• 제목/요약/키워드: nonnewtonian fluid

검색결과 3건 처리시간 0.029초

Rheological Behavior of Glucosamine and Glucosamine Hydrochloride Suspensions under DC Electric Field

  • Kong, Sung-Wook;Kim, Seung-Wook;Choi, Ung-Su
    • KSTLE International Journal
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    • 제8권2호
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    • pp.35-37
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    • 2007
  • The electrorheological behavior of the glucosamine and glucosamine hydrochloride suspensions was investigated. The the glucosamine suspension behaved as a Newtonian fluid due to low conductivity even though it has polar group. The glucosamine hydrochloride suspension behaved as a Nonnewtonian fluid under the application of the electric field. The shear stress of the glucosamine hydrochloride suspension is proportional to 1.86 power of the electric field. The value of the structure factor, $A_s$ was 1 and it may be resulted due to the formation of single chain upon application of the electric field.

절단 원추형 전기점성 SFD 베어링 연구 (A Study on the Electroviscous(EV) Fluid Squeeze Film Damper(SFD) Bearing of the Truncated Cone Type)

  • 윤석철
    • 한국안전학회지
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    • 제18권3호
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    • pp.8-13
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    • 2003
  • Equivalent Reynolds equation of truncated cone type SFD bearing using nonnewtonian EV fluid is derived. The 3 nondimensional oil film pressures and its forces are obtained with axial and circumferential pressure gradient of bearing respectively, and dynamic characteristics for the stability of rotor-bearing system are obtaind through the governing equation for an elastic rotational shaft. It is shown that EV fluid is less sensitive to the changes of oil-film than newtonian fluids for dynamic characteristics. Therefore, results show that it is better to use an EV fluid with truncated cone type SFD bearing for the vibration control of rotational machines.