KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Settings

Author: search.filters.author.Kaewkohkiat, Y.Subject: search.filters.subject.Turbulence flow

Search Results

Now showing 1 - 2 of 2
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Heat transfer enhancement in a channel with rib-groove turbulators
    (2010-04-01)
    Kaewkohkiat, Y.
    ;
    Kongkaitpaiboon, V.
    ;
    Eiamsa-Ard, S.
    ;
    Pimsarn, M.
    This paper presents the effects of the rib-groove turbulators on the heat transfer and friction characteristics in a rectangular channel. The experiments encompass the Reynolds number range from 1800 to 10,000; pitch ratios (PR=P/e) 6.6-13.3 by using air as the working fluid. The obtained results demonstrate that heat transfer rate in term of Nusselt number (Nu) increases with the increase of Reynolds number, whereas friction factor (f) shows the opposite trend. Both Nusselt number and friction factor increase with decreasing pitch ratio. It is also observed that heat transfer rate and friction factor for the channels with rib-groove turbulators are higher than those for the smooth channel under similar test conditions. In addition, the correlations for heat transfer rate in term of Nusselt number (Nu) and friction factor (f) for channel with rib-groove turbulators are also presented. © 2010 American Institute of Physics.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Combustion of rice husk in a fluidized bed combustor with wavy-surfaced chambers
    (2009-01-01)
    Kaewkohkiat, Y.
    ;
    Eiamsa-Ard, S.
    ;
    Wongcharee, K.
    ;
    Thungsotanon, D.
    ;
    Promvonge, P.
    The paper deals with an experimental investigation on effects of percent excess airs (EA = 15%, 30%, 45%, 60%, and 75%) on axial/radial temperature distributions, gas emissions and combustion efficiency in a fluidized bed combustor (FBC) with wavy surfaces using rice husk as the fuels. The combustion chamber shape is cylindrical with 200 mm in diameter (D) and 2400 mm in height (H). The top part of the chamber is designed and constructed to be wavy surface walls. In constructing the wavy surface bed at the top chamber, five modules of converging-diverging nozzles are inserted into the bed at which each module has a throat diameter of 100 mm and height of 200 mm. In the experiments, the axial/radial temperature distributions inside the combustor are measured for each percent excess air used while the feeding rate of rice husk is kept constant at 95 kg/hr. From experimental results, the emissions of flue gases are found to be CO = 308 ppm and NO<inf>x</inf> = 298 ppm, at EA = 75%. At all percent excess airs (EA) the axial/radial temperature distributions in the chamber are nearly uniform.