Design and Analysis of an Example Lathe Spindle

This paper discusses the modeling and analysis of an example medium speed medium precision lathe spindle. This and few other similar topics have been assigned as term projects in an introductory senior undergraduate/graduate level finite element analysis course taught at Kettering University. The experiences and the general feedback from the students of the class show satisfactory organization of the course material that includes modeling and analysis of real life examples. With reference to the specific topic on design of machine tool spindles, it is not a new area, however, it is generally taught at the graduate and research levels. Use of modern computational tools to perform iterative design and analysis calculations of such spindles make the senior undergraduate and/or graduate master students aware of the implications of modeling a real life system using the 1D and 3D finite beam elements and to validate those results by a CAE tool. Final course projects such as this serve as a good learning tool to the graduating engineers. Sample results obtained from various CAE tools such as UG-NX 7.5 are presented in the paper and discussed.

Numerical Simulation as in Integral Component of Dynamics Problem Solving

The engineering faculty at Roger Williams University are committed to training students to use modern computer-based tools when performing engineering analysis. But achieving this is a tall order, as engineering courses are already jam-packed with essential technical material and any hindrance to delivering this material is unwelcome. Likewise, we routinely pay lip service to the necessity for students to double-check their work, yet we provide students with few tools for systematically accomplishing this. This paper describes an effort by the author to integrate solid modeling into a Dynamics course by requiring numerical validation of symbolic solutions to homework problems. The students solve traditional homework problems using free-body diagrams, equations of motion, pencils and calculators; but then must demonstrate that their answers are valid through an independent check. Students construct solid models in SolidWorks© to duplicate the geometric and inertial properties of the problem, and then use the Motion Analysis, a SolidWorks Simulation add-in, to create a motion study duplicating the conditions of the problem. Students may place dynamically updating dimensions to determine distances or may generate graphs, e.g. velocity versus time, to study motion characteristics. As a direct result, students are able to independently validate their symbolic solutions with numerical simulations. This paper will provide a detailed description of the use of SolidWorks in a sophomore level Dynamics course offered spring 2012 and spring 2013. This paper will present examples of student work and assess the benefits and challenges associated with this teaching method.

Design, Machining and Production Integration Problems in Manufacturing Automation

This paper describes the process of integrating engineering design, manufacturing, and production in the area of manufacturing automation. The work was done within the scope of a Mechanical Engineering senior course that’s objective was to introduce students to the processes of advanced manufacturing and to solving practical engineering problems in manufacturing automation. The students’ efforts at integration covered automation of conceptual and geometric designs, automation of machining process, and machine sequence optimization. The CAD/CAM software, CAMM3 Micromodeler, G-code, NX8, Solid Works, DELMIA/QUEST, and Mastercam were used successfully in a sequence. A survey of the students’ opinions about the effectiveness and user friendliness of the software was summarized at the end of the semester. The elements of the course were integrated in the Final Project. Full automation of integrated design and manufacturing data exchange were found to be too difficult to accomplish. However, the use of the automation software in a sequence, together with data export and import, marks a significant step forward towards integrated manufacturing automation. The research to accomplish this will continue and the results will be applied in order to reinforce the teaching and practice of Manufacturing Automation.

A Component-Centric Approach to Structural Analysis of Mechanisms

Structural analyses of mechanisms with components that move relative to each other provide a unique problem to the analyst building and running structural models. In these situations, the analyst usually has to either simplify the problem to a point where the results are unusable or maintain multiple models, which will take more effort to maintain and more resources to run the models. If a mechanism is simplified down to just analyzing one component at a time without regard for the other components in the system, the results will not be accurate because the loading effects of the other components will not be accounted for. In cases where all the components are included in the model the loading effects from the other components will be accounted for, however, a separate model will be required for each position. This paper presents a method of breaking down the complex mechanism into a component level model for each part of the assembly, while still accounting for all loading effects of the other components; in the Pivot Method the component under analysis stays stationary and the loading moves around the component to represent the different positions that it can take. In order to accomplish this task, a simplified model is used to generate loads at each of the joints. Once the pivot loads are known, a spreadsheet can be used to transform the loads to a coordinate system in which the individual component is being modeled. With the pivot loads known and all the loads transformed into the proper coordinate system the structural analysis of the component under investigation can continue. The intention of this paper is to introduce the Pivot Method and to demonstrate that it provides a good trade off between both the complexity of methods that model the assembly as a system, and those that focus on the component under question alone. To accomplish this, the analysis results of the Pivot Method models will be compared to results obtained from other methods, with the intention of showing that the Pivot Method will provide the same results while requiring less effort to model and less resources to run.

Development of a Laboratory Equipment for Dynamic Systems and Process Control Education

This paper addresses the development of an equipment to teach control engineering fundamentals. The design requirements were determined by users that perform academic, research and industrial training tasks in the area of dynamic systems and process control. Such requirements include: industrial instrumentation; measurement of controlled and manipulated variables, and disturbances; process reconfigurability; different control technologies; several control strategies; appropriate materials for visualization; and compact shape to optimize lab space. The selected process is a tank system that allows one to choose among several dynamic behaviors: first, second, and third order, linear and nonlinear behavior, and dead time; the mathematical model that represents the dynamics of the system is presented. A traditional 3-stage design methodology that includes conceptual, basic and detailed design was followed. The developed equipment allows the user to select from three different technological alternatives to control the system: a PLC, an industrial controller, and a computer. With such flexibility, several control strategies can be implemented: feedback, feedforward, PID, LQG, nonlinear control (gain scheduling, sliding mode, etc.), fuzzy logic, neural networks, dynamic matrix control, etc. The developed system is being used to teach undergrad courses, grad courses, and industrial training. Additionally, the equipment is useful in research projects where grad students and researches can implement and test several advanced control techniques.

Utilizing Schlieren Imaging to Visualize Heat Transfer Studies

Convective heat transfer beyond explicit solutions to the Navier Stokes equations is often an empirical science. Schlieren imaging is one of the only fluid imaging systems that can directly visualize the density gradients of a fluid using collimated light and refractive properties. The ability to visualize fluid densities is useful in both research and educational fields. A Schlieren imaging device has been constructed by undergraduate students at the University of Portland. The device is used for professorial heat transfer and fluid dynamics research and to help undergraduates visualize and understand natural convection. This paper documents the design decisions, design process, and the final specifications of the Schlieren system. A simple 2-D heated cylindrical model is considered and evaluated using Schlieren imaging, OpenFOAM C.F.D. simulation, and convection analysis using a Nusselt correlation. Results are presented for the three analysis techniques and show excellent verifications between the CFD simulation, Nusselt correlation, and Schlieren imaging system.

Transformation of an Aviation Turboshaft Engine Into a Experimental Jet Engine for Laboratory Testing Unstable Radial Compressor Work

The article deals with the use of a small aviation turboshaft engine for laboratory purposes. This study describes its transformation into an experimental device for research and education. Various constructional, technological and controlling modifications and settings of the gas turbine test stand were carried out and tested on a stationary configuration. The stationary system can be used as a small backup power generator or as a drive unit for a compressor, pump, etc. New control systems, electronic elements and methods of measuring rotations, pressure and temperature are tested for educational and research purposes. The study includes a schematic description of modelling measurements and subsequent numerical evaluation of the thermodynamic characteristics of the cycle in an experimental gas turbine. The laboratory device presented here is, thanks to technological, material and thermodynamic research, suitable for educating and testing the knowledge of future aviation and mechanical engineers. The content of the article is a description of the use of transformed small turboshaft engine into small jet engine by means of experimental testing of unstable work of the radial compressor under laboratory conditions.

Study of the Change of Performance of an Elastic Vertical Hydrofoil With Deformation

In external and internal fluid flow analysis using numerical methods, most attention is paid to the properties of the flow assuming absolute rigidity of the solid bodies involved. However, this is often not the case for water flow or other fluids with high density. The pressure forces cause the geometry to deform which in turn changes the flow properties around it. Thus, a one-way and two-way Fluid-Structure Interaction (FSI) coupling is proposed and compared to a CFD analysis of a windsurfing fin in order to quantify the differences in performance data as well as the properties of the flow. This leads to information about the necessity of the use of FSI in comparison to regular CFD analysis and gives indication of the value of the enhanced results of the deformable analysis applied to water flow around an elastically deformable hydrofoil under different angles of attack. The performance data and flow property evaluation is done in ANSYS Fluent using the k-ω SST and k-ε model with a y+ of 1 and 35 respectively in order to be able to compare the behavior of both turbulence models. It is found that the overall lift coefficient in general is lower and that the flow is less turbulent because of softer transition due to the deformed geometry reducing drag forces. It is also found that the deformation of the tip of the hydrofoil leads to vertical lift forces. For the FSI analysis, one-way and two-way coupling were incorporated leading to the ability to compare results. It has been found that one-way coupling is sufficient as long as there is no stall present at any time.

Implementation of Multi-Year Product Innovation Projects

A methodology and case study detailing the implementation of multi-year product innovation projects is presented. A product called the Waterboy, an inexpensive water purification system designed for under developed countries, was developed by three different groups of students over a span of two years. The initial concept was first developed by a six member entrepreneurial team composed of senior level business and engineering students enrolled in a one semester Product Innovation and Development course. This team was responsible assessing the market need, determining product requirements and developing a limited functionality prototype capable of demonstrating the intended product function. A second team consisting of two Mechanical Engineering students continued the project as their one semester Senior Capstone Design project and was charged with the task of developing a fully functional prototype capable of purifying contaminated water. A third student completed the project as a one semester senior level Design Projects course and was charged with the task of modifying the previous design to minimize cost, facilitate ease manufacture and reduced assembly and distribution costs. In the Fall of 2010, the entrepreneurial team conducted interviews with health professionals and performed research involving a number of world health and philanthropic organizations. They identified the need for an improved water purification device which could purify enough water for a family of four in a reasonable amount of time and at a cost which would make it accessible to people in underdeveloped countries who are at risk of dying from the consumption of contaminated drinking water. They developed a bicycle driven system which used an ultraviolet germicidal bulb to purify water. The team developed a prototype which demonstrated the basic function of the device which was estimated to cost about $80. The project was continued in the Fall of 2011 by the second team of Mechanical Engineering seniors who refined the purification system and function of the device while simplifying the design, resulting in an estimated cost of $49 per unit. The team built and tested a fully functional prototype which confirmed it was capable of reducing water borne bacteria by a factor of 1000. The project was then completed in the Fall of 2012 by a Senior Mechanical Engineering Student who further reduced the cost of the design and improved its portability in order to reduce distribution costs. A partnership with Goodwill Industries was formed to utilize their recycled materials and inexpensive labor force, which reduced the product cost about $24.

Assessing Remote Physiological Signals Acquisition Experiments

A great number of remote laboratories has been implemented in the engineering field. Nevertheless, there are few approaching the bioengineering area. The present paper will describe not only an innovative remote laboratory developed for biomedical engineering education, but also its assessment based on the target public’s feedback. The remote laboratory developed by the research team intends to provide the physiological signals remote acquisition from human body, supported by theory to a greater understanding of learned concepts. This tool is geared towards the undergraduate biomedical engineering students. Therefore, a sample of twelve students took part in a limited study conducted to quantitatively and qualitatively assess the remote laboratory. The study was undertaken using two questionnaires, one distributed before and other after the performance of a remote experiment. Moreover, the information about the learning style/method, employed by each student, was collected in order to devise strategies for future applications development and to make the remote laboratory suitable for the target public.