out during operation of the turbine) for the purpose of blade group failure diagnosis. However, the results of the analysis show that the FEM results were decisive in blade failure identification (L-1 stage moving blades).
The graphical post processor of the FEM code revealed that the first blade in the group was the one most protruding from the stage rotating plane, thus indicating that this blade was the most prone to erosion. This was confirmed in the inspection of the turbine. This finding showed why only the first blade in the group was cracked (erosion induced cracks). The mode shapes were also very helpful in identifying other types of cracks which affected other parts of the blades.
It can be concluded that the finite element method is very useful for identification of very difficult cases of blade faults and indispensable for carrying out modifications to prevent future failures.
Finite Element Mesh Generator Applying Constraints’ Propagation and Isoparametric Mapping
Authors: Rodriguez J. , Him M. 
Published: April 2021

Abstract
This paper presents a finite element mesh generation algorithm (PREPAT) designed to automatically discretize two-dimensional domains. The mesh generation algorithm is a mapping scheme which creates a uniform isoparametric FE model based on a pre-partitioned domain of the component. The proposed algorithm provides a faster and more accurate tool in the pre-processing phase of a Finite Element Analysis (FEA).
A primary goal of the developed mesh generator is to create a finite element model requiring only essential input from the analyst. As a result, the generator code utilizes only a sketch, based on geometric primitives, and information relating to loading/boundary conditions. These conditions represents the constraints that are propagated throughout the model and the available finite elements are uniformly mapped in the resulting sub-domains.
Relative advantages and limitations of the mesh generator are discussed. Examples are presented to illustrate the accuracy, efficiency and applicability of PREPAT.
Computer-Aided Geometry Design of Trapezoidal Threaded Variable Pitch Conical Lead Screws
Authors: Liu Jen-Yu , Yan Hong-Sen 
Published: April 2021

Abstract
Based on conical screw matrix transformation, equations of variable pitch conical helix and helicoid are derived. The surface geometry of a trapezoidal threaded variable pitch conical lead screw is generated by a trapezoid with a variable pitch conical screw motion. A computer-aided design code is developed with Patran Plus solid modeling. The result of this work is necessary for the computer-aided machining of trapezoidal threaded variable pitch conical lead screws.
Line Integral Computation of Geometrical Properties of Plane Faces and Polyhedra
Authors: Wilson H. B. , Chang G. S. 
Published: April 2021

Abstract
Surface integrals arising during computation of geometrical properties of volumes are studied. Line integrals are formulated which give the contributions of a general plane surface area. These integrals are evaluated to provide more concise exact formulas for the geometrical properties of polyhedra than have been obtained previously. A short computer program for polyhedron properties is presented, along with numerical examples.
Incorporating Solid Modeling Into Engineering Curriculum
Authors: Pao Y. C. 
Published: April 2021

Abstract
Solid modeling is proposed as an integral part of freshman teaching on engineering drafting, computer programming, and computer-aided design. A low-cost, commercially available software, SilverScreen, is recommended for the students to experiment on wireframe and solid modelings. In addition to providing the basic drafting needs of dimensioning, labelling text of various size and orientation, chamfering, and filleting, other topics of solid modeling are proposed for the higher-level engineering courses. It enables the students to apply multiple-view, split-screen display (such as showing the top, front, right-side, auxiliary, and section views all on one screen), and Boolean manipulation of solids (union, subtraction, and others). Moreover, students can also use SilverScreen in conjunction with other programs written in BASIC and C languages.
Computer-Aided Design of Bicycles
Authors: Khosrowjerdi M. , Azar Robert C. , Salehi Ali , Nazari G. H. 
Published: April 2021

Abstract
Traditional manual designing of bicycles often relies on prototype building and testing and since structural deficiencies often are not obvious until a prototype fails, several build-and-test iterations are usually required before a satisfactory design is obtained. Also, the final design may be less than optimal because of quick fixes inserted at the last minute. However, by utilizing computer-aided design, better bicycles can be designed at smaller investments of time and money.
The development and utilization of a DI-3000 based (graphics subroutines developed by Precision Visual), user-friendly, self contained computer aided design package for the analysis and design of bicycle frames and forks are presented. The software, written in Fortran 77 and executable on most passive and active graphics devices, creates the necessary analysis input files for the ANSYS finite element program (developed and marketed by Swanson Analysis System Inc.). These pre and post processing files in conjunction with the ANSYS program are used to determine deflections and stress components. The graphics user interface module of the software allows users to enter bicycle geometry, loading and other pertinent data quickly and efficiently. Tubing configuration and specifications are selected from a data base through the use of cursor-controlled menus. The loading menu presents users with seven different types of realistic and self-consistent loading conditions from which to choose. Computer graphics is also used extensively wherever appropriate to enhance user-computer interaction. Contrasting color and text size are used to explain pictorially as well as visually unfamiliar terminology and to clarify vague sign or orientation conventions, thus, leading to more accurate input.
While this package has been designed for instructional purposes, it can also be used by design engineers involved in the design of bicycles to facilitate the creation of ANSYS pre and post processing files.
Teaching Computer-Based Data Acquisition Through an Airfoil Experiment
Authors: Yip T. Gary 
Published: April 2021

Abstract
This paper describes a three-week long project for teaching microcomputer-based data acquisition. The project is part of a senior level laboratory course for mechanical engineering students at Santa Clara University. The subject of investigation is the lift coefficient of an airfoil.
Students in groups of two carried out the project in three phases. The laboratory activities in each phase are designed to provide the students hands-on experience with the basic functions, hardware and software of a microcomputer-based data acquisition system. Typical results obtained by the students are presented. The project has been proved to be successful for the students to learn and practice the three basic concepts in data acquisition which are measurements, controls and programming.
Developing a CAD Tutorial Using Hypermedia Concepts
Authors: Cwiakala Martin , Stamp Scott 
Published: April 2021

Abstract
This paper presents implementation of techniques formerly developed by one of the authors (Cwiakala) to create an interactive CAD tutorial for students. By using the hypermedia concept of command buttons, students can maneuver through the tutorial by following a “default path”, or jump to a specific point of interest. The knowledge required to work the tutorial is minimal. By developing the tutorial directly within the CAD package, commands may be tested at any time during the tutorial session. CAD software requirements are specified. Students were surveyed on their opinion regarding the tutorial and its supporting documentation. Strong points as well as weak are presented, and alternative methods of creating a tutorial are also discussed.
Computer Modeling of Flow Through Engineering Devices: Exercises for the Undergraduate Student
Authors: Bazaar J. J. , Shanebrook J. R. 
Published: April 2021

Abstract
The purpose of this paper is to describe four computer exercises that have been developed for undergraduate engineering students at Union College. Each exercise involves a computer model for predicting steady, viscous flow through an engineering device. All of the analyses were performed using FLUENT, a finite-difference fluid modeling program marketed by Creare, Inc. The following cases are described in this paper:
1. The flow through a square-edged orifice was modeled and results for discharge coefficient are compared with experimental data published by the American Society of Mechanical Engineers (ASME).
2. The flow through a quadrant-edged orifice was modeled and results for discharge coefficient are compared with published data.
3. The flow through a Herschel-type Venturi meter was calculated and results for discharge coefficient are compared with ASME data.
4. The flow through a sudden pipe expansion was modeled and results for head loss are compared with a theoretical model.
Development of an Integrated Simulation and Experimentation Approach to Engineering Education
Authors: Buffinton Keith W. , Baish James W. , Moffitt James H. 
Published: April 2021

Abstract
Many universities currently make extensive use of computer simulations in the teaching of undergraduate courses in engineering. This paper considers the proper role of computer simulations in an engineering curriculum and suggests that simulations alone do not provide the fundamental understanding of physical systems required of practicing engineers. An alternate approach in the use of simulations in engineering education is under development at Bucknell University that integrates both the computational and the laboratory experiences of students. This integration is achieved through the creation of a laboratory environment that provides both the computational hardware and software for preforming sophisticated simulations of various engineering systems and the physical hardware needed to verify the simulations. The unique aspect of this environment is the emphasis on the interactive integration of the computational and experimentation experiences of the student, thereby allowing them both to quickly see the limits of their simulations and to gain a firsthand understanding of the actual performance of complex physical systems.
Optimum Design of a Bipedal Walking Robot
Authors: Martin Karen , Reuber Mark 
Published: April 2021

Abstract
This paper describes the design, fabrication, and testing of “Bigfoot,” a bipedal walking machine designed to optimize speed, cost, and ease of assembly. Bigfoot walks at near-human walking speed (0.24 m/s), can be assembled/disassembled in two hours, and has a programmable, computer-controlled start-up procedure. Design for manufacturing and assembly techniques (DFMA) were used to reduce the final weight of the robot to 12 kg, the number of structural parts to 39 individual pieces held together with 50 fasteners, and the final robot cost to $300.
Combustion Modelling to Evaluate Turbulent Burning Velocities During Spark Ignition Engine Combustion
Authors: James E. H. 
Published: April 2021

Abstract
“Phenomenological” computer models of the spark ignition engine combustion process are predominantly used in a “predictive” mode i.e. the modeller develops the computer program by utilising the best current understanding of phenomena associated with the process. Thus, suitable expressions are incorporated to depict turbulent burning velocity, heat exchange with the surroundings, flame pattern development, exhaust emissions etc.. The accuracy of the model is then tested by subsequent comparison with pertinent “global” engine performance parameters such as pressure-time diagrams, average flame speeds and exhaust emissions. The “predictiveness” of the model arises from the inclusion of the turbulent burning velocity expression and assumed flame pattern development. These are notoriously difficult to specify precisely and resort is often made to generalised approximations. Thus, turbulent burning velocity is frequently accounted for by the use of expressions developed from experiments on dissimilar engine designs or even “out-of-engine” flames. Accurate flame pattern development is an equally unknown quantity since it is influenced by turbulence and swirl levels, combustion chamber surface temperatures and design, mixture homogeneity etc.. These difficulties are invariably overcome by subsuming them in a general inaccurate assumption that the flame development is spherical in nature and centred at the spark plug. Even though the “global” computer model predictions may be acceptably accurate with such assumptions, it is highly unlikely that the detailed flame progression across the chamber is modelled correctly. To overcome such criticisms, the computer model can be used in a different operational mode (1) with the ultimate aim of more precise specifications of turbulent burning velocity and how it varies across the combustion chamber.
Computer Modeling, Simulation, and Validation at FMC
Authors: Fatemi B. , Wiederrick J. 
Published: April 2021

Abstract
Increasing performance requirements of present and future mechanical systems, along with the development of cost effective high performance computers, is creating an environment where new designs require the support of numerical simulations to be successful both technically and commercially. This new design environment requires an integrated systems approach to design with more exhaustive and accurate engineering analyses being made earlier, faster, and at reduced cost and physical risk. The use of analysis in design provides better prototypes, and the same computer models provide a basis for properly interpreting/understanding empirical results. The combined effect is a shorter development cycle and a superior product based on well understood principles.
FMC, because of its diversified product lines has recognized this need and has been developing verified numerical simulation tools in support of design activities. The overall objective has been to develop verified modeling and numerical simulation capabilities to predict the performance of a total mechanical system. Our approach is to incrementally develop, validate, and integrate subsystem models into a total system level model that includes all significant subsystem interactions. Hardware and software tools for computer graphic rendering, test data acquisition, reduction, and comparison are also being developed that facilitate our goals. This presentation will provide a summary of our computer simulation and validation activities in areas of finite element techniques, kinematic and dynamic analyses, vehicle systems analysis, computer-aided testing, interactive simulation, dynamic modeling using symbolic code generation, high-performance computing, and scientific visualization.
A Least-Squared Optimization Approach to the Design of Belleville Springs
Authors: Shoup Terry E. , Sanchez Lilia 
Published: April 2021

Abstract
Belleville spring washers, also known as coned-disk springs were patented in France by Julien Belleville in 1867 and were the topic of a fundamental engineering study by Almen and Laszlo in 1936. The main advantage to these devices is their compactness and their ability to handle large loads. The deflection of these springs has been found to be nonlinear and stiffening springs have been shown to be quite useful for the design of vibration isolation mounts where combined vibration and shock loading are present. It is the purpose of this investigation to demonstrate the use of the method of least-squares optimization to design Belleville springs having prescribed load-vs-deflection performance behavior.
Monte Carlo Simulations of Two and Three Dimensional Fluids Revisited: A Successful Demonstration of the Use of Polar Coordinates
Authors: Conlan Francis J. 
Published: April 2021

Abstract
Standard Monte Carlo (MC) simulation techniques in current use (Valleau and Whittington, Valleau and Torrie, 1977) in the study of Statistical properties of fluids are limited to being performed in rectangular coordinates and rely on a non-physical construct called virtual images. Virtual imaging was a technique used in the early days of computer simulations (1950–1960) to reduce extraneous boundary effects in Monte Carlo simulations of fluids (Wood, 1968). Simulations were restricted to rectangular sampling regions providing the central sampling area with virtual images of itself. All particles, including those near the boundary, by other particles.