• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1995년도 추계학술대회 논문집
• /
• pp.371-374
• /
• 1995

The real-time holographic interferometer with a digital high-speed camera is applied to the visualization of transient temperature field. Collimated and diffused laser beams are used to the object beam according to the shape and transmittance of the phase object. Also, ESPI(Electronic Speckle Speckle Pattern Interferometer) technique is used to the visualization and quantitatie measurement of slow-varying temperature field. The experimental results obtained form these two techniques are discussed.

• 한국가시화정보학회지
• /
• 제22권1호
• /
• pp.79-84
• /
• 2024

As microchips' degree of integration is getting higher, its cooling problem becomes important more than ever. One of the promising methods is using fractal microchannel heat sink by mimicking nature's Murray networks. However, most of the related works have been progressed only by numerical analysis. Perhaps such lack of direct experimental studies is due to the technical difficulty of the temperature and heat flux measurement in complex geometric channels. Here, we demonstrate the direct visualization of in situ temperature profile in a fractal microchannel heat sink. By using the temperature-sensitive fluorescent dye and a transparent Polydimethylsiloxane window, we can map temperature profiles in silicon-based fractal heat sinks with various fractal scale factors (a=1.5-3.5). Then, heat transfer rates and pressure drops under a fixed flow rate were estimated to optimize hydrodynamic and thermal characteristics. Through this experiment, we found out that the optimal factor is a=1.75, given that the differences in heat transfer among the devices are marginal when compared to the variances in pumping power. This work is expected to contribute to the development of high-performance, high-efficiency thermal management systems required in various industrial fields.

• 한국가시화정보학회지
• /
• 제20권3호
• /
• pp.58-66
• /
• 2022

The high heat emitted from the process module and heat jacket may cause errors in semiconductor process equipment. Barriers were designed to reduce the temperature of surface on transfer module. A designed barrier was compared and analyzed by numerical analysis using ANSYS Fluent. The average temperature of barrier and effect of radiation heat transfer were also compared through absorbed radiative heat flux of the barrier. The adoption of the barrier had an effect on the radiative heat transfer reduction of the transfer module rod. The effect of the angles of barrier from 50° to 90° on the heat transfer was investigated using the absorbed radiative heat flux with the average temperature. The angle of barrier of 50° reduced the temperature up to 9.6 %.

• 한국가시화정보학회지
• /
• 제13권3호
• /
• pp.24-28
• /
• 2015

The temperature of the wafer batch in the furnace was calculated and its visualized temperature field was analyzed. The main heat transfer mechanisms from the heater wall to the wafers were radiation and conduction, and the finite difference method was used to analyze the complex heat transfer including those two mechanisms. The visualized temperature field shows that the direction of the heat flux in the wafer batch varies during the heating process, and the heat in the wafer batch diffuses faster by conduction within the wafer than by radiation between the wafers, in the condition of the constant temperature at the heater wall and cap.

• 한국정보통신학회논문지
• /
• 제26권1호
• /
• pp.146-152
• /
• 2022

라즈베리 파이나 아두이노를 이용하여 온도, 습도, 기울기, 압력 센서 등에서 수집한 정보는 자동 항온, 항습 시스템 등에 활용되고 있다. 또 농축산업에 활용하여 원격에서 스마트폰만으로 시스템을 제어함으로써 농축산업 종사자들이 편리하게 활용하기도 한다. 일반적으로 온도, 습도는 꺾은선 그래프 등으로 표현하여 변화를 실시간으로 감시하는 역할을 수행하기도 한다. 온도를 시각적으로 표현하는 기술은 최근 코로나19의 발열 검사를 위해 적외선 기기를 이용해 직관적으로 활용되기도 한다. 본 논문에서는 라즈베리 파이와 DHT11 센서에서 수집된 정보를 직관적인 시각화를 통해 공간상의 온도변화를 예측하고 즉각적인 대응이 가능하도록 제안한다. 이를 위해 온도, 습도를 효과적으로 시각화하기 위해 알고리즘을 만들었고, 일부 센서에 결함이 발생하는 경우에도 데이터 표현이 가능하다.

• 한국가시화정보학회지
• /
• 제8권4호
• /
• pp.54-59
• /
• 2010

A laser moxibustion therapy device having effect similar to that of traditional moxibustion is being developed using 1064 nm infrared laser. The therapy device allows direct interaction of laser light with the tissue rendering temperature distribution both on the skin surface and deep under the skin. We made a device that could measure temperature of deep under the surface of agar gel tissue phantom using thermocouples. A thermal imaging camera was used to verify results from the temperature measurement device. We compared the characteristics of heat transfer inside the tissue phantom during moxibustion and laser irradiation. The temperature distribution measured by thermocouples was found to be similar to that of distribution given by thermal imaging camera.

• 한국가시화정보학회지
• /
• 제6권1호
• /
• pp.27-33
• /
• 2008

Air flow inside an automotive HVAC module has been investigated using a high-resolution PIV technique with varying the temperature operation mode. The PIV system consists of a 2-head Nd:YAG laser (125 mJ), a high-resolution CCD camera (2K$\times$2K), optics and a synchronizer. A real automotive HVAC module was used directly under real operating condition. Some casing parts of the HVAC module were replaced with transparent windows for capturing clear flow images with laser light sheet beam illumination. Time-averaged velocity fields were obtained for two different temperature control modes. Flow characteristics of the air-conditioned air flow inside the automotive HVAC system for the two temperature baffle conditions were evaluated.

• 대한기계학회논문집B
• /
• 제31권2호
• /
• pp.132-140
• /
• 2007

The temperature and soot of the visualized diesel engine's turbulent flow of the flame was measured qualitatively. In the combustion chamber, in order to judge the affect that the swirl current has on the current ratio two heads with different ratios were used. Using a high speed camera, the results were analyzed using flame visualization. In order to measure the temperature and soot of the turbulent flames like diesel flames, two color methods were used to acquire temperature and the soot of the flames according to the conditions through analyzing the two wavelengths of the flames. It was possible to measure the highest temperature of the non-swirl head visualized engine, which is approximately 2400K, and that swirl head engine managed up to 2100K. With respect to the visualized diesel engine soot, we got the grasp of the KL factor which bears the qualitative information of the soot. This study is dedicated to suggesting the possibility of measuring not only the temperature but also soot of the diffusion flame of the diesel engine turbulent flames.

• 한국가시화정보학회지
• /
• 제21권1호
• /
• pp.103-109
• /
• 2023

This research developed a measurement technique that can measure the oxygen temperature inside a high temperature furnace. Instead of measuring only changes in frequency components within a small range used in the existing variable laser absorption spectroscopy, laser spectroscopy technology was used to spread out wavelength of the light source passing through the gas Based on a total of 20,000 image data, research was conducted to predict the temperature of a high-temperature furnace using CNN with black and white images in the form of spectral bands by temperature of 25 to 800 degrees. The optimal model was found through Hyper parameter optimization, R2 score is 0.89, and the accuracy of the test data is 88.73%. Based on this research, it is expected that concentration measurement and air-fuel ratio control technology can be applied.

• 한국가시화정보학회지
• /
• 제15권1호
• /
• pp.25-31
• /
• 2017

This study aims to visualize the Marangoni flow inside a droplet placed on heated hydrophobic surface and to measure its internal velocity field. The experimental result shows that the internal velocity increases with the increase of the plate temperature. In addition, the temperature difference induces the initial flow and drives the Marangoni circulation inside the droplet as soon as the evaporation starts (i.e. the thermal Marangoni flow). The fluorescence particles in the droplet trace two large-scale counter-rotating vortex pairs yielding the downwards flow along the vertical central axis. These vortex pairs gradually become small and move towards the contact line as time goes by, and this Marangoni flow sustains only for a half of the total evaporation time.