Machinery Course Research Articles

Computer-Aided Teaching Using MATLAB/Simulink for Enhancing an IM Course With Laboratory Tests

This paper describes an automatic procedure using MATLAB software to plot the circle diagram for two induction motors (IMs), with wound and squirrel-cage rotors, from no-load and blocked-rotor tests. The advantage of this approach is that it avoids the need for a direct load test in predetermining the IM characteristics under reduced power. Additionally, to verify the validity of the equivalent circuit parameters deduced from experimental tests, these characteristics are used to simulate virtual machines implemented under Simulink/PSB models. Furthermore, a virtual load test is performed to validate the proposed model. Finally, the results are given of an assessment that reflects the positive impact the proposed methods have had on students' learning experience in electrical machinery courses in the Electrotechnics Department, Engineer Sciences Faculty, University Mentouri of Constantine (ED-ESF-UMC), Algeria.

Development and Assessment of a Prototype as an Innovative Method for Teaching Agricultural Machinery

An educational variable-rate application (VRA) sprayer was developed and laboratory tested at the University of Seville (Spain). It was designed and built during 2009 by the undergraduate engineering students in a Precision Agriculture course and used as a teaching model in an Agricultural Machinery course during 2010. The first stage involved mounting all the instrumentation, sensors, and the hydraulic system on a metal platform. The second stage involved mounting a DGPS receiver, flowmeter, automated application control system, and all necessary electrical connections to the platform. Preliminary calibration tests of the equipment at a constant speed of 0.375 m s-1 (1.35 km h-1) showed good performance for pressure (kPa) and application rate (L ha-1) (R2 = 0.998, p < 0.001). To evaluate the teaching method based on the prototype, a short-answer assessment test was conducted consisting of ten multiple-choice questions, each with one possible correct answer. Data were analyzed using analysis of variance (ANOVA). The factors were the teaching method (TM), repeated course (R), and attended theory (AT). In addition, the effect of a covariate (number of times a student repeated the course) in the factors was controlled with an analysis of covariance (ANCOVA). The effect of teaching method was significant for the score on the VRA sprayer questions (SPS) variable and the score on the conventional sprayer questions (SCS) variable (p < 0.001 for both). The average success for students using the prototype sprayer was 86%, compared to 60% for those using a conventional sprayer. The total cost of the VRA prototype sprayer was 40% less than the cost of retrofitting a conventional sprayer with precision agriculture equipment. Since the students were engaged in their own learning, they maintained a high level of enthusiasm throughout the course when utilizing the VRA prototype sprayer. It has proved to be a complementary and beneficial alternative for improving the students' education in the Agricultural Machinery course.

Adding the Teaching of Claw Rotor Compressors to Fluid Machinery Courses

This paper deals with a rotary positive-displacement machine with built-in compression, the study of which is usually neglected in courses on fluid machinery for mechanical engineering students. First, the working principles of the claw rotor compressor are presented; then basic thermodynamic considerations, leading to the formulation of volumetric efficiency, are reported. The volumetric efficiency of the compressor is reviewed as a function dependent on filling and leakages, leading to the definition of the delivery efficiency. Considering the filling efficiency alone, formulated according to a thermodynamic analysis of the closed system, it is possible to determine the limit pressure ratio that causes no flow from the compressor. The ideal work is also formulated and a comparison with the sliding vane compressor is made. Some considerations that deprive the compressor of its ideality are advanced in order to avoid misleading conclusions.

A learning methodology using Matlab/Simulink for undergraduate electrical engineering courses attending to learner satisfaction outcomes

Learner-centred approaches follow the prevailing tendency in modern University reforms which are primarily concerned about “how people learn”. The methodologies can be learner-centred in the sense of placing the student as the main actor of the teaching–learning process by increasing his interactivity and participation, but also considering what is relevant for the student by measuring the learner satisfaction. In order to promote both aspects, this paper proposes a synchronous software-based active methodology that makes use of the simulations to show a virtual scenario to the students and challenge them to predict and discuss the evolution of the scenario. The proposed methodology improves the visual interface, promotes discussion both among students and with the teacher in a brainstorming stage and shows real-world examples. This software-based methodology has been implemented into an Electric Machinery course at the University of Seville (Spain), and the evaluation has been carried out considering both the affective and cognitive domains. Principal components analysis proves to be useful to highlight the dimensions with a higher influence on learner satisfaction and the affective and cognitive results confirm the successful implementation of the proposal.

DC motor speed control methods using MATLAB/Simulink and their integration into undergraduate electric machinery courses

AbstractThis paper describes the MATLAB/Simulink realization of the DC motor speed control methods, namely field resistance, armature voltage and armature resistance control methods, and feedback control system for DC motor drives. These simulation models are developed as a part of a software laboratory to support and enhance undergraduate electric machinery courses at Nigde University, Nigde, Turkey. © 2007 Wiley Periodicals, Inc. Comput Appl Eng Educ 15: 347–354, 2007; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20151

Restructuring an Electric Machinery Course With an Integrative Approach and Computer-Assisted Teaching Methodology

The course of Electric Machinery has been one of the core courses in the Electrical Engineering (EE) curriculum at Texas A&M University-Kingsville (TAMUK). In the past, the course was designed to focus mainly on topics of transformers and electric machines and was typically presented under the assumption of steady-state conditions. Unfortunately, many students considered the course old-fashioned and unexciting, and this lack of interest, in turn, seriously limited their ability to understand and appreciate the wide-ranging applications of electric machines. More important, electric machines today have become widely integrated with power electronics, digital signal processing (DSP), and digital control technology. However, these technological changes were not adequately reflected in the traditional teaching structure of the course. This paper presents a new approach that, by integrating computer-assisted teaching methodology in classroom presentation, substantially restructures the course so that it provides a comprehensive treatment of electric-drive systems with discussions covering electric machines, power electronic converters, feedback controls, power supply systems, and mechanical systems.

Transformer tests using MATLAB/Simulink and their integration into undergraduate electric machinery courses

This article describes MATLAB/Simulink realization of open-circuit and short-circuit tests of transformers that are performed to identify equivalent circuit parameters. These simulation models are developed to support and enhance electric machinery education at the undergraduate level. The proposed tests have been successfully integrated into electric machinery courses at Drexel University, Philadelphia, PA and Nigde University, Nigde, Turkey. © 2006 Wiley Periodicals, Inc. Comput Appl Eng Educ 14: 142–150, 2006; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20077

Induction Motor Tests Using MATLAB/Simulink and Their Integration Into Undergraduate Electric Machinery Courses

This work describes MATLAB/Simulink implementation of three induction motor tests, namely dc, no-load, and blocked-rotor tests performed to identify equivalent circuit parameters. These simulation models are developed to support and enhance electric machinery education at the undergraduate level. The proposed tests have been successfully integrated into electric machinery courses at Drexel University, Philadelphia, PA, and Nigde University, Nigde, Turkey.

Electrical Machinery in an Electronics-Oriented Curriculum

Revision of the electrical machinery courses requires the selection of those concepts fundamental to the field and a studied organization and presentation of these concepts in a form which correlates with other courses in the curriculum (particularly in the method of approach to analysis) and which simultaneously provides motivation in the form of interesting examples and illustrations drawn from current technological frontiers. The paper describes briefly one such attempt, in which the emphasis is placed on electromechanical signal transducers and their description in terms of two-port network functions, linear incremental models, and transfer functions.