Conference Papers

Permanent URI for this collectionhttps://idr.nitk.ac.in/handle/123456789/28506

Browse

Author: search.filters.author.Aruna, M.N.

Search Results

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    Investigating Sedimentation and Rheological properties of Magnetorheological Fluids using various carrier fluids
    (IOP Publishing Ltd, 2019) Aruna, M.N.; Rahman, M.R.; Joladarashi, S.; Kumara, H.
    The present paper focuses on the preparation of Magnetorheological (MR) fluids samples with three types of carrier fluids are silicone, light paraffin and Poly-alpha-olefin (5, 30 and 400 cSt) viscosity oils with 25% volume fraction of carbonyl iron particles and 3% fumed silica as a thixotropic agent to improve sedimentation of the MR fluid. The morphology, magnetic saturation and phase of the carbonyl iron particles were investigated using field emission scanning electron microscopy (FESEM), super quantum interface interference device (SQUID), X-ray diffraction (XRD) respectively. The results found that obtained powder particles spherical in shape, and a high magnetic saturation of 270 (emu/gm) with the applied field of 15000 (Oe). The prepared MR fluids rheological properties were tested using Anton Paar MCR702 Twin drive rheometer fitted with a magneto-rheological module. Sedimentation stability examined using direct observation method. © Published under licence by IOP Publishing Ltd.
  • No Thumbnail Available
    Item
    Investigation of steady state rheological properties and sedimentation of coated and pure carbonyl iron particles based magneto-rheological fluids
    (Elsevier Ltd, 2020) Swaroop, K.V.; Aruna, M.N.; Kumar, H.; Rahman, M.R.
    MR fluids face a major problem of sedimentation rate due to the high- density difference between the magnetic particles and the carrier medium that affects the performance of the magnetorheological devices. In this work, two MRF samples are prepared, where MRF-1 and MRF-2 are pure and coated carbonyl iron particles (CIPs) based MR fluids. The surface modification of the CIPs is performed using the solvent dispersion method to improve the sedimentation rate. The spherical shape and particle size analysis of the pure CIPs and coated CIPs' morphology is investigated using the Scanning Electron Microscope (SEM). The Thermal Gravimetric Analysis (TGA) shows that the coated CIPs have high thermal stability and confirm that 6% by wt. coating is present in the coated sample. The chemical bonding of the coated CIPs is detected using the Fourier Transform Infrared Spectroscopy (FT-IR). The saturation magnetization (Ms) of pure and coated CIPs is 245 emu/g and 120 emu/g, respectively, at 15 kOe, which is obtained by using a superconducting quantum interface device (SQUID). The rheology flow curve properties show that MRF-1 and MRF-2 exhibit yield stress of about 10 kpa and 9 kpa, respectively, for varying magnetic fields ranging from 0 to 343 kA/m. The Herschel-Bulkley model is fitted with the experimental data and the shear thinning behaviour is observed for both MR fluids. The sedimentation study shows that MRF-2 has better settling rate than MRF-1, which is observed by using the visual observation method up to 600 h. © 2020 Elsevier Ltd. All rights reserved.
  • No Thumbnail Available
    Item
    Rheological characterization of tragacanth gum coated carbonyl particles based magnetorheological fluid
    (American Institute of Physics Inc. subs@aip.org, 2020) Swaroop, K.V.; Aruna, M.N.; Kumar, H.; Rahman, M.R.
    The surface modification of soft carbonyl particle (CIPs) based magnetorheological (MR) fluids is the most popular method to solve sedimentation problem. In this present work,the two MR fluidswere prepared using pure CIPs (MRF#1) and Tragacanth gum coated CIPs (Tg/ CIPs) (MRF#2) are dispersed in hydraulic oil as a carrier fluid. The morphology, elemental composition and magnetic saturation properties were investigated using scanning electron microscopy (SEM),energy dispersive spectroscopy (EDS), superconducting quantum interface device (SQUID) analysis respectively. In addition to that,chemical bonding and thermal oxidation resistance of CIPs and (Tg/ CIPs) was analyzed using Fourier-transform infrared spectroscopy FTIR and thermo-gravimetric analyzer (TGA). The rheological properties of CIPs and Tg/CIPs based MRFs was tested to determine the flow behaviourat different currents 0,1,2,3 and 4Amps. The experimental results found that Tg/CIPs based MRFs is having higher yield stress of about (16kPa) than pure CIPs (15kPa). The decrease in the density of Tg/CIPs showed better sedimentation ratio (i.e r=91%) than the pure CIPs based MRFs which was observed using naked eye visual method. © 2020 Author(s).