• Title/Summary/Keyword: Fluid mechanics

Search Result 559, Processing Time 0.027 seconds

Unique Fluid Ensemble including Silicone Oil for the Application of Optical Liquid Lens

  • Bae, Jae-Young;Park, Sung-Soo;Kim, Jae-Hong;Park, Chin-Ho;Choi, Young-Chul;Jung, Ha-Yong
    • Bulletin of the Korean Chemical Society
    • /
    • v.29 no.4
    • /
    • pp.731-735
    • /
    • 2008

  • The fluid ensemble in the liquid lens, which is composed of electrolyte and silicone oil, is the key material system to vary the focal length processing of the electrochemical desorption. In order to characterize the capability of the liquid lens according to response time and optical range, we prepared a fluid ensemble comprising the electrolyte and oil. To elucidate the physical mechanism of the effective response time, we examined the viscosity dependency while satisfying the requirements for the density and refractive index of the electrolyte and oil, respectively. The characterization results indicated that the response time (up and down) is influenced by the viscosity of the electrolyte and oil. On this basis, we prepared a fluid ensemble capable of reversibly adjusting for the focal length of the liquid lens, as well as the response time. The ensemble is applicable to various systems such as micro-lens and optical sensors.

  • https://doi.org/10.5012/bkcs.2008.29.4.731 인용 PDF KSCI

Unsteady Simulations of the Flow in a Swirl Generator, Using OpenFOAM

  • Petit, Olivier;Bosioc, Alin I.;Nilsson, Hakan;Muntean, Sebastian;Susan-Resiga, Romeo F.
    • International Journal of Fluid Machinery and Systems
    • /
    • v.4 no.1
    • /
    • pp.199-208
    • /
    • 2011

  • This work presents numerical results, using OpenFOAM, of the flow in the swirl flow generator test rig developed at Politehnica University of Timisoara, Romania. The work shows results computed by solving the unsteady Reynolds Averaged Navier Stokes equations. The unsteady method couples the rotating and stationary parts using a sliding grid interface based on a GGI formulation. Turbulence is modeled using the standard k-${\varepsilon}$ model, and block structured wall function ICEM-Hexa meshes are used. The numerical results are validated against experimental LDV results, and against design velocity profiles. The investigation shows that OpenFOAM gives results that are comparable to the experimental and design profiles. The unsteady pressure fluctuations at four different positions in the draft tube is recorded. A Fourier analysis of the numerical results is compared whit that of the experimental values. The amplitude and frequency predicted by the numerical simulation are comparable to those given by the experimental results, though slightly over estimated.

  • https://doi.org/10.5293/IJFMS.2011.4.1.199 인용 PDF