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Mathematical simulation of heat generation at a cutting-tool surface during stock removal processes

Mzad Hocine

Engineering Transactions

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2021

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Vol. 69, iss. 4

423--436

EN

The heat generated in various cutting zones significantly influences machining, affects tool wear, and thereby reduces tool life. In this paper, a spline cubic interpolation is used to estimate the transient heat flux imposed on the surface of a carbide cutting tool during stock removal, at constant thermal properties and cutting velocity. Interpolation of instantaneously measured temperature data set by the polynomial of lowest possible degree that passes through the points of the dataset is obtained. A high-precision remote-sensing infrared thermometer is used to measure the temperature at the surface. For friction shear stress determination, a mounted sensing system detects strain gauges signals and computes them in the form of forces on the display screen. From thermal behavior point of view the final result is notably interesting: it highlights the feature of non-proportionality in temperature/heat flux variation.

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Study of mechanical behaviour in three-point bending of fatigue-stressed composite laminates

Khelifa Noureddine, Bey Kamel, Mzad Hocine

Composites Theory and Practice

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2021

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R. 21, nr 3

107--113

EN

The aim of this work was to conduct an experimental investigation of the mechanical behaviour in the three-point bending of fatigue-stressed cross-ply laminated composites. A 3-point static bending study was carried out on two types of laminated composite materials to determine their mechanical characteristics as well as to assess the influence of the test speed and the effect of the stacking sequence on their mechanical behaviour. Different damage modes leading to the rupture of these materials were highlighted to determine their types.

3

Simulation of photovoltaic panel cooling beneath a single nozzle based on a configurations framework

Mzad Hocine, Otmani Abdessalam

Archives of Thermodynamics

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2021

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Vol. 42, no 1

115--128

EN

Solar cell performance decreases with increasing temperature, heat can reduce output efficiency by 10–25%. The operating temperature plays a key role in the photovoltaic conversion process. Increase in electrical efficiency depends on cooling techniques, in particular photovoltaic modules installed in the high temperature regions. A cooling process using a single nozzle of photovoltaic panel operating under different configurations was simulated. The simulation contains two parts: the first is a thermodynamic investigation of fluid impingement upon the sensor front face. The second is a performance comparison between two types of glass cover. The major result that emerges from this simulation is the effect of a single nozzle arrangement to enhance the cooling process, under a low cadence of impinging droplets in the range 0.1–1.7 m/s.

4

Thermal simulation of a continuous casting process subjected to water-sprays cooling

Mzad Hocine, Otmani Abdessalam

Archives of Thermodynamics

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2020

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Vol. 41, no 2

185--199

EN

As in many thermal processing technologies, there is a delicate balance between productivity and quality during ingot cooling process. Higher cooling velocities increase productivity but also create higher temperature gradients inside the ingot. Such a fast cooling does not leave sufficient time to establish the equilibrium within the solid, thus the final metal structure is strongly affected by the set up cooling mode throughout the liquid metal solidification. The first intention in this paper is to compare between three cooling modes in order to identify the required mode for a continuous casting process. Then, we study the influence of heat transfer coefficient on metal liquid-to-solid transition through the spray-cooled zone temperature and the metal latent heat of solidification. A gray iron continuous casting process subjected to water-sprays cooling was simulated using the commercial software for modeling and simulating multiphysics and engineering problems. The primary conclusions, from the obtained results, show the forcefulness of water spray cooling regarding standard cooling. Afterward, we highlight the great influence of heat transfer coefficient on the location of transition region as well as the relationship between heat transfer coefficient, wall outer temperature, latent heat dissipation, and the solidification time.