• Fire Science and Engineering
• /
• v.25 no.3
• /
• pp.63-71
• /
• 2011

In this study, it was evaluated the fire risk of an electric heater as representative seasonal appliances. Two type of electric heaters were used in experiments. When electric heaters were operated, temperature variation was measured around the heater. Internal structure was understood by Nondestructive inspection. It was evaluated the tire risk of electric heaters, when flammable materials were positioned ear a heater. It was also estimated the probability of a tire in case of malfunction of a safety tip-over witch. When a heater was operated in a normal condition, temperature was maintained under $80^{\circ}C$ around the heater. The possibility of a fire is very high, when a heater is covered with flammable materials or malfunction of safety parts (safety tip-over switch, anti-overheating devices).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.06a
• /
• pp.305-306
• /
• 2006

자동차의 난방 열원은 HVAC(Heating, Ventilating & Air Conditioning)에 내장되어 있는 히터코어 (Heater Core) 에서 공급하게 되며, 이 히터코어는 엔진에서 가열된 냉각수 열원을 이용하게 된다. 그러나 최근 디젤 엔진의 경우 연소효율의 개선과 CEGR(Cooled Exhaust Gas Recirculation) 시스템의 적용으로 냉각부하가 증가하여 냉각수가 가지는 가용 열원이 기종보다 약 30~40% 정도 저하되고 있다. 따라서 디젤 자동차 및 하이브리드용 자동차의 난방 보조 히터의 국산화 개발이 시급해진 상황이며 초정밀, 고효율 보조 히터의 개발이 요구되고 있다. 현재 적용되고 있는 보조 히터 중에서 PTC 히터는 PTC 소자의 발열을 이용하여 공기를 직접 가열하기 때문에 추가적인 연료소비가 없고 소형 및 저가라는 장점이 있다. PTC 세라믹 소자는 $BaTiO_3$를 모체로 하며, 이의 특성 항상 및 제어를 위해서는 적절한 dopant를 선택하여 균일하게 doping 해야 한다. 지금까지 dopant에 따른 구성 요소 및 역할은 비교적 잘 알려져 있다. 하지만, 자동차용으로 사용되기 위해서는 12V의 저전압에서 동작해야 하며, 또한 소자의 두께가 얇아지게 됨에 따라서 발생하는 전기적 short와 같은 문제점들을 해결하여야 한다. 따라서 본 연구에서는 PTC 세라믹 소자에서 도펀트 종류와 양 조절을 통한 저저항을 확보하고, PTC 세라믹 소자의 박막화를 달성하고자 하였다.

• The Journal of the Korea Contents Association
• /
• v.18 no.10
• /
• pp.425-430
• /
• 2018

The battery system of an electric vehicle suffers from the problem the battery output and the service life decrease at low temperature. A Positive Temperature Coefficient(PTC) heater is used for maintaining room temperature but is heavy due to a complicated insulation structure. The larger the weight is, the lower the fuel economy of the electric vehicle is. On the other hand a induction heater have a simple insulation structure, which is effective in weight reduction and has a rapid temperature rise. The induction heater consists of an LC resonance circuit. The larger the capacitance is, the higher the price and weight is. Therefore, the inductance should be increased to reduce the capacitance. Also, the main heat source of the induction heater is coreloss. So, it is important to optimize inductance and coreloss in terms of electromagnetic field design. In this paper, the inductance and the coreloss according to the change of the induction heater structure were optimized through the Taguchi method and Finite Element Method(FEM) simulation.

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

• Journal of IKEEE
• /
• v.17 no.1
• /
• pp.63-70
• /
• 2013

In this paper, we have implemented the performance evaluation system of the unified fuel heater for CRDI diesel engine. If the diesel engine be cold by low temperature in winter, then that makes the waxing materials like a paraffin and is the source of poor engine starting. The unified fuel heater is the barrow meter that estimate the start performance of diesel engine, and be tested by test chamber. The chamber perform the normal temperature, an extremely low temperature, an operating performance in an extremely high temperature, the resistance operation delay time and current operation delay time in setting up test resistance, the bimetal delay time test in temperature variation, the current and resistor test of the composited heater, a heating operation test.

• Journal of IKEEE
• /
• v.18 no.1
• /
• pp.114-118
• /
• 2014

This paper presents improvement of the production process of a unified fuel heater with the help of the performance evaluation system. In order to enhance a starting capability of diesel-engine car, the unified fuel heater is proposed, which consists of main body, upper plate, stopper, lower plate, PTC, screw, bimetal and terminals. In the proposed heater, the sensor is combined with heater body not only to maximize the performance of car but also to reduce the production cost. The performance test chamber is proposed to evaluate the performance of heater. Especially, an effective manufacturing progress for assembling the heater elements can cut down expenses.

• Journal of Internet of Things and Convergence
• /
• v.7 no.3
• /
• pp.63-68
• /
• 2021

Domestic electric heater manufacturers are focusing on technology development to improve the efficiency of existing products. The electric heater for ship fuel is large in size and has high difficulty in miniaturization/high efficiency, so there are not many companies that try to develop technology yet. The existing electric heater has a structure of low heating efficiency because the contact time with the heat exchange tube of the heating medium is very short because the flow path of the ship engine fuel is monotonous. Since it is manufactured in a tubular shape, the volume is very large regardless of the heating efficiency. As a result, the tubular electric heater device applied by overseas advanced companies has difficulty in maintaining and repairing because it is necessary to decompose all tubular heaters when a specific part of the inside is damaged and if the heat exchange tube is damaged, all the heat exchange tubes must be decomposed. In this study, a basic study on plate type electric heaters capable of heating 10 tons of ship engine fuel per hour and setting a maximum temperature of up to 150℃ was conducted through a 250kW capacity plate type electric heater.

• Journal of the Korean Society for Railway
• /
• v.11 no.2
• /
• pp.151-157
• /
• 2008

The DPF temperature distribution which has a great effect on regenerating the ceramic filter effectively was measured at 30 locations using K-type thermocouples. Five partitioned electric heaters were used for heating the ceramic filter and they are switched ON/OFF in order. Also, the temperature distribution in the ceramic filter was measured with varying the electrical power supply to the heaters and the mass flow rate of the air supply from a blower. The uniform distribution of the air flow velocity at the inlet of the DPF make that of the temperature in the ceramic filter. The difference in heating ability between the partitioned heaters had a great effect on the temperature distribution in the ceramic filter.

• Proceedings of the KIEE Conference
• /
• 2008.07a
• /
• pp.1739-1740
• /
• 2008

수문관측용으로 사용되는 우설량계는 측정의 편의성과 강인성의 장점 때문에 대부분 전도형 우설량계를 사용하고 있으며, 하절기에는 강우량을 측정하고 동절기에는 강설량을 측정할 수 있도록 구성되어 있다. 동절기에 강설량을 측정하기 위하여 자동 히팅하는 장치가 포함되어 있어, 눈이 생성될 수 있는 온도조건에서 히터가 작동되고 적정온도가 되면 히터의 동작을 멈출 수 있도록 히터 및 온도센서가 구성되어 있다. 우설량계의 유지.관리 측면에서 주기적으로 동작상태 등을 점검하고 있으며, 히팅장치도 점검의 대상이다. 그러나 히팅장치의 동작 유무를 판단하는 방법에 있어서 효율적인 방법을 사용하고 있지 않고 있다. 따라서 본 연구에서는 평상시에 우설량계 점검시 온도센서에 의해 감지되는 가변적인 온도신호에 따라 히터가 제대로 작동되는지의 여부를 판단하기 위하여, 사전에 점검하기 용이하도록 우설량계 히터 동작시험 장치를 개발하였으며, 이 장치에 대한 동작특성을 분석하고자 한다.

• Journal of IKEEE
• /
• v.23 no.4
• /
• pp.1230-1235
• /
• 2019

In this paper, we have developed sensor composited heater of 2-pin, and unified the fuel filter. In order to evaluate the performance of the 2-pin sensor composited fuel heater, we have make of the low temperature fluidity system. The one measure and analysis the electrical and oil flow quantity characteristics at an input and out port of 2-pin sensor composited fuel heater. Especially, in the characteristics verification elements of the proposed goods, we use the test chamber for the temperature variable and oil flow quantity test, and designed an embedded system for interfacing an engine. By interfacing both user and the system, it support an experimental and date gathering function in 2-pin sensor composited fuel filter. And then test the temperature, oil pressure, electrical characteristics and oil flow quantity in variable status from - 30 ℃ to + 80 ℃. These can help us to determine the quality and performance of elementary goods.