• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.4
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• pp.173-179
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• 2013

Middle-sized $CO_2$ water heater having compressor power of 7.45 kW was designed, and its performances were experimentally tested. Besides, optimum design of the $CO_2$ water heater was conducted by cycle simulation. When ambient temperature of $7^{\circ}C$ and hot water outlet temperature of $80^{\circ}C$ the $CO_2$ water heater showed the COP of 3.2. As hot water temperature increased the COP is getting decreased due to significant increase of compressor power consumption compared to increasing rate of heating capacity. When ambient temperature increased from $-3^{\circ}C$ to $12^{\circ}C$ the COP increased by 30%. The optimum components design of a gas cooler, an internal heat exchanger, and an evaporator were conducted, and the experimental correlation between amount of EEV opening and ambient temperature, and hot water temperature was suggested.

• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.6
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• pp.618-625
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• 2005

This paper has achieved that an optimal design and experiments of heater and cathode of electron gun that serve to embody high current density in CRT display. For the high brightness, high resolution and larger size in CRT display, high current density of electron gun is indispensible. An Impregnation style cathode is used, and must heighten operating temperature of heater to get high current density for this, it is proportional hereupon and power dissipation increases. In this paper, to get low power cathode with high current density, There are produced and tested sample that differ lead type of heater, coating method, the pitch and number of winding of the first and second coiling in the heat emission area for the low power design of high current density cathode heater in this paper.

• Journal of the Korea Convergence Society
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• v.13 no.3
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• pp.191-196
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• 2022

Unlike an international combustion engine car, a battery-powered electric vehicle requires an additional heat source for its heating system. A high-voltage coolant heater has the advantages of high efficiency and a wide operating temperature range. In its development, the geometry design of the coolant flow path is essential. This paper presents the thermal flow simulations of a 7kW high-voltage heater with symmetric serpentine flow channels arranged parallelly. The heater performance was evaluated from the simulation results in terms of the pressure and temperature differences and the flow uniformity. The proposed design showed a greater flow resistance and similar heat exchanging capability than the existing parallel serpentine design. It has the advantage of a relatively wide low-temperature surface area, where the control circuit board susceptible to high temperatures can be located.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.253-256
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• 2006

Most heater being used in vehicles has been used to a cabin heating by being supplied from a heat loss of the engine coolant for heat source efficiency. Recently, the heat loss is reduced by high efficiency in the engine. It becomes to require the combustion heater that directly bums the heater used in vehicles to provide heat source of the heater. The purpose of this study is to research a burner which will applicate combustion heater by the numerical analysis. There are the 5 different types of burners, which is designed by differently each design of the swirler. N-DODECANE by used the burner fuel is performed by numerical analysis in every 5 burner. The burner's efficiency testing is evaluated on the basis of the Exhaust gas temperature.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5541-5549
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• 2015

This paper introduces a safer and more power efficient heater by using induction heating, to apply to the semiconductor wafer fabrication exhaust gas cleaning system. The exhaust gas cleaning system is currently made with filament heater that generates an endothermic reaction of N2 gas for the removal of moisture. Induction theory, through the bases of theoretical optimization and electronic implementation, is applied in the design of the induction heater specifically for the semiconductor wafer exhaust system. The new induction heating design provides a solution to the issues with the current energy inefficient, unreliable, and unsafe design. A robust and calibrated design of the induction heater is used to optimize the energy consumption. Optimization is based on the calibrated ZVS induction circuit design specified by the resonant frequency of the exhaust pipe. The fail-safe energy limiter embedded in the system uses a voltage regulator through the feedback of the MOSFET control, which allows the system performance to operate within the specification of the N2 Heater unit. A specification and performance comparison from current conventional filament heater is made with the calibrated induction heater design for numerical analysis and the proof of a better design.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.350-353
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• 1999

This Paper Presents the optimized design of micro-heaters using 501(Si-on-insulator) substrate and oxide-filled trench structure In order to justify a lumped model approximation and thermal boundary assumptions, two-dimensional FDM(finite difference among which conduction is the dominant heat dissipation path. Compared with no-trenchs on the SOI structure, the micro-heaters with trench structures has properties of low heater loss and good thermal isolation. The simulation results show that the heater loss decreases as the number. width and distance of trenchs increases.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.1
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• pp.111-118
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• 2022

The vehicle industry requires superior technology that can increase the efficiency of the battery of an electric vehicle. A coolant heater that can optimize the temperature of the battery is one of the most effective techniques for cold environments. However, the vibrations generated by this device can cause major complications, such as leakage and system errors. Therefore, the vibrations of the device must be suppressed to improve the stability. In this study, the fastening conditions of a coolant heater were analyzed using a computer simulation to investigate the natural frequencies and mode shapes which reflect the primary reasons for the largest vibrations under the given operating conditions. The results showed that six-bolted joints could considerably improve the stability of the fastening device

• Archives of design research
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• v.6 no.1
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• pp.47-72
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• 1993

Nowadays conmpetltlOn of developing new products is getting keen. We can notice that the role and importance of design are emphasized more than ever.The main cause of this tendency is that technical power is no more a factor which secures the superiority in products competition, as technology is gneneralized in the world. Therefore, design is recognized intensely as a competitive strategy to promote competitive power of products. It is an already known fact that the design for both rational function and charming form to satisfy consumer's desires is a short cut to success, when a company develops a new product to promote competitive power in market. The design which plays a leading role in the activity of developing more cnovenient, more economical and more aesthetic products is called 'Competitive Edge' or 'New Corporate Weapon'. Judging form each company's case of developing products, we can guess that it has its own plan and process of developing new products with defferdnl interest and effort. The strategy of developing products is considered as the most important factor that affects the very existence of rhe company. This thesis is composed of six chapters in all. In the firstchapter, I describe the purpose, method, and scope of study.The second chapter includes the image of form in oil fan heater market in nearby Japan and that of interior in our domestic home and shops, and the trend of word life cycle by analyzing circumstances. The third chapter focuses on consumer's attitude. In the fourth chapter, I compare and test current products of competitive companies including Samsung, Daewoo, Shinilwith those of Gold STar. The trend of products, technique, and design which resulted form this comparison is described. In the fifth chapter I explain the strategy, and process of design of oil fan heater in 1992. The last conclusive chapter presents the major point drawed form the case study, but not includes an estimation of products and the condition of market. In this thesis, I reconsider the general understanding of design and designing process and the value of design as a main factor in the strategy of management by investigating the development of products and the strategy of design, and the process of design.

• Journal of Korean Institute of Industrial Engineers
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• v.40 no.2
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• pp.223-232
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• 2014

Life-cycle assessment (LCA) is often employed to quantify the environmental impact of a product in a comprehensive manner. The aspects of performance and usability as well as that of eco-friendliness should be considered in an integrated manner for the market competitiveness of an eco-friendly product. The present study developed a product improvement plan for an eco-friendly electric heater by benchmarking two small-size electric heaters (companies 'H' and 'T') in terms of performance, usability, and eco-friendliness. The performance measurements such as temperature, humidity, wind speed, noise, and power consumption were collected while the two heaters were operated in a laboratory setting. Then, the usability evaluations such as aesthetics, operation satisfaction, performance satisfaction, and overall satisfaction were surveyed for the two heaters using a 5-point scale (1 for very unsatisfied and 5 for very satisfied). Lastly, the LCA analysis was conducted by following the six-step process of eco-friendly product design provided by KEITI. The analysis results of the two products being integrated with the aspects of product, service, and user, four design improvement directions such as eco-efficient, smart, modularized, and user-support were recommended for an eco-friendly electric heater. These proposed concepts would be useful to develop an eco-friendly electric heater design with a high level of market competitiveness.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.416-422
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• 2007

The application analysis of bubble pump on the domestic solar water heater system is presented. The system investigated in this study is a passive device, self pumping and self regulating. It was test to use the bubble pump on solar water heater system. The test experiment has been taken on the existed vacuum tube about the efficiency, working fluid temperature and pressure and circulated power. In order to check the working temperature and working pressure effectively, the bubble pump was test separated from the solar water heater. The equipment consists of the bubble pump, heater and heat exchanger. The main structure of bubble pump was design depend on the character of two phase flow. The complete system was instrumented to measure pressures, temperatures and their relationship with the solar radiation intensity. The theory analysis of design bubble pump has been given and the experiment result analysis has been included in the paper.