• Title/Summary/Keyword: Thermal analysis

Search Result 9,774, Processing Time 0.083 seconds

Thermal Analysis of Ceramic Materials (세라믹스 재료의 열분석)

  • Cha, Jaemin;Liu, Liyu;Ryu, Bongki
    • Ceramist
    • /
    • v.22 no.4
    • /
    • pp.393-401
    • /
    • 2019
  • Thermal analysis means the analysis of a change in a property of a sample, which is related to an imposed temperature alteration. Measurements are usually made with increasing temperature, but isothermal measurements or measurements made with decreasing temperatures are also possible. In fact, any measuring technique can be made into a thermal analysis technique by adding thermal control. Simultaneous use of multiple techniques increases the power of thermal analysis, and modern instrumentation has permitted extensive growth of application. The basic theories of thermal analysis are well developed and some of them are explained in this paper.

ASSESSMENT OF THERMAL FATIGUE IN MIXING TEE BY FSI ANALYSIS

  • Jhung, Myung Jo
    • Nuclear Engineering and Technology
    • /
    • v.45 no.1
    • /
    • pp.99-106
    • /
    • 2013
  • Thermal fatigue is a significant long-term degradation mechanism in nuclear power plants. In particular, as operating plants become older and life time extension activities are initiated, operators and regulators need screening criteria to exclude risks of thermal fatigue and methods to determine significant fatigue relevance. In general, the common thermal fatigue issues are well understood and controlled by plant instrumentation at fatigue susceptible locations. However, incidents indicate that certain piping system Tee connections are susceptible to turbulent temperature mixing effects that cannot be adequately monitored by common thermocouple instrumentations. Therefore, in this study thermal fatigue evaluation of piping system Tee-connections is performed using the fluid-structure interaction (FSI) analysis. From the thermal hydraulic analysis, the temperature distributions are determined and their results are applied to the structural model of the piping system to determine the thermal stress. Using the rain-flow method the fatigue analysis is performed to generate fatigue usage factors. The procedure for improved load thermal fatigue assessment using FSI analysis shown in this study will supply valuable information for establishing a methodology on thermal fatigue.

THE ORBITAL THERMAL ANALYSIS OF HAUSAT-2 AND ITS THERMAL CONTROL SUBSYSTEM PRELIMINARY DESIGN (HAUSAT-2의 궤도 열해석과 열제어계의 예비설계)

  • Lee Mi-Hyeon;Kim Dong-Woon;Chang Young-Keun
    • Bulletin of the Korean Space Science Society
    • /
    • /
    • pp.129-132
    • /
    • 2005
  • This paper describes BAUSAT-2 orbital thermal analysis and preliminary design of thermal control subsystem. To design thermal control subsystem of HAUSAT-2, we have considered active & passive thermal control method based on basic theory and themal equilibrium equation. Using this result, suitable thermal control method and material have been selected. We have designed thermal control subsystem based on analysis of HAUSAT-2's thermal environments on sun synchronous orbit with altitude 650km, inclination $98^{\circ}$ and thermal distribution and range expectation of each HAUSAT-2's surface. Thermal analysis consists of system level, box level and board level analysis. We have completed system level and box level analysis. Till now, board level analysis of main heat dissipation board in progress. Thermal control subsystem has designed according to thermal analysis result. This design is to maintain all of the HAUSAT-2 components within the allowable temperature limits. In future, STM

  • PDF

Thermal and structural analysis of a cryogenic conduction cooling system for a HTS NMR magnet

  • In, Sehwan;Hong, Yong-Ju;Yeom, Hankil;Ko, Junseok;Kim, Hyobong;Park, Seong-Je
    • Progress in Superconductivity and Cryogenics
    • /
    • v.18 no.1
    • /
    • pp.59-63
    • /
    • 2016
  • The superconducting NMR magnets have used cryogen such as liquid helium for their cooling. The conduction cooling method using cryocoolers, however, makes the cryogenic cooling system for NMR magnets more compact and user-friendly than the cryogen cooling method. This paper describes the thermal and structural analysis of a cryogenic conduction cooling system for a 400 MHz HTS NMR magnet, focusing on the magnet assembly. The highly thermo-conductive cooling plates between HTS double pancake coils are used to transfer the heat generated in coils, namely Joule heating at lap splice joints, to thermal link blocks and finally the cryocooler. The conduction cooling structure of the HTS magnet assembly preliminarily designed is verified by thermal and structural analysis. The orthotropic thermal properties of the HTS coil, thermal contact resistance and radiation heat load are considered in the thermal analysis. The thermal analysis confirms the uniform temperature distribution for the present thermal design of the NMR magnet within 0.2 K. The mechanical stress and the displacement by the electromagnetic force and the thermal contraction are checked to verify structural stability. The structural analysis indicates that the mechanical stress on each component of the magnet is less than its material yield strength and the displacement is acceptable in comparison with the magnet dimension.

A STUDY ON THERMAL MODEL REDUCTION AND DYNAMIC RESPONSE (열해석 모델 간략화 및 동적특성에 관한 연구)

  • Jun, Hyoung Yoll;Kim, Jung-Hoon
    • Journal of computational fluids engineering
    • /
    • v.19 no.4
    • /
    • pp.37-44
    • /
    • 2014
  • A detailed satellite panel thermal model composed of more than thousands nodes can not be directly integrated into a spacecraft thermal model due to its node size and the limitation of commercial satellite thermal analysis programs. For the integration of the panel into the satellite thermal model, a reduced thermal model having proper accuracy is required. A thermal model reduction method was developed and validated by using a geostationary satellite panel. The temperature differences of main components between the detailed and the reduced thermal model were less than $1^{\circ}C$ in steady state analysis. Also, the dynamic responses of the detailed and the reduced thermal model show very similar trends. Thus, the developed reduction method can be applicable to actual satellite thermal design and analysis with resonable accuracy and convenience.

Thermal Stress Analysis for the Printed Circuit Board of Electronic Packages (전자장비 회로기판의 열응력해석)

  • Kwon Y. J.;Kim J. A.
    • Korean Journal of Computational Design and Engineering
    • /
    • v.9 no.4
    • /
    • pp.416-424
    • /
    • 2004
  • In this paper, the heat transfer analysis and thermal stress analysis of the PCB(Printed Circuit Board) equipped in electronic Packages are carried out for various may types of chips on the PCB. And two structural PCB models are used in the analyses. The electronic chips on the PCB usually emit heat and this heat generates the thermal stress around the chip. The thermal load due to the heat generation of chips on the PCB may cause the malfunction of the electronic packages such as a monitor. a computer etc. Hence, the PCB should be designed to withstand these thermal loads. In this paper, the heat transfer analysis and thermal stress analysis are executed for the PCB model with pins and the analysis results are compared with the results for the PCB model without pins. The analysis results show that the PCB model without pins is not good for the thermal stress analysis of PCB, even though these two models have similar heat transfer characteristics. The analysis results also show that the highest thermal stress occurs in the pin especially attached to the highest temperature chip, and the PCB constrained to the electronic package on the long side is structurally more stable than other cases. The analyses of the PCB are executed using the finite element analysis code, NISA.

Thermal Analysis of IPMSM with Water Cooling Jacket for Railway Vehicles

  • Park, Chan-Bae
    • Journal of Electrical Engineering and Technology
    • /
    • v.9 no.3
    • /
    • pp.882-887
    • /
    • 2014
  • In this paper, the water cooling method among the forced coolant cooling methods is considered to be applied to the 110kW-class IPMSM for railway vehicles. First, basic thermal property analysis of the IPMSM is conducted using the three-dimensional thermal equivalent network method. Then, based on the results of the basic thermal property analysis, some design requirements for the water cooling jacket are deduced and a basic design of the water cooling jacket is carried out. Finally, thermal equivalent circuit of the water cooling jacket is attached to the IPMSM's 3D thermal equivalent network and then, the basic thermal and effectiveness analysis are conducted for the case of applying the water cooling jacket to the IPMSM. In the future, the thermal variation trends inside the IPMSM by the application of the water cooling jacket is expected to be quickly and easily predicted even at the design step of the railway traction motor.

A study on the flow and thermal analysis of the hot gas casing of gas turbine (가스 터빈 Hot gas casing에 대한 유동 및 열응력 해석)

  • Choi, Young-Jin;Lee, Young-Shin;Kim, Jae-Hun;Park, Won-Seek;Kim, Hyun-Soo
    • Proceedings of the KSME Conference
    • /
    • /
    • pp.557-561
    • /
    • 2004
  • The hot gas casing of gas turbine has operated high temperature and thermal gradient. The structure safety of hot gas casing will be highly depend on the thermal stress. In this paper, flow and thermal stress analysis of hot gas casing is carried out using ANSYS program. The obtained temperature data by flow analysis of hot gas casing apply the load condition of the thermal analysis. The thermal stress analysis is carry out the elastic-plasticity analysis. The pressure, temperature and velocity of the flow and thermal stress of the hot gas casing are presented.

  • PDF

Thermal Stress Analysis for a Brake Disk considering Pressure Distribution at a Frictional Surface (마찰면의 압력 분포를 고려한 제동디스크의 열응력 해석)

  • Lee Y.M.;Park J.S.;Seok C.S.;Lee C.W.;Kim J.H.
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • /
    • pp.842-846
    • /
    • 2005
  • A brake disk and a pad are important parts that affect the braking stability of a railway vehicle. Especially, because a brake disk stops the vehicle using conversion of the kinetic energy to frictional energy, thermal fatigue cracks are generated by the cyclic thermal load, as frictional heat, on a frictional surface and these cracks cause the fracture of a brake disk. Therefore, many researches for the thermal stress must be performed to improve the efficiency of brake disk and ensure the braking stability. In this study, we performed the thermal stress analysis for a ventilated brake disk with 3-D analysis model. For that, we simplified the shape of a ventilated hole to minimize problems that could be occurred in analysis process. Thermal stress analysis was performed in case that pressure distributions on a frictional surface is constant and is not. To determine pressure distributions of irregular case, pressure distribution analysis for a frictional surface was carried out. Finally using the results that were obtained through pressure distribution analysis, we carried out thermal stress analysis of each case and investigated the results of thermal stress analysis.

  • PDF

Development and Verification of Thermal Analysis Model for Thermal Vacuum Test of Satellite Components (인공위성 탑재품 수준 열진공 시험에 대한 열해석 모델의 개발과 환경시험 결과를 이용한 검증)

  • Kim, Sang-Ho;Seo, Hyun-Suk;You, Jae-Ho;Han, Eun-Soo;Kim, Tai-Kyung;Kim, Hyeong-Dong;Huh, Hwan-Il
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.38 no.8
    • /
    • pp.842-847
    • /
    • 2010
  • Thermal analysis for the simulation of satellite component level thermal vacuum test processes was carried out by considering thermal vacuum test environment condition, thermal vacuum chamber configuration, and satellite's inner thermal environment. The transient analysis results can be obtained for the temperatures of component and thermal vacuum chamber assemblies. The thermal analysis model was verified with the component thermal environmental test results by using enhanced thermal vacuum chamber.