The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
I.m. Richardson - One of the best experts on this subject based on the ideXlab platform.
-
Heat Distribution in resistance upset butt welding
Journal of Materials Processing Technology, 2009Co-Authors: N. F H Kerstens, I.m. RichardsonAbstract:Resistance upset butt welding (RUW) has been employed for wheel rim manufacturing for many decades. Recently there has been a trend toward improved production methods and the use of high strength materials, accompanied by an increasing demand for knowledge about the RUW process. One of the phenomena observed during RUW is an uneven Heat Distribution and temperature profile during welding. This work examines potential causes for hot spot formation and compares experimental observations with predictions from a simple thermal model to illustrate aspects of importance for adequate process control and reduction of weld rejection rates.
-
Heat Distribution in resistance upset butt welding
Journal of Materials Processing Technology, 2009Co-Authors: N. F H Kerstens, I.m. RichardsonAbstract:Resistance upset butt welding (RUW) has been employed for wheel rim manufacturing for many decades. Recently there has been a trend toward improved production methods and the use of high strength materials, accompanied by an increasing demand for knowledge about the RUW process. One of the phenomena observed during RUW is an uneven Heat Distribution and temperature profile during welding. This work examines potential causes for hot spot formation and compares experimental observations with predictions from a simple thermal model to illustrate aspects of importance for adequate process control and reduction of weld rejection rates. © 2008 Elsevier B.V. All rights reserved.
N. F H Kerstens - One of the best experts on this subject based on the ideXlab platform.
-
Heat Distribution in resistance upset butt welding
Journal of Materials Processing Technology, 2009Co-Authors: N. F H Kerstens, I.m. RichardsonAbstract:Resistance upset butt welding (RUW) has been employed for wheel rim manufacturing for many decades. Recently there has been a trend toward improved production methods and the use of high strength materials, accompanied by an increasing demand for knowledge about the RUW process. One of the phenomena observed during RUW is an uneven Heat Distribution and temperature profile during welding. This work examines potential causes for hot spot formation and compares experimental observations with predictions from a simple thermal model to illustrate aspects of importance for adequate process control and reduction of weld rejection rates.
-
Heat Distribution in resistance upset butt welding
Journal of Materials Processing Technology, 2009Co-Authors: N. F H Kerstens, I.m. RichardsonAbstract:Resistance upset butt welding (RUW) has been employed for wheel rim manufacturing for many decades. Recently there has been a trend toward improved production methods and the use of high strength materials, accompanied by an increasing demand for knowledge about the RUW process. One of the phenomena observed during RUW is an uneven Heat Distribution and temperature profile during welding. This work examines potential causes for hot spot formation and compares experimental observations with predictions from a simple thermal model to illustrate aspects of importance for adequate process control and reduction of weld rejection rates. © 2008 Elsevier B.V. All rights reserved.
Naoki Uchida - One of the best experts on this subject based on the ideXlab platform.
-
Analysis and Control of Heat Distribution in a Zone-Control Induction Heating System
Ieej Transactions on Industry Applications, 2020Co-Authors: Pham Ngoc Ha, Hideaki Fujita, Naoki Uchida, Kazuhiro OzakiAbstract:This paper discusses Heat Distribution on a workpiece in a zone-control induction Heating (ZCIH) system. The system consists of two or more split working coils and multi inverter units, and adjust the coil currents to control the Heat or temperature Distribution on the workpiece. This paper theoretically reveals the relation between the coil currents and the Heat Distribution, and proposes a simple method to calculate the Heat Distribution using a three-dimensional resistance matrix. The validity of the developed theory is confirmed by performing both numerical computation based on the finite element method (FEM) and experiments using a 1.5-kW six-zone ZCIH laboratory setup.
-
estimating method of Heat Distribution using 3 d resistance matrix for zone control induction Heating systems
IEEE Transactions on Power Electronics, 2012Co-Authors: Ha Ngoc Pham, Hideaki Fujita, Kazuhiro Ozaki, Naoki UchidaAbstract:This paper focuses on the analysis and control of the Heat Distribution in zone-control induction Heating (ZCIH) systems, which consist of two or more split working coils and inverter units. This paper carries out theoretical analysis of the generated Heat in the workpiece and reveals a relationship between the coil currents and the Heat Distribution. As a result, it is determined that the Heat Distribution can be estimated by a simple calculation using a 3-D resistance matrix. The experimental results which use a six-zone ZCIH laboratory setup, verify the validity of the developed theory.
-
Heat Distribution control using current amplitude and phase angle in zone-control induction Heating systems
2012 IEEE Energy Conversion Congress and Exposition (ECCE), 2012Co-Authors: Ha Ngoc Pham, Hideaki Fujita, Naoki Uchida, Kazuhiro OzakiAbstract:This paper proposes a new control method to expand the controllable zone number in a zone-control induction Heating (ZCIH) system. The ZCIH system consists of multiple working coils and multiple inverters to control the amplitude and phase angle of each coil current to obtain uniformity in the temperature profile across a workpiece. The ZCIH system makes it possible to control the Heat Distribution, resulting in a fast Heating capability at high temperature conditions. This paper derives a relation between the coil currents and the Heat generated on each zone, when the phase angle between coil currents are controlled. Based on the analysis, a new control method is proposed to control the generated Heat across the workpiece by adjusting both amplitudes and phase angles of the coil currents. Experimental results clarified that the proposed method can control the Heat generated on five zones using only three working coils. As a result, N working coils are possible to control the Heat generated on 2N-1 zones, leading to a remarkable Heat Distribution improvement and/or a significant cost reduction in the ZCIH system.
-
Analysis and control of the Heat Distribution in a zone-control induction Heating system
The 2010 International Power Electronics Conference - ECCE ASIA -, 2010Co-Authors: Pham Ngoc Ha, Hideaki Fujita, Kazuhiro Ozaki, Naoki UchidaAbstract:This paper deals with analysis and control of the Heat Distribution in zone-control induction Heating (ZCIH) systems. A ZCIH system consists of two or more split working coils and inverter units, which enables to control the Heat and/or temperature Distribution on the workpiece by adjusting the current amplitude through each working coil. This paper carries out the theoretical analysis of the generated Heat in the workpiece, and reveals a relation between the coil currents and the Heat Distribution. As a results, it is also clarified that the Heat Distribution can be estimated by a simple calculation using a three-dimensional resistance matrix. The experimental results are shown to verify the validity of the developed theory by using a six-zone ZCIH laboratory setup.
Kazuhiro Ozaki - One of the best experts on this subject based on the ideXlab platform.
-
Analysis and Control of Heat Distribution in a Zone-Control Induction Heating System
Ieej Transactions on Industry Applications, 2020Co-Authors: Pham Ngoc Ha, Hideaki Fujita, Naoki Uchida, Kazuhiro OzakiAbstract:This paper discusses Heat Distribution on a workpiece in a zone-control induction Heating (ZCIH) system. The system consists of two or more split working coils and multi inverter units, and adjust the coil currents to control the Heat or temperature Distribution on the workpiece. This paper theoretically reveals the relation between the coil currents and the Heat Distribution, and proposes a simple method to calculate the Heat Distribution using a three-dimensional resistance matrix. The validity of the developed theory is confirmed by performing both numerical computation based on the finite element method (FEM) and experiments using a 1.5-kW six-zone ZCIH laboratory setup.
-
estimating method of Heat Distribution using 3 d resistance matrix for zone control induction Heating systems
IEEE Transactions on Power Electronics, 2012Co-Authors: Ha Ngoc Pham, Hideaki Fujita, Kazuhiro Ozaki, Naoki UchidaAbstract:This paper focuses on the analysis and control of the Heat Distribution in zone-control induction Heating (ZCIH) systems, which consist of two or more split working coils and inverter units. This paper carries out theoretical analysis of the generated Heat in the workpiece and reveals a relationship between the coil currents and the Heat Distribution. As a result, it is determined that the Heat Distribution can be estimated by a simple calculation using a 3-D resistance matrix. The experimental results which use a six-zone ZCIH laboratory setup, verify the validity of the developed theory.
-
Heat Distribution control using current amplitude and phase angle in zone-control induction Heating systems
2012 IEEE Energy Conversion Congress and Exposition (ECCE), 2012Co-Authors: Ha Ngoc Pham, Hideaki Fujita, Naoki Uchida, Kazuhiro OzakiAbstract:This paper proposes a new control method to expand the controllable zone number in a zone-control induction Heating (ZCIH) system. The ZCIH system consists of multiple working coils and multiple inverters to control the amplitude and phase angle of each coil current to obtain uniformity in the temperature profile across a workpiece. The ZCIH system makes it possible to control the Heat Distribution, resulting in a fast Heating capability at high temperature conditions. This paper derives a relation between the coil currents and the Heat generated on each zone, when the phase angle between coil currents are controlled. Based on the analysis, a new control method is proposed to control the generated Heat across the workpiece by adjusting both amplitudes and phase angles of the coil currents. Experimental results clarified that the proposed method can control the Heat generated on five zones using only three working coils. As a result, N working coils are possible to control the Heat generated on 2N-1 zones, leading to a remarkable Heat Distribution improvement and/or a significant cost reduction in the ZCIH system.
-
Analysis and control of the Heat Distribution in a zone-control induction Heating system
The 2010 International Power Electronics Conference - ECCE ASIA -, 2010Co-Authors: Pham Ngoc Ha, Hideaki Fujita, Kazuhiro Ozaki, Naoki UchidaAbstract:This paper deals with analysis and control of the Heat Distribution in zone-control induction Heating (ZCIH) systems. A ZCIH system consists of two or more split working coils and inverter units, which enables to control the Heat and/or temperature Distribution on the workpiece by adjusting the current amplitude through each working coil. This paper carries out the theoretical analysis of the generated Heat in the workpiece, and reveals a relation between the coil currents and the Heat Distribution. As a results, it is also clarified that the Heat Distribution can be estimated by a simple calculation using a three-dimensional resistance matrix. The experimental results are shown to verify the validity of the developed theory by using a six-zone ZCIH laboratory setup.
James V. Carnahan - One of the best experts on this subject based on the ideXlab platform.
-
COMPARISON OF FAILURE RATES IN CONDUITS FOR UNDERGROUND Heat Distribution
Journal of Transportation Engineering-asce, 1998Co-Authors: Charles Marsh, James V. CarnahanAbstract:A survey of existing underground Heat Distribution systems was conducted to compare the failure characteristics of steel conduits with fiberglass reinforced plastic conduits. Pressure testing was carried out in order to set an objective standard for performance. Plastic conduits were found to have a failure rate 4–5 times as high as steel conduits. The implications of this for a comparative life-cycle cost analysis are very serious.
-
Investigation of preapproved underground Heat Distribution systems. Final report
1996Co-Authors: Charles Marsh, Nocholas M. Demetroulis, James V. CarnahanAbstract:The Department of Defense maintains and operates approximately 6,000 mi of steam and hot water Heat Distribution system piping, mostly underground. Even a small decrease in Heat transmission efficiency could waste large amounts of energy, natural resources, and lead to increased greenhouse gas production. USACERL investigated and evaluated the physical condition and general performance of drainable-dryable Heat Distribution systems installed since 1981. Inspections covered 35 Heat Distribution systems at 15 locations. Manhole inspections were performed and air pressure tests were successfully conducted on 5.18 mi of conduits. Many systems were not installed in accordance with criteria. Drains and vents were generally found to be dry; however, water or evidence of water in the manholes was common. Using a stringent standard of no more than a 1.0 psi drop in pressure after 30 min, 59 percent of the steel conduits passed while only 7 percent of the fiberglass reinforced plastic (FRP) conduits passed. With a more lenient standard of no more than a 5.0 psi drop in pressure after 30 min, 73 percent of the steel conduits passed while only 24 percent of the FRP conduits passed. In the more lenient case, normalizing to length, the failure rate of FRP-cased conduitsmore » was 4.82 times that of steel conduits.« less
-
Investigation of Preapproved Underground Heat Distribution Systems.
1996Co-Authors: Charles Marsh, Nocholas M. Demetroulis, James V. CarnahanAbstract:Abstract : The Department of Defense maintains and operates approximately 6,000 mi of steam and hot water Heat Distribution system piping, mostly underground. Even a small decrease in Heat transmission efficiency could waste large amounts of energy, natural resources, and lead to increased greenhouse gas production. USACERL investigated and evaluated the physical condition and general performance of drainable-dryable Heat Distribution systems installed since 1981. Inspections covered 35 Heat Distribution systems at 15 locations. Manhole inspections were performed and air pressure tests were successfully conducted on 5.18 mi of conduits. Many systems were not installed in accordance with criteria. Drains and vents were generally found to be dry; however, water or evidence of water in the manholes was common. Using a stringent standard of no more than a 1.0 psi drop in pressure after 30 min, 59 percent of the steel conduits passed while only 7 percent of the fiberglass reinforced plastic (FRP) conduits passed. With a more lenient standard of no more than a 5.0 psi drop in pressure after 30 min, 73 percent of the steel conduits passed while only 24 percent of the FRP conduits passed. In the more lenient case, normalizing to length, the failure rate of FRP-cased conduits was 4.82 times that of steel conduits.
-
Effects of Leak Detection/Location on Underground Heat Distribution System (UHDS) Life Cycle Costs: A Probabilistic Model
1991Co-Authors: Kent A. Miller, James V. Carnahan, E. SeganAbstract:Abstract : Army maintenance costs for underground Heat Distribution systems (UHDSs) were $51.4 million in fiscal year 1989 (FY89). Leak location, an important UHDS maintenance element, is accomplished by using leak location techniques in various sequences, depending on the type of Heat Distribution system. This report presents a model to estimate the probable costs of leak detection in both direct buried (DB) prefabricated conduit and concrete shallow trench (ST) Heat Distribution systems, given the inherent uncertainty of available detection techniques. Techniques discussed include visual inspection, random search, bisection search, infrared thermography, tracer gas, and acoustic emission. The projected leak location/repair costs for each UHDS are calculated, and the effects of maintenance costs on operation costs as a result of these projections are discussed. Also discussed are the construction cost/maintenance cost trade-offs that occur when comparing DB and ST life cycle costs. Underground Heat Distribution system, life cycle costs.
-
LEAK LOCATION AND REPAIR COST FOR UNDERGROUND Heat Distribution SYSTEMS
Journal of Transportation Engineering-asce, 1991Co-Authors: James V. Carnahan, K. Miller, E. SeganAbstract:The expected cost of leak location and repair is estimated for shallow trench and directly buried underground Heat Distribution systems. Leaks in shallow trench systems can be found during a visual search using a bisection method to determine the sequence of slabs to be lifted, while directly buried systems generally require sensors and often extensive excavation. The cost advantage for shallow trench systems is estimated to be $4,863 per mile per year (expressed in year 1985 dollars) for the baseline scenario, taking into account observed (historical) differences in average failure rates. If directly buried systems could somehow be guaranteed to have the same failure rate as shallow trench systems, the cost advantage would become negligible. Several scenarios regarding sensor effectiveness were entertained, with the cost advantage changing by less than 20%. Differences in capital costs and operating costs reported in other studies are offered for purposes of comparison. Since operating costs due to Heat ...
