• Title/Summary/Keyword: Mixture Characteristics

Search Result 2,940, Processing Time 0.031 seconds

Consolidation Characteristics of Clay and Pond Ash Soil Mixture (점토와 매립회 혼합토의 압밀특성)

  • Chae, Deok-Ho;Yune, Chan-Young;Kim, Kyoung-O;Cho, Wan-Jei
    • Journal of the Korean Geotechnical Society
    • /
    • v.27 no.10
    • /
    • pp.45-54
    • /
    • 2011
  • In this study, the consolidation characteristics are investigated on the artificial soil mixture of kaolinite, fine soils representing dredged soils and reclaimed coal ash from the ash ponds. A large sedimentation chamber was designed and manufactured to produce the artificial soil mixture with uniform stress history. In order to examine the consolidation characteristics in lateral and vertical directions, standard consolidation and Rowe Cell tests were performed. From the results of standard consolidation tests, the artificial soil mixture with coal ash showed lower compressibility and the larger consolidation coefficients enough to aid in early stabilization of the reclaimed sites compared with the kaolinite only. Also, in order to examine the consolidation characteristics when applying vertical drains, the drainage material was installed and tested in the Rowe Cell. The Rowe Cell test results show that the artificial soil mixture yields higher coefficient of consolidation. Thus, the application of artificial soil mixture on the reclaimed sites can shorten the consolidation time.

Effects of the Air-Jet Loom Characteristics on the Hand Properties of the Sensitive Mixture Fabrics (Air-jet 직기 특성이 감성 교직물의 촉감에 미치는 영향)

  • Kim, Seung-Jin
    • Textile Coloration and Finishing
    • /
    • v.20 no.6
    • /
    • pp.63-68
    • /
    • 2008
  • The hand of the sensitive mixture fabrics was analysed and discussed with measured mechanical properties of two kinds of woven fabrics according to the characteristics of air-jet loom. The 16 mechanical properties such as tensile, bending, shear, compression and surface were measured using KES-FB system and their differences of the mechanical properties between domestic and foreign looms were analysed with the deviation according to the position of the specimen. And also these mechanical properties according to the domestic and Japan air-jet looms were analysed and discussed with warp and weft insertion tensions during weaving. This research is aiming to make a data base of fabric mechanical properties and, these analysed data are given to weaver as a basic research data related to the effects of loom characteristics to the sensitive mixture fabrics required from weaving fields.

Characteristics of Self-excited Combustion Oscillation and Combustion Control by Forced Pulsating Mixture Supply

  • Yang, Young-Joon;Fumiteru Akamatsu;Masashi Katsuki;Lee, Chi-Woo
    • Journal of Mechanical Science and Technology
    • /
    • v.17 no.11
    • /
    • pp.1820-1831
    • /
    • 2003
  • Characteristics of self-excited combustion oscillation are experimentally studied using confined premixed flames stabilized by a rearward-facing step. A new idea to suppress combustion oscillation was applied to the flames. The characteristics of unsteady combustion were examined, which is driven by forced pulsating mixture supply that can modulate its amplitude and frequency. The self-excited combustion oscillation having weaker flow velocity fluctuation intensity than that of the forced pulsating supply can be suppressed by the method. The effects of the forced pulsation amplitude and frequency on controlling self-excited combustion oscillations were also investigated comparing with the steady mixture supply. The unsteady combustion used in this experiment plays an important role in controlling self-excited combustion oscillations, and it also exhibits desirable performances, from a practical point of view, such as high combustion load and reduced pollutant emissions of nitric oxide.

Lightning Impulse Breakdown Characteristics of SF6-based Mixture Gases (SF6계 혼합가스의 뇌임펄스 절연파괴특성)

  • Seo, Ho-Joon;Rhie, Dong-Hee
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.18 no.7
    • /
    • pp.675-681
    • /
    • 2005
  • $SF_6$ is widely used as gas insulation medium because of having excellent dielectric and arc-quenching properties. However the use of it is getting to be suppressed from the viewpoint of mitigating global warming. For the development of environmentally-benign electric power equipment and system, novel gases or mixture gases are strongly required as the substitute of $SF_6$ gas. In this study the authors constructed an experimental system to investigate insulation properties of the mixed gases composed of negative $gas(SF_6)$ and electron deceleration gases$(N_2\;and\;CO_2)$. Breakdown and prebreakdown characteristics of $SF_6/N_2/CO_2$ mixture gases were investigated using the above mentioned system for different rates and gas pressures.

Dielectric Characteristics of $SF_6/N_2$ Mixture Insulation Gas for HV GIL (초고압 GIL을 위한 $SF_6/N_2$ 혼합가스의 절연특성)

  • Chang, Yong-Moo;Kim, Chul-Ho;Kim, Jeong-Tae;Koo, Ja-Yoon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2010.06a
    • /
    • pp.49-49
    • /
    • 2010
  • In this paper, a full scaled gas discharge chamber was designed and fabricated for evaluating the dielectric performance of SF6/N2 mixture gases. And it describes work on AC and lightning impulse dielectric characteristics of SF6/N2 mixture insulation gas from experiments and full scale models.

  • PDF

Effect of Ignition Energy Characteristics on the Ignition and the Combustion of a Premixed Gas(2) (점화에너지 특성이 예혼합기의 착화와 연소에 미치는 영향(2))

  • 이중순;강병무;김현수;정성식;하종률
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.5 no.6
    • /
    • pp.183-191
    • /
    • 1997
  • For the improvement of ignitability we need ignition energy and its discharge characteristics which are suitable for a part distribution of the mixture density around the ignition spark plug and the flow characteristics of the mixture in the combustion. Especially, for the solving of the instability of initial ignition and lean ignitability limit in the case of lean-burn combustion, the more powerful ignition energy is required. The conclusions from the observation can be summarized as follows: 1) The ignitability limit for HIS expands wider and the combustion is more stable than for CDI. 2) The combustion duration and ignition timing depend upon the distribution of local mixture density in the vicinity of ignition spark plug.

  • PDF

A Study on Mixture Composition and Combustion Characteristics in Gasoline Engine (가솔린 기관의 혼합기 조성과 연소 특성에 관한 연구)

  • Kim, Gi-Bok;Yoon, Chang-Sik
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.18 no.4
    • /
    • pp.197-206
    • /
    • 2015
  • Recently the automobile engine has been developed in achieving the high performance, fuel economy, and emission reduction. In a conventional spark ignition engine the fuel and air are mixed together in the intake system, inducted through the intake valve into the cylinder, and then compressed. Under normal operating conditions, the combustion is initiated towards the end of the compression stroke at the spark plug by an electric discharge. Following inflammation, a flame develops and propagates through this premixed fuel-air mixture. Therefore the state of mixture is very important in the combustion and emission characteristics. In this study the combustion and emission characteristics were tested and analyzed with changing the mixture composition and engine operating parameters in order to improve the combustion and performance in engine.

Influence of ion mobilities on discharge characteristics of AC-PDPs

  • Lee, In-Sook;Choi, K.Y.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2004.08a
    • /
    • pp.491-494
    • /
    • 2004
  • With recent experiments to add He atoms to the Ne-Xe discharge gas mixture for high luminous efficiency PDPs, we have performed simulations on a coplanar structured AC-PDP sustained in the three species He-Ne-Xe gas mixture. We found that the correct ion mobilities are essential to get the meaningful simulation results. We determined ion mobilities in the mixture gas and presented the calculated results regarding the influence of ion mobilities on discharge characteristics.

  • PDF

UV emission characteristics of Ne+$N_2$ gas-mixture discharges in AC Plasma Display Panel

  • Baek, Byung-Jong;Hong, Sang-Min;Choi, Kyung-Cheol
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2002.08a
    • /
    • pp.586-589
    • /
    • 2002
  • The Ultra Violet(UV) emission characteristics of Neon + Nitrogen gas-mixture discharge was investigated in AC plasma display panel. The firing voltage of Ne+$N_2$ gas-mixture discharge increased with increasing nitrogen concentration. The UV intensity emitted from the gas discharge also increased with increasing nitrogen concentration. The UV efficiency increase with increasing $N_2$ partial pressure at low $N_2$ concentration, and then UV efficiency is saturated at high $N_2$ concentration.

  • PDF

Effect of the Mixing Extraction of Perilla Seed and Peanut on Physicochemical Characteristics and Oxidative Stability of Perilla Oil (들께와 땅콩의 혼합 채유가 들기름의 이화학적 특성 및 산화안정성에 미치는 영향)

  • 권용주;김충기;오현화
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.28 no.6
    • /
    • pp.1212-1219
    • /
    • 1999
  • The oils were extracted from the mixture of roasted(for 20 min at 190oC) perilla seeds(RPS) and roasted (commercially) peanuts(RPN) by solvent extraction(SE) and mechanical expression(ME). The effects of mixing ratio on physicochemical characteristics and oxidative stability of their oils were investigated. Yields of both SE and ME oils were increased as the RPN ratio in the mixture increased. In all the SE and ME oils, the major fatty acids were oleic, linoleic and linolenic acid, and total saturated fatty acids increased gradually, but total unsaturated fatty acids decreased gradually as the RPN ratio in the mixture was increased. The specific gravity and refractive index of both SE and ME oils decreased as the RPN ratio in the mixture was increased. Acid value, saponification value and iodine value of SE oils decreased as the RPN ratio in the mixture increased, whereas acid value and iodine value of ME oils decreased and saponification value increased. The colors of ME oils were darker brownish than SE oils. The oxidative stability of SE oils was decreased as the RPN ratio in the mixture increased, whereas that of ME oils was increased. Sensory evaluation of all the oils extracted from the mixture with various mixing ratio showed significant differences in flavor, taste, color and overall acceptance(p<0.01). The oil extracted from the mixture of the mixing ratio of 8:2(RPS:RPN) showed slightly higher preference regardless of extraction method.

  • PDF