Jean Brousseau

Modeling and Sensitivity Study of the Induction Hardening Process

Induction heating is a case hardening process used to improve performance of machine components by producing a hard martensitic microstructure and high compressive residual stresses at the surface layer. A reliable numerical model able to predict the hardness profile would shorten process development. However, the accuracy and the efficiency of the model are restricted by the coupling complexity between the electromagnetic and thermal fields, and the nonlinear behaviour of the material properties. The paper analyzes the sensitivity of the material properties values and of the finite element meshing onto the predictive modeling of the case hardening profiles. The material used is SAE-4340 low-alloy steel. The simulations are done using a computer-modeling software (Comsol) and the sensitivity analysis is conducted by using an experimental design method.

Study of induction heating process applied to internal gear using 3D model

The current paper is principally dedicated to the study of geometry and frequency effects for internal spur gears heated by induction. The overall work is realized by the simulation efforts performed on Comsol multi-physics software. The 3D model used during this study is built basing on coupling between Maxwell’s and heat transfer equations. This model is used to calculate the temperature profile in the gear in function of machine parameters. The module and the frequency are varied to determinate their effects. In fact, two gears having the same external diameter but different modules are exploited during this study and the frequency is varied from low to high level. The obtained results allow understanding the effect of module and frequency on the final temperature distribution. Finally, the optimal frequency value permitting to have the best temperature profile is found.

Explorative Study and Prediction of Overtempering Region of Disc Heated by Induction Process Using 2D Axisymmetric Model and Experimental Tests

Thanks to many industrial benefits that it exhibits, induction heating process is very promising for its potential application in manufacturing production. To understand the industrial context, it is necessary to investigate the process by focusing on simulation and experimental aspects. In fact, this paper presents an original approach able to predict the overtempering zone with analyzing the temperature curves resulting from simulationand the hardness profile achieved by experimental validation. The proposed approach combines experimental validation and numerical simulation applied to 4340 steel disc in order to investigate the overtempering phenomenonand develop a very simplified and practical model able to predict the hardness curve with a fairly good accuracy. The developed model is validated by experimental tests and is used to evaluate the effect of machine parameters on the overtempering.

Sensitivity Study of Temperature Profile of 4340 Spur Gear Heated by Induction Process Using 3D Model

This paper presentsa sensitivity study using a Comsol3D model simulation for spur gear heated by induction process. Based on an adequate formulation and taking into account the material properties, a multi-physics 3D model is built to calculate the final temperature distribution determinate according the machine parameters and some geometrical factors (coil width and gap between coil and gear). Since the hardness profile is affected by thermal historic during heating, the surface temperatures are deeply analyzed versus the initial current density and the heating time using medium (MF) and high frequencies (HF). Finally, the sensitivity of hardness profile with the machine parameters variation isinvestigated using various statistical tools applied to the obtained results. The obtained results exhibits the main machine parameters and theirs effects on the hardness profile.

Natural Ventilation of Smoke Subject to Wind Pressure Within Fire Safety Engineering Approach

This paper presents an analytical model able to explore the design method of natural smoke evacuation through an exhaust vent subject to wind pressure. The proposed model can be used to determine the flow rate of smoke and the optimal section of the exhaust vent according to the geometric parameters of the room, the heat release rate and the pressure exerted by the wind forces at the exhaust vent. The numerical resolutions of the mathematical equations of the model were performed using the dichotomy method. The proposed analytical approach is built progressively by, (i) the examination of interaction forces between buoyancy forces and wind pressure forces, (ii) a numerical validation of the analytical model using the numerical simulation software Fire Dynamics Simulator, and (iii) proposal of a method of approximation of the optimal section of the exhaust vent for a maximum smoke evacuation rate. The results show very satisfactory and provide adequate prediction of the optimal size of the exhaust vent between the theoretical approximation and various configurations of numerical simulation. The feasibility and effectiveness of the proposed approach lead to an accurate and reliable analytical model able to analyze the influence of the size of natural smoke evacuation vents subjected to the pressure of wind forces.

Laboratory Activities in Industrial Sequential Automation through a Virtual and Physical Environment

 Abstract—The present project is intending as a new training approach based on the communication technology and the interaction between future engineers and technicians students. The first phase of the global project was consisted of developing of an automated mini-plant for containers recycling process and was realized by engineering students attending the project-based design courses. The second phase is consisting in development of the virtual environment allowing interactions between the students and between the students and the mini-plant. A laboratory activity has been conducted on the modules of the mini-plant. Future engineers and technicians have the mission to design, program and troubleshoot while they are working simultaneously. The obtained results demonstrate that the engineers and technicians students communicate effectively but they have different skills and competences. The training objectives have been achieved and the learned lessons will be exploited to enhance the training level and the competences in the future. engineers and technician to rapid technological changes in automation systems. A relevant solution can be based on training by providing required skills to future engineers and technicians training. In fact, their academic contents also have to be constantly modernized to track current technologies and future trends. Aware to the training quality, the Universite du Que bec a Rimouski (UQAR), the Ce gep de Rivie re du-Loup (CEGEP) and the Premier Tech Company (PTS), a world leader in the bagging equipment field, have decided to join forces in order to improve the training of future engineers and technicians in Industrial Automation field.

Effect of Skin Depth on Hardness Profile of Gear Heated by Induction Using 2D Model

This work is carried principally by simulation efforts using computer-modeling software (COMSOL). The developed 2D model includes the coupling between electromagnetic and thermal fields, and takes account of the nonlinear behaviour of material properties versus temperature. Several steps were followed to reach this goal. First, a 2D finite element model of a gear was developed in order to simulate the induced currents density and temperature distributions for various frequencies and external currents applied in the coil. Second, the temperature profiles were compared using the ratio between the skin depth and the teeth height. In geometry cases, it was possible to dose the power level of the medium (MF) and high (HF) frequencies to reach a desired uniform case depth. The MF and HF powers are simulated sequentially in order to better concentrate heat in the tooth tip and root of gear. The obtained results help process developers to select the proper parameters for the induction machine in order to achieve the desired hardness profile.

Effects of Material Properties for Non-Equilibrium Conditions in Induction Heating Process

As the induction heating is very fast, it is reasonable to assume that the material properties are different from those measured under thermodynamic equilibrium conditions. For this reason, this study attempts to measure the effect of material properties variations on the surface temperature using the 2D axisymmetric model. The results show that the relative magnetic permeability is the property that most significantly influences surface temperatures and the hardness profile. The effects of specific heat and electrical conductivity are rather low, while the thermal conductivity has a negligible effect on the model developed. Moreover, the variation ofaustenitizingtemperature of margins has limited effects on the developed model. Therefore, the use of material properties at thermodynamic equilibrium was sufficient to establish models able to predict trends.

Design System Assessment Tool

In 2010, an exploratory survey focused on design methods, tools and techniques, was conducted in order to understand what type of design practices are used in Small and Medium-sized Enterprises (SMES) located in Eastern Quebec. This study reveals that most SMEs declared using a structured design process while very few are regular users of structured Methods, sophisticated Tools, or specialized design Techniques (MTT). Because the results suggest that the design process in SMEs is not as structured as could be expected a new research was launched. Specifically, the research objective consist to identify the most important determinants of design performance and to develop indicators for assessing the design process as well as the other dimensions of design projects. In this model, six dimensions describe what is called the design system: the environmental dimension, the human and techno-scientific axis, management, the design process and the product aspects. The Dimensions are evaluated using an assortment of variables (descriptors) to assess the “design system” of an organization. Each descriptor is related to the following issues: (i) the type of methods, tools and activities used by the organization, (ii) the importance of the descriptor according to the project success, (iii) the performance level of the organization in that matter and (iv) the involvement of the partners. The questionnaire has been tested and refined on a pilot basis by eight partners. In addition to the model and the questionnaire, the paper presents an overview of the survey results and it illustrates how the assessment tool can be used to identify the challenges that a company must face in order to improve its design practices. Finally, it exposes the strengths and weaknesses of the questionnaire and it identifies the improvements to be made before to use it as base of an observatory intended to measure and monitor the evolution of design practices of organizations.

Effect of Dimensional Variation on Induction Process Parameters Using 2D Simulation

The induction heating is a surface heat treatment that exhibits some relevant industrial advantages. In fact, the process is not energy-consuming compared to thermo-chemical processes such as carbonizing and nitriding because it allows generating high power and focusing it locally and during a short time to achieve hardness at the surface area without affecting the part core. Using no plating phase, the induction heating process is qualified as green and sustainable manufacturing process but should be better understood to help developers to reach optimized recipes in a small number of process iterations. Globally, for a given range of parts to be manufactured, one has to proper select the frequency and power of the equipment to be. This work will show how part geometry, generator frequency and power are closely linked. This work is carried principally by simulation efforts using computer-modeling software (COMSOL). A developed 2D model includes the coupling between electro-magnetic and thermal fields, and takes account of the non-linear behavior of material properties versus temperature. The simulation allows optimizing the machine according to the dimensions of gear. This paper also proposes a method to approximate the power amount required to achieve a desired hardness profile.