Overview

In recent years, our main focus has been to elucidate the role of non-Newtonian rheology on flow field in model configurations including the flow over a single cylinder of circular, elliptic and square cross-sections and for two cylinders in a tandem arrangement, over a solid or a fluid sphere, etc. In particular, extensive results have been obtained on the detailed kinematics of the flow in terms of stream line patterns and isotherm contours to delineate the dead zones and local hot/cold regions. This information is crucial to achieve uniform product quality especially during the thermal processing of temperature sensitive materials (such as food-stuffs). Reliable values of the gross transport parameters including drag coefficient and Nusselt number encompassing wide ranges of the Reynolds number, Prandtl number and non-Newtonian flow parameters are also needed while performing process design calculations.

Awards
  • Fellow, Indian National Science Academy, New Delhi.

  • Fellow, The Academy of Sciences.

  • Fellow, National Academy of Sciences (India).

  • Fellow, Indian National Academy of Engineering.

Selected Publications
  • N. Nirmalkar, R. P. Chhabra and R. J. Poole, “Numerical predictions of momentum and heat transfer characteristics from a heated sphere in yield stress fluids", Ind. Eng. Chem. Res., 52, 6848- (2013).

  • R. Shyam, C. Sasmal and R. P. Chhabra, “Natural convection heat transfer from two vertically aligned circular cylinders in power-law fluids", International Journal of Heat & Mass Transfer, 64, 1127-1152 (2013).

  • R. Shyam, M. Sairamu, N. Nirmalkar and R. P. Chhabra, “Free convection from a heated circular cylinder in confined power-law fluids", International Journal of Thermal Sciences, 74, 156-173 (2013).

  • S. Sivakumar, N. Nirmalkar and R. P. Chhabra, “Effect of orientation on mixed convection from a heated square bar in Newtonian and power-law fluids", Numerical Heat Transfer, Part A, in press (2013).

  • N. Nirmalkar, R. P. Chhabra and R. J. Poole, “BEffect of shear-thinning behaviour on heat transfer from a heated sphere in yield-stress fluids", Ind. Eng. Chem. Res., 52, 13490-13504 (2013).

  • A. K. Tiwari and R. P. Chhabra, “Effect of orientation on steady laminar free convection heat transfer in power-law fluids from a heated triangular cylinder", Numerical Heat Transfer, Part A, in press (2014).

  • S. A. Patel and R. P. Chhabra, “Steady flow of Bingham plastic fluids past an elliptical cylinder", J. Non-Newt. Fluid Mechanics, in press (2013).

  • V. S. Nalajala, N. Kishore and R. P. Chhabra, “Effect of contamination on the rise velocity of bubble swarms at moderate Reynolds numbers", Chem. Eng. Res. Des., in press (2013).