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Mapping of Flow Visualization and Heat Transfer Analysis Over Roughened Plate Inside Rectangular Duct

  • Anup Kumar
  • Apurba Layek
Conference paper
Part of the Advances in Intelligent Systems and Computing book series (AISC, volume 755)

Abstract

In recent decades, liquid crystals thermography (LCT) technique which is optical and inexpensive technique for visualizing surface temperatures distribution and measuring heat transfer coefficients. The optical technique is build with the help of thermo-chromic liquid crystals enforced to the test surface. The main objective of this study is to visualize temperature fields through image processing for certain set of working parameters and to study of heat transfer characteristics with turbulators mounted over flat plate in a rectangular channel. The working geometric parameter for the roughened rectangular air duct are angle of attack of fluid flow (α) with the range of 30°–90°, relative pitch ratio (P/e) with range of 7–9, relative twist ratio (Y/e) with of range 3–5 and Reynolds number (Re) with the range of 14000–21000. Predictions of Nusselt number with roughened surface is compared with the smooth duct with same condition.

Keywords

Solar air heater Heat transfer Liquid crystal thermography Image processing 

Nomenclature

L

Length of the duct, m

W

Width of the duct, m

D

Depth of the duct, m

P/e

Relative pitch ratio (dimensionless)

Y/e

Relative twist ratio (dimensionless)

α

Angle of attack (degrees)

H

Hue (dimensionless)

Tfm

Mean temperature of air (°C)

TLCT

Temperature of LCT sheet/absorber plate (°C)

Dh

Hydraulic diameter (m)

k

Thermal conductivity of air (W/m°C)

V

Wind velocity of air (m/sec)

υ

Kinematic viscosity (m2/s)

h

Convective heat transfer coefficient (W/m2°C)

Q

Convective heat flux (W)

Nu

Nusselt number (dimensionless)

Re

Reynolds number (dimensionless)

Notes

Acknowledgements

The authors gratefully acknowledge the financial support of the Science and Engineering Research Board (SERB), Department of Science and Technology (DST), Govt. of India for initiating this research activity in Mechanical Engineering Department at National Institute of Technology Durgapur, India—Reference SERB-DST Grant: SB/EMEQ-314/2013; dated: 08/07/2013.

References

  1. 1.
    Copper, T. E., Filed, R. J., Meyer, J. F.: Liquid crytal thermography and its application to the study of convective heat transfer, transactions of the ASME, pp 442–450 (1975)Google Scholar
  2. 2.
    Baughn, J.W.: Liquid crystal methods for studying turbulent heat transfer. Int. J. Heat Fluid Flow 16, 365–375 (1995)CrossRefGoogle Scholar
  3. 3.
    Lee, K.C., Yianneskis, M.: A liquid crystal thermo graphic technique for the measurement of mixing characteristics in stirred vessel. Trans. Icheme. 75(A), 746–754 (1997)CrossRefGoogle Scholar
  4. 4.
    Liou, T.M., Chen, C.C., Tsai, T.W.: Heat transfer and fluid flow in a square duct with 12 different shaped vortex generators. J. Heat Transf. 122, 327–335 (2000)CrossRefGoogle Scholar
  5. 5.
    Kenning, D.B.R., Konno, T., Wienecke, M.: Investigation of boiling heat transfer by liquid crystal Thermography. Exp. Therm. Fluid Sci. 25, 219–229 (2001)CrossRefGoogle Scholar
  6. 6.
    Tanda, G.: Heat transfer and pressure drop in a rectangular channel with diamond shaped elements. Int. J. Heat Mass Transf. 44, 3529–3541 (2001)CrossRefGoogle Scholar
  7. 7.
    Gao, X., Sunden, B.: Heat transfer and pressure drop measurement in rib roughened rectangular ducts. Exp. Therm. Fluid Sci. 24, 25–34 (2001)CrossRefGoogle Scholar
  8. 8.
    Cavallero, D., Tanda, G.: An experimental investigation of forced convection heat transfer in channels with rib turbulators by means of liquid crystal thermography. Exp. Therm. Fluid Sci. 26, 115–121 (2002)CrossRefGoogle Scholar
  9. 9.
    Tariq, A., Swain, S.K., Panigrahi, P.K.: An experimental study of convective heat transfer from flat and ribbed surface. Indian J. Eng. Mater. Sci. 9, 464–471 (2002)Google Scholar
  10. 10.
    Malay K.D., Tariq, A., Panigrahi, P.K., Muralidhar, K.: Estimation of convective heat transfer coefficient from transient liquid crystal data using an inverse technique. Inverse Probl. Sci. Eng.1–23(2004)Google Scholar
  11. 11.
    ASHRAE Standards: Methods of testing to determine the thermal performance of solar collectors, pp. 93–77. New YorkGoogle Scholar
  12. 12.
    Stasieka, J., Stasieka, A., Jewartowskia, M., Collins, M.W.: Liquid crystal thermography and true-colour digital image processing. Opt. Laser Tech. 38, 243–256 (2006)CrossRefGoogle Scholar

Copyright information

© Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringNational Institute of Technology DurgapurDurgapurIndia

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