• Title/Summary/Keyword: Thermal analysis characteristics

Search Result 2,348, Processing Time 0.033 seconds

Desorption characteristics of Activated Carbon and Activated Carbon Fiber by Development of Sorbent Tube for Measurement of Organic Solvent (유기용제 측정용 흡착관 개발을 위한 AC 및 ACF의 흡착특성)

  • 원정일;김기환;신창섭
    • Journal of environmental and Sanitary engineering
    • /
    • v.17 no.3
    • /
    • pp.99-109
    • /
    • 2002
  • Charcoal $tube/CS_2$ method are more popularly used than any other in the measurement of the working environment for the exposure evaluation of organic solvent, but it is some weak points that the lower accuracy can be obtained on the polar materials and within the range of the low concentration. Thus solvent desorption method has been developed to make accuracy higher and to overcome some weak points. However, because of high price of adsorption tube for thermal desorption and the short of study on its application to the working environment, it is not popularly used in the domestic industrial hygiene fields. This dissertation aims to develop thermal desorption and adsorption tubes for measuring organic solvents in the working environment, by comparing and analyzing breakthrough condition and adsorption capacity with ACF. Specific surface area of ACF used in this study is wider than the one of AC and micropore of ACF related with adsorption has been developed, and adsorption velocity and adsorption amount are very excellent by linking a pore of surface and an inside well into micropore. 1. Result of analysis on physical characteristics of adsorbent, the specific surface area of ACF was 1.3 times higher than that of AC. Distribution ratio of micropore related to adsorption was 94% on ACF and AC. Result of SEM, micropore of the AC is opened to the surface. In contrast, ACF shows that extremely fast adsorption speed. Because of micropore are exposed on the surface and penetrate through each other. 2. Breakthrough characteristics of adsorbents was not different from slop of breakthrough curve. The effluent concentration reaches 10% of initial concentration($C_{out}/C_{in}=0.1$, break point) of ACF was 30~316min longer than that of AC. Therefore, the adsorption capacities of ACF was 1.1~4.6 times higher than that of AC. ACF can be used as a proper adsorbent for measurement of organic solvent.

${\mu}$BGA and ${\mu}$Spring Packages for Rambus DRAM Applications and Their Electrical Characteristics (Rambus DRAM실장용 ${mu}!$BGA (Ball Grid Array) 및 ${mu}!$Spring 패키지와 전기적 특성)

  • Kim, Jin-Seong;Yu, Yeong-Gap
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.38 no.4
    • /
    • pp.243-250
    • /
    • 2001
  • This paper presents the structure of a $\mu$Spring package, its fabrication process and an analysis of its electrical characteristics compared to that of a $\mu$BGA. It was found that both $\mu$BGA and $\mu$Spring packages provide with outstanding high speed signal transmission characteristics due to their lower inductance of package interconnection lines, smaller than half of inductance of TSOP package lines. Even the worst case substrate trace of a Rambus DRAM $\mu$Spring package yields the line inductance of 2.9nH, which provides with 25% margin compared to the Rambus DRAM specification of 4nH. The fabrication cost of $\mu$Spring package is lower than that of $\mu$BGA by 50%, passes 1000 thermal cycles, meets JEDEC Level 1 specification whereas $\mu$BGA does not, and thereby yields high reliability and strong competing power.

  • PDF

Numerical Analysis on Cooling Characteristics of the Heat Sink for Amplifier (앰프용 히트싱크의 방열특성에 관한 해석적 연구)

  • Seo, Jae-Hyeong;Lee, Moo-Yeon
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.16 no.2
    • /
    • pp.947-951
    • /
    • 2015
  • The objective of this study is to numerically investigate the cooling characteristics of the heat sink as a cooling device for the amplifier. In order to analyze the heat transfer performances of the heat sink, the steady-state thermal model of the ANSYS software was used and analyzed with the fin thickness, fin pitch and fin number of the heat sink. As a result, the temperature at the junction of heat sink was decreased with the increase of fin thickness and fin number. In addition, the thermal resistances of the heat sinks were enhanced from $0.764^{\circ}C/W$ to $0.739^{\circ}C/W$ and $1.254^{\circ}C/W$ to $0.610^{\circ}C/W$, respectively, with the increase of the fin thickness from 1 mm to 3 mm and fin number from 9 to 20, respectively.

Synthesis and Characterization of Swallow-Tail Perylene Bisimide as Organic Phosphor for Hybrid LED (Hybrid LED용 유기 형광체로서의 Swallow-Tail Perylene Bisimide 제조 및 특성 연구)

  • Jung, Sung Bong;Jeong, Yeon Tae
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.32 no.1
    • /
    • pp.86-92
    • /
    • 2019
  • Although perylene bisimide derivatives have advantages such as excellent thermal stability and high luminance efficiency, they have poor solubility characteristics in organic solvents. In this research, in order to improve the solubility characteristics, we prepared perylene bisimide derivatives (1C) and (2C) with swallow-tail substituted imide, which is known to lead to excellent solubility. The structures and properties of swallow-tail perylene bisimide (1C) and (2C) were analyzed by $^1H-NMR$, FT-IR, UV/Vis spectroscopy, and thermogravimetric analysis (TGA). The maximum absorption wavelengths of (1C) and (2C) in the UV/Vis spectrum were 558 nm and 556 nm, respectively, and the maximum emission wavelengths were 602 nm and 600 nm, respectively. In the TGA, (1C) demonstrated good thermal stability with less than 5 wt% weight loss up to $242^{\circ}C$. In the solubility test, (1C) and (2C) exhibited solubilities of more than 5 wt% in chloroform, ethyl acetate, and dimethylformamide, but not in methanol. When the compounds (1C) and (2C) were mixed with PMMA (polymethyl methacrylate), thin films showed peaks at 679 nm and 677 nm, respectively, in the photoluminescence spectra. (1C) was found to be a possible candidate as red organic phosphor for hybrid LEDs.

A Study on the new MBT management system with variations of MSW's seasonal emission characteristics (생활폐기물의 계절별 성상변화에 따른 MBT 시스템 관리에 관한 연구)

  • Min, Byong-Hoon;Chung, Chan-Kyo;Kim, Jong-Moon;Min, Dul-le;Lim, Seung-Bin;Lee, Chae-Young;Kim, Hyung-Jin
    • Journal of the Korea Organic Resources Recycling Association
    • /
    • v.18 no.4
    • /
    • pp.54-63
    • /
    • 2010
  • When MBT(Mechanical Biological Treatment) facility is designed, the management system adequate for domestic circumstance in Korea has been insufficient and power plant's load on seasonal variation has not been resolved yet. Thus, this study introduced MBT facility and MSW(Municipal Solid Waste)'s seasonal emission characteristics were investigated in order to establish new MBT management system. and additional thermal buffer-materials's calorific values were also considered to reduce the power plant's load. The results showed that the screening efficiency of MBT facility and the physical characteristics of each waste can be identified, and the calorific value by seasonal variation for MBT facility can be kept constant all the year round by using an additional thermal buffer-materials.

Energy Storage Characteristics In Fixed Beds (Charging, Storing, Discharging)

  • Hassanein, Soubhi A.;Choi, Sang-Min
    • 한국연소학회:학술대회논문집
    • /
    • 2004.11a
    • /
    • pp.17-23
    • /
    • 2004
  • In the present work, the numerical model was refined to predict the thermal analysis of energy storage in a fixed beds during (charging ,storing, discharging) mode. The governing energy equations of both fluid and the solid particles along with their initial and boundary conditions are derived using a two-phase, one dimensional model. The refined model is carried out by taking into account change of (air density , air specific heat) with air temperature and also by taking into considerations heat losses from bed to surrounding. Finite difference method was used to obtain solution of two governing energy equations of both fluid and solid particles through a computer program especially constructed for this purpose. The temperature field for the air and the solid are obtained, also efficiency of energy stored inside the bed is computed. Finally using refined model the effect of air flow rate per unit area Ga (0.2, 0.3, and 0.4 kg/$m^2$-s), and inlet air temperature (200, 250, 300 $^{\circ}C$) on energy storage characteristics was studied in three mode ( charging ,storing, discharging). The rock particles of diameter 1 em is used as bed material in this research.

  • PDF

A Study on V-I Characteristics of Hydrogen-Oxygen Gas Generator

  • Yang Seung-Heun;Kang Byoung-Hee;Gho Jae-Soek;Mok Hyung-Soo;Choe Gyu-Ha
    • Proceedings of the KIPE Conference
    • /
    • 2001.10a
    • /
    • pp.109-112
    • /
    • 2001
  • Water-Electrolyzed gas is a mixed gas of the constant volume ratio 2:1 of Hydrogen and Oxygen gained from electrolyzed water, and it has better characteristics in the field of economy, efficiency of energy, and environmental intimacy than acetylene gas and LPG (Liquefied Petroleum Gas) used for existing gas welding equipment. So studies of Water-Electrolyzed gas are activity in progress nowaday, and commercially used as a source of thermal energy for gas welding in the industry. The object of this paper is getting a V-I characteristic of Hydrogen-Oxygen Gas Generator using DC source. First, chemical analysis of electrolysis is conducted and the relation of electrical energy and then chemical energy is investigated through the faraday's laws.

  • PDF

Synthesis and Characteristics of Porous Silica Ceramics with Organic Additives(I) (유기물 첨가에 따른 다공성 실리카 세라믹스의 제조 및 특성(I))

  • 신진용;이범재;노재성
    • Journal of the Korean Ceramic Society
    • /
    • v.35 no.9
    • /
    • pp.958-968
    • /
    • 1998
  • Porous silica ceramics were prepared using DCCA(Drying Control Chemical Additives) Such as uncharged polymer(Polyethylene glycol) and protein (Lipase) under H2O/Low-grade TEOS=10 C2H5OH/Low-grade TEOS=1 HC1/Low=grade TEOS=0.01 After Plain which doesn't added DCCA and samples of 11 sorts which varied molecular weight of PEG(Mw=600, 1000, 2000) quantity of Lipase and concentration of wat-er were synthesized gellation time and thermal analysis were investigated. After heat-treated at 600, cry-stal structures analyses of SiO2 polymer and characteristics of pores were investigated. Gellation time was retarded about 2-6 times as compared with plain resulting in addition of DCCA and crystal structures ex-hibited amorphous state. Moreover as increase of water a short gellation time was obtained. The samples added PEG showed increase of specific surface areas up to 20-40% and had micropores while those of Lipase were decreased about 90% and showed broad pore size distribution.

  • PDF

Analysis of Dynamic Performance of Solid Oxide Fuel Cells (고체산화물 연료전지의 동적 성능 특성 해석)

  • Yang, Jin-Sik;Sohn, Jeong-L.;Ro, Sung-Tack
    • Proceedings of the KSME Conference
    • /
    • 2004.11a
    • /
    • pp.1652-1657
    • /
    • 2004
  • Model for the dynamic simulation of dynamic behaviors of a solid oxide fuel cell (SOFC) is provided. This model is based upon (1) coupled mass and heat transfer characteristics and (2) important chemical reactions such as electrochemical and reforming reaction in high temperature fuel cells such as SOFC. It is found that the thermal inertia of solid materials in SOFC plays an important role to the dynamic behavior of cell temperature. Dynamic characteristics of cell voltage, power and chemical compositions with different levels of load changes are investigated.

  • PDF

A Study on Flow Characteristics in Muffler for 125cc Grade Motorcycle (125cc급 모터사이클용 머플러 내부 유동특성에 관한 연구)

  • Yi, Chung-Seob;Jeong, In-Guk;Yun, Ji-Hun;Suh, Jeong-Se
    • Journal of the Korean Society of Manufacturing Technology Engineers
    • /
    • v.21 no.2
    • /
    • pp.196-201
    • /
    • 2012
  • This study represents numerical study on the thermal and fluid flow characteristics of exhaust gas in a motorcycle muffler. The engine generates 125cc of displacement. Numerical analysis with computational fluid dynamics(CFD) was carried out to investigate the exhaust gas that flow into a motorcycle muffler. The STAR-CD S/W used to analyze three dimensional steady state and transient in a muffler. The Navier-Stokes Equation is solved with SAMPLE and PISO method in cartesian coordinates system. As the numerical result, it could be confirmed pulsating pressure generated from inlet of muffler become closer to the atmospheric pressure through baffle. Also the numerical result was almost identical to experimental result and, through the comparison, the reliability of numerical result was confirmed.