ABSTRACT One of the sources of increased industrial energy consumption is the heating equipment, ... more ABSTRACT One of the sources of increased industrial energy consumption is the heating equipment, e.g., furnaces. Their domain of use is very wide and due to its abundance of applications it is key equipment in modern civilization. The present experimental investigations are related to reducing energy consumptions and started from the geometry of a classic manufactured furnace. During this experimental study, different cases have been carefully chosen in order to compare and measure the effects of applying different enhancement methods of the radiation heat transfer processes. The main objective of this work was to evaluate the behavior of a heated enclosure, when different radiant panels were introduced. The experimental investigation showed that their efficiency was influenced by their position inside the heating area. In conclusion, changing the inner geometry by introducing radiant panels inside the heated chamber leads to important time savings in the heating process.
This paper presents experimental and theoretical studies regarding the behavior after heat treatm... more This paper presents experimental and theoretical studies regarding the behavior after heat treatment of an AlCu2Mg1,5Ni aluminum alloy. So, we selected a typical charge for studying the variation of hardness. The studies that we have done can reveal the advantage of controlling the heating process at heat treatment of aluminum alloys. Doing the studies that are described in the paper,
ABSTRACT The aim of this article is to present an experimental method to optimize the heating tim... more ABSTRACT The aim of this article is to present an experimental method to optimize the heating time in a furnace in order to show an example of the progression toward increasingly empirical solutions as the problems become progressively more unwieldy. During this experimental study, different cases are carefully chosen to compare and measure the effects of applying different enhancement methods of the heat transfer processes. It is found that changing the inner geometry by introducing radiant panels inside the heated chamber leads to important time savings in the heating process by increasing the convection rate in the furnace.
Heat transfer simulation is of great significance for the heating equipments control. In this pap... more Heat transfer simulation is of great significance for the heating equipments control. In this paper, a set of models is proposed to solve heat transfer problems in a furnace, including radiation and convection. The heat transfer models are integrated with a furnace model to simulate the heating process. The heating rate is increased due to enhanced heat transfer at the surfaces by changing furnace chamber geometry. A fixed grid enthalpy formulation is applied to model heat transfer for an oval geometry. The heating temperature was found to increase linearly with curvature of the interior.
Heat transfer simulation within heating furnaces is of great significance for prediction and cont... more Heat transfer simulation within heating furnaces is of great significance for prediction and control of the performance of furnaces. In this paper, a set of models is proposed to solve heat transfer problems in a loaded furnace. Furthermore, a 2-dimensional algorithm based on a finite difference method is presented. The heat transfer models are integrated with a furnace model to simulate the heating process of workpieces. Temperature variation of the workpiece with time is predicted by the system. An experiment is carried out for validation of the system. Themain objective of this work is to evaluate the behavior of a heated enclosure, when variable radiant panels are introduced. Experimental investigation shows that their efficiency depends on their position.
Surface Engineering and Applied Electrochemistry, 2008
This paper presents the results of experimental and theoretical studies regarding the behavior of... more This paper presents the results of experimental and theoretical studies regarding the behavior of AlCu4Mg1 aluminum alloy after a heat treatment. The methodology has been proposed to study improvements in AlCu4Mg1 aluminum alloy in the process of heat treatment, which included the following steps: (1) adopting the heat treatment technology for the specified alloy, (2) choosing the necessary heat treatment installations to perform the heat treatment of the specified alloy, (3) choosing tools and machines used to study the mechanical characteristics, and (4) planning the experiment and analytical interpretation of the results. On the basis of these experiments and the obtained regression equation, we performed a theoretical study with the aim to determine the heating parameters for quenching and aging in order to obtain a specified stress needed for application of this alloy. We considered two cases for this theoretical study: (1) the stress and quenching temperatures were fixed and we determined the aging temperature; (2) the stress and aging temperatures were fixed and we determined the quenching temperature. Using the determined equations, we assumed the definite characteristics needed for the working part after treatment and calculated the parameters for quenching and artificial aging in the process of the heat treatment. Note that the calculated temperatures should be in the standard limits for the studied alloy. In conclusion, an algorithm was proposed for the process of the optimum heat treatment in order to obtain the necessary properties of the working parts.
In order to increase the resistance of aluminium alloys a complex heat treatment is usually perfo... more In order to increase the resistance of aluminium alloys a complex heat treatment is usually performed. Therefore, we must consider the reaction time between aluminium alloys and furnace atmosphera. These atmospheres contain oxygene and nytrogene. Aluminium is an active element, therefore the oxidation is a very fast one.From the experiments made, the oxidation kinetics of aluminum alloys proves to depend
ABSTRACT One of the sources of increased industrial energy consumption is the heating equipment, ... more ABSTRACT One of the sources of increased industrial energy consumption is the heating equipment, e.g., furnaces. Their domain of use is very wide and due to its abundance of applications it is key equipment in modern civilization. The present experimental investigations are related to reducing energy consumptions and started from the geometry of a classic manufactured furnace. During this experimental study, different cases have been carefully chosen in order to compare and measure the effects of applying different enhancement methods of the radiation heat transfer processes. The main objective of this work was to evaluate the behavior of a heated enclosure, when different radiant panels were introduced. The experimental investigation showed that their efficiency was influenced by their position inside the heating area. In conclusion, changing the inner geometry by introducing radiant panels inside the heated chamber leads to important time savings in the heating process.
This paper presents experimental and theoretical studies regarding the behavior after heat treatm... more This paper presents experimental and theoretical studies regarding the behavior after heat treatment of an AlCu2Mg1,5Ni aluminum alloy. So, we selected a typical charge for studying the variation of hardness. The studies that we have done can reveal the advantage of controlling the heating process at heat treatment of aluminum alloys. Doing the studies that are described in the paper,
ABSTRACT The aim of this article is to present an experimental method to optimize the heating tim... more ABSTRACT The aim of this article is to present an experimental method to optimize the heating time in a furnace in order to show an example of the progression toward increasingly empirical solutions as the problems become progressively more unwieldy. During this experimental study, different cases are carefully chosen to compare and measure the effects of applying different enhancement methods of the heat transfer processes. It is found that changing the inner geometry by introducing radiant panels inside the heated chamber leads to important time savings in the heating process by increasing the convection rate in the furnace.
Heat transfer simulation is of great significance for the heating equipments control. In this pap... more Heat transfer simulation is of great significance for the heating equipments control. In this paper, a set of models is proposed to solve heat transfer problems in a furnace, including radiation and convection. The heat transfer models are integrated with a furnace model to simulate the heating process. The heating rate is increased due to enhanced heat transfer at the surfaces by changing furnace chamber geometry. A fixed grid enthalpy formulation is applied to model heat transfer for an oval geometry. The heating temperature was found to increase linearly with curvature of the interior.
Heat transfer simulation within heating furnaces is of great significance for prediction and cont... more Heat transfer simulation within heating furnaces is of great significance for prediction and control of the performance of furnaces. In this paper, a set of models is proposed to solve heat transfer problems in a loaded furnace. Furthermore, a 2-dimensional algorithm based on a finite difference method is presented. The heat transfer models are integrated with a furnace model to simulate the heating process of workpieces. Temperature variation of the workpiece with time is predicted by the system. An experiment is carried out for validation of the system. Themain objective of this work is to evaluate the behavior of a heated enclosure, when variable radiant panels are introduced. Experimental investigation shows that their efficiency depends on their position.
Surface Engineering and Applied Electrochemistry, 2008
This paper presents the results of experimental and theoretical studies regarding the behavior of... more This paper presents the results of experimental and theoretical studies regarding the behavior of AlCu4Mg1 aluminum alloy after a heat treatment. The methodology has been proposed to study improvements in AlCu4Mg1 aluminum alloy in the process of heat treatment, which included the following steps: (1) adopting the heat treatment technology for the specified alloy, (2) choosing the necessary heat treatment installations to perform the heat treatment of the specified alloy, (3) choosing tools and machines used to study the mechanical characteristics, and (4) planning the experiment and analytical interpretation of the results. On the basis of these experiments and the obtained regression equation, we performed a theoretical study with the aim to determine the heating parameters for quenching and aging in order to obtain a specified stress needed for application of this alloy. We considered two cases for this theoretical study: (1) the stress and quenching temperatures were fixed and we determined the aging temperature; (2) the stress and aging temperatures were fixed and we determined the quenching temperature. Using the determined equations, we assumed the definite characteristics needed for the working part after treatment and calculated the parameters for quenching and artificial aging in the process of the heat treatment. Note that the calculated temperatures should be in the standard limits for the studied alloy. In conclusion, an algorithm was proposed for the process of the optimum heat treatment in order to obtain the necessary properties of the working parts.
In order to increase the resistance of aluminium alloys a complex heat treatment is usually perfo... more In order to increase the resistance of aluminium alloys a complex heat treatment is usually performed. Therefore, we must consider the reaction time between aluminium alloys and furnace atmosphera. These atmospheres contain oxygene and nytrogene. Aluminium is an active element, therefore the oxidation is a very fast one.From the experiments made, the oxidation kinetics of aluminum alloys proves to depend
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