Thermal Video System Research Articles

결로 발생 확률 평가를 통한 현대 신한옥 단열성능 향상 방안 연구

Purpose: In order to supply modern new han-oks having excellent thermal performance, careful review in the process of initial architectural planning step is required. The purpose of this study is to verify design guidelines that can maintain and improve environmental performance though analysis of estimation of condensation probability affected by initial design planning Method: To achieve this goal, measurements were carried out 6 Han-oks situated in OJUK han-ok village which were demonstrated to Gang-neung by taking a infra-red thermography using thermal video system. All evaluation targets are new han-oks style which the same structure and materials are applied. Following are analysis items; the exposure or not of wooden members, the difference according to the space usage, layout of the stationary closet facing directly on the outdoor air or not, influence of distributed arrangement of space using water, planning around the house door facing directly on the outdoor air and so on. Result: It was analyzed that the probability of condensation in case of the exposure of wooden members is higher than that of non exposed installation. Also, it was analyzed that the house door space facing directly the outside air needs introduction of entrance concept space which can minimize the heat loss. In stationary closet planning, it is necessary to consider the position of closet and the range of heating. And, it is judged that a separation planning between the space using water and the unused area is necessary.

내표면 온도차 비율(TDRi) 분석을 통한 현대 신한옥 외벽 모서리 부위 단열성능 평가

Recently, many New Han-oks have been constructing in all over the country to popularize as a type of green house. But, achievement of thermal performance of external wall is still the very important issue to become popular. Purpose: The purpose of this study is to verify the thermal performance level of modern New Han-ok through Temperature Difference Ratio inside(TDRi) analysis at corners of the external wall in Han-ok. Method: To achieve this goal, measurements were carried out in 12 Han-oks(experimental mock-up(1), exhibition Han-ok(1), happy village Han-oks(10)) by taking a infra-red thermography using thermal video system. Following are analysis items about connection joint between wall and wood columns of external wall conditions; the part between external wall and external wall(2D), external wall and ceiling(or floor)(2D), 2 external walls and ceiling(or floor)(3D) and so on. Result: It was analyzed that the probability of condensation at most of connection joint appear high and TDRi of 3D corners is higher than that of 2D corners in general. It means that the development of construction techniques about connection joint between wood columns and external wall is still required. The results of this study may be used to improve the construction technology of new Han-ok and as a basis for the specifying the desired thermal comfort environment of dwelling.

Fluid flow and heat transfer characteristics of liquid cooling microchannels in LTCC multilayered packaging substrate

The fluid flow and heat transfer of liquid cooling microchannels embedded in low temperature co-fired ceramic (LTCC) multilayered electronic packaging substrate have been investigated. Four cooling systems were supplied for high power application of 100W LED lamp, including aluminum finned heat sink and LTCC substrates with parallel, serpentine and spiral microchannels. The pressure, flow rate, Reynolds number, fiction factor, Poiseuille number and Nusselt number were experimentally measured and theoretically analyzed. The heat transfer behaviors characterized by the drop of maximum working temperature and temperature distribution were measured by a thermal video system based on infrared thermometry. The microstructure and roughness of microchannel were studied by using Scanning Electron Microscope and Tribo Indenter. The measured flow rate of parallel microchannel under the same inlet pressure was much higher than those of serpentine and spiral microchannels. A linear dependence of Nusselt number on Reynolds number was observed and conformed to the convective heat transfer mechanism in microchannel. The parallel microchannel was found to have the best heat transfer performance and reduced the maximum working temperature to 99.52°C, much lower than those of other cooling systems. The temperature distribution of LED lamp was also significantly improved by the internal parallel liquid cooling microchannel in LTCC substrate.

Experimental study of bump void formation according to process conditions

Experimental studies of void formation were performed using a solder paste with a small particle size and a thin substrate with a small solder resist opening (SRO) size. Two kinds of Sn–Ag–Cu solder paste, screen printing mask opening (MO) size and pad finishes, and three kinds of SRO sizes were used as process variables. In this study, paste type and MO size had little influence on the formation of voids. In general, fewer voids were formed using the electroless nickel electroless palladium immersion gold (ENEPIG) pad finish than the organic solderability preservative (OSP) pad finish. However, the suitability of the pad finish was different depending on the type of paste. Void formation reduced with decreasing SRO. Both focused ion beam cross-sectioning and a thermal video system were used to ascertain the mechanism of void formation when using the paste with a small particle size, and the entrapment of flux was identified as the main cause for the formation of voids.

Experimental rapid surface heating by induction for micro‐injection molding of light‐guided plates

AbstractThis work experimentally investigates the use of induction‐heating to heat mold surfaces rapidly, and thus enhance the replication effect of the microstructure of light‐guided plates (LGP) in the injection molding process. This investigation employs a 2‐inch LGP injection mold as the experimental carrier, and compares the replication effect on the microstructure of induction heating with that of conventional oil‐heating. Temperature increases on the mold plate are examined using a thermal video system. The experimental results show that (1) the flat induction coil design promotes rapid surface heating. (2) Induction‐heating the mold surface to 110°C improves the replication rate of the height of the micro‐structure by up to 95%. (3) The LGP produced by induction heating has no significant residual stress. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Experimental investigation of infrared rapid surface heating for injection molding

AbstractA low cost and practical infrared rapid surface heating system for injection molding is designed and investigated. The system was designed to assemble on the mold and a control system was used to operate the motion of the lamp holder. Four infrared halogen lamps (1 kW each) were used as the radiative source to heat the surface of mold insert. The temperature increase is verified on the mold plate with a thermal video system. Two types of specular reflectors combined with different bulb configurations were applied to study the heating ability of radiation heating. A modified spiral flow mold was used to test the enhancing filling ability of the rapid surface heating system. Three resins, PP, PMMA and PC were molded in the spiral flow injection molding experiments. If spherical reflector and centralized lamp configuration are used, the temperature at the center of the mold surface is the highest. The temperature of mold center surface is raised from 83°C to 188°C with 15 s of infrared heating. Because the surface temperature of the mold insert is higher than the glass transition temperature of resins before filling, the flow distance of resins in the modified spiral flow mold will be increased. The location effect of the infrared surface heating system on a thin‐long cavity was studied to demonstrate the possibility of using smaller infrared heating area on a large mold surface. A microprobe cavity also demonstrated that with the assistance of infrared heating technology the formability of a microprobe can be greatly improved. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3704–3713, 2006

Temperature evolution during stereolithography building with a commercial epoxy resin

AbstractIn this study, the temperature evolution during stereolithography (SL) processing of a commercial epoxy resin is experimentally measured and numerically simulated. Experimental tests were performed in a SL equipment to evaluate the temperature increase during laser‐activated photopolymerization. Temperatures on the resin surface were measured with a thermal video system in both static and moving laser experiments. For the moving laser experiments, the effect of the energy dose was tested by using different velocities of the scanning laser. The experimental results were compared with numerical model prediction obtained by numerical solution of heat transfer equations coupled with an original mathematical model developed for cationic photopolymerization kinetics. The results obtained from numerical simulation were in good agreement with experimental data for the scan performed at the lower energy dose. The process model describes both the temperature increase and the evolution of chemical reaction, providing information about the penetration depth and the cured linewidth. POLYM. ENG. SCI. 46:493–502, 2006. © 2006 Society of Plastics Engineers

P3-5 Measurement of Temperature Distribution on the Surface of Acoustic Reactor by Use of Thermal Video System(Poster session 3)

P3-5 Measurement of Temperature Distribution on the Surface of Acoustic Reactor by Use of Thermal Video System(Poster session 3)

Quenching of combustion waves in heterogeneous reaction systems: Time-resolved thermal vision studies

Time-resolved (30 frames/s), high temperature (up to ∼2300 K) Thermal Video System (TVS) was utilized for detailed real-time investigations involving quenching of the combustion wave in Ni+Al and Ti+Si reaction powder systems. The investigated samples were pressed into wedge-shape cut of massive Cu block, and after reaction was initiated at its top wide end the combustion wave propagated downward to the apex of the wedge. As the reaction front traveled, specific heat losses increased and at some critical position, combustion extinguished. It was shown that while front velocity gradually decreases approaching extinction, maximum combustion temperature remains essentially constant. This feature was explained based on a micro-heterogeneous model of combustion in gasless sytems. Further, analysis of dynamic temperature maps confirmed that quenching is a powerful tool forthe investigation of reaction routes and microstructure evolution in rapid heterogeneous combustion waves.

Evaluation of Plastic Deformation by Thermography Method (1st Report, Effect of Surface Roughness on Thermal Images)

Infrared thermography (TVS) is a device for conducting thermal radiation pattern from an object into a visible image. We paid attention to heat generation by plastic deformation and discussed the possibility of applying this device to detecting local plastic deformation by thermal video system. In measuring surface temperature distribution by this device, the emissivity is a very important factor of measuring the surface temperature distribution and largely depend upon the surface roughness. In this study, the relation between the emissivity and surface roughness was examined and we discussed the thermal image processing technique of the thermal image obtained by TVS.

Estimation of orthotropic thermal conductivity of honeycomb material

AbstractAn experimental–computational hybrid system for measurement of thermal conductivity of orthotropic materials is developed. The system consists of two experimental parts and a finite element analysis part. First, the temperature distribution generated by uniform heating is measured with a thermal video system, and the thermal conductivity of Z direction is calculated. Second, the temperature distribution generated by small area heating is measured with the system. In the final step, thermal transfer analyses simulating the experiment support efficient data, and thermal conductivity of in‐plane directions is estimated by comparison between experimental and analytical temperature distributions. The orthotropic equivalent thermal conductivity of honeycomb materials obtained by this system agreed with the theoretical values. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(8): 617–625, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10063

703 部分的に紫外線を受ける観葉植物の葉温

The temperatures of the surfaces of intact Epipremunum Aureum and Ficus Elastica leaves partially subjected to different intensities of ultraviolet (UV-B) irradiation as a function of time were investigated using a thermal video system and compared with those for the cases of in the dark and plant-upbringing irradiation. The results showed that the variations in the leaf temperature for UV-B irradiation were different from those for cases of in the dark and plant-upbringing irradiation, and were depended on the kind of plant studied and UV-B radiant intensity, as well as those previously obtained for case of leaves of intact Epipremumum Aureum and Ficus Elastica wholly subjected to UV-B irradiation.

406 紫外線を部分的に受ける観葉植物(ポトス)の葉温と葉面分光反射率

The temperature and spectral reflectance of the surfaces of intact Epipremunum Aureum leaves partially subjected to different intensities of ultraviolet (UV-B) irradiation as a function of time were investigated using a thermal video system and a spectrometer, respectively and compared with those for the cases of plant-upbringing irradiation. The results showed that the variations in the temperature and spectral reflectance for UV-B irradiation were different from those for case of plant-upbringing irradiation, and were depended on UV-B radiation intensity. Therefore, the temperature and spectral reflectance of the leaf surface suggested the possibility of applications in the prediction of the level of UV-B radiation.

Thermal Deformation Analysis of Honeycomb Sandwich Construction by using Honeycomb Model.

A simple method for thermal deformation analysis of a honeycomb sandwich construction (HSC), which is used as wall plates of buildings and mirror plates for parabolic antennas, was given. Orthotropic equivalent material properties are given theoretically by calculations with a periodical unit cell of honeycomb core. The theoretical thermal conductivities of the honeycomb core agreed with the value given by an experimental and computational hybrid system with thermal video system. A honeycomb model which has the theoretical material properties doesn't reduce the precision but significantly reduces the time for pre and post processes, and analyses.

Estimation of Orthotropic Thermal Conductivity of Honeycomb Material.

An experimental-computational hybrid system for measurement of thermal conductivity of orthotropic materials is developed. The system consists of two experimental parts and a finite element analysis part. Firstly, a temperature distribution generated by an uniform heating is measured with a thermal video system, and a thermal conductivity of Z direction is calculated. Secondary, a temperature distribution generated by a small area heating is measured with the system. In the final step, thermal transfer analyses simulated the experiment support efficient data, and thermal conductivity of in-plane directions are estimated by comparing between experimental and analytical temperature distributions. The orthotropic equivalent thermal conductivity of honeycomb materials given by this system agreed with the theoretical values.

Wear maps of Si3N4 ceramic cutting tool

Wear maps of a Si3N4 ceramic cutting tool for cutting 1045 plain carbon and 302 stainless steels are produced in this paper. Through the systematic turning tests, the optimum cutting regions were determined on the wear maps of a two-dimensional diagram of cutting speed and feed rate. They are important for selecting the appropriate cutting parameters for a ceramic tool when cutting different workpieces. The wear morphologies and wear mechanisms for the different regions were investigated by scanning electron microscopy (SEM) with energy dispersive analysis of x-ray (EDX), and the corresponding cutting temperature distributions were measured by a thermal video system. Based on the experiment results, the relationships between cutting conditions, cutting temperatures, and wear mechanisms were discussed in detail.

The computer simulation of the temperature distribution on the surface of ceramic cutting tools

The temperature distributions on the surface of Si 3N 4 and Ti(CN) ceramic cutting tools for turning different metallic materials were calculated and plotted using computer simulation based on a mathematic model of heat sources. The results showed that the temperature on the rake face of the ceramic cutting tools for turning 18-8 stainless steel was much higher than that for turning 1045 plain carbon steel due to the much lower thermal conductivity of the former, the temperature increased with increasing cutting speed. This observation is important in explaining the wear resistance and wear mechanisms of the two ceramic cutting tools. The computed temperature distributions on the surface of the ceramic cutting tools were checked by measurement with a thermal video system (TVS), and showed good agreement.

Infrared thermography and its application in the NDT of sandwich structures

Thermographic nondestructive testing (NDT) based on the thermal resistance effect of defects is developed for the inspection of delaminated and sandwiched defects embedded in composite structures. The resolution is examined for artificial delaminated defects in carbon-fiber honeycomb structures using conventional infrared radiation heating. The experimental results have demonstrated that radiation heating is effective for revealing defects in the composite structures. An experimental and computational hybrid system is developed for detecting defects in various composite structures. The system consists of an infrared thermal video system which measures the surface temperature distribution of the structure, a computer with a PIP-1024B image board which performs image processing of thermograms, and a HP ink jet XL printer. It is found that this system is readily applicable to the detection of defects located at the interface of the core and skin in honeycomb structures and delaminations in composite materials.

Evaluation of Deformation in Elasto/viscoplastic Body with Crack.

Some materials used to fabricate machines and structures have a strain rate dependence in their stress-strain characteristics at room temperature. In such materials, the deformation and strength depend on the loading velocity. We propose a noncontact evaluation technique using infrared thermography of macroscopic plastic deformation. To detect the heat generated during plastic deformation, an infrared thermal video system (TVS-2100) was employed. The relationship between the plastic deformation and temperature rise of the specimen surface was determined by analytical simulation of elasto/viscoplastic FE analysis coupled with transient heat conduction analysis. The experimental and numerical results are in good agreement, and the effect of the loading rate and the applicability of this evaluation technique by infrared thermography was demonstrated.

Application of Infrared Thermography to Detection of Flaws in Honeycomb Sandwich Constructions

We have developed an experimental and computational hybrid system which can be applied to the detection of flaws in structural members. The system consists of an infrared thermal video system by which the temperature distribution of the body surface can be measured, and an engineering work station which carries out image processing of the thermograms