Shashikant Cholake
@bldeacet.ac.in
ASSISTANT PROFESSOR
BLDEA's Dr P G Halakatti college of Engineering and Technology
RESEARCH INTERESTS
Multi-mode heat transfer, Non-gray participating media, and radiation heat transfer, Stability analysis of fluids
FUTURE PROJECTS
Inverse methods in evaluating gas radiative properties
Gas radiative properties are highly non-linear and are functions of temperature, wave number, pressure, and mole fraction. Several forward models are available to calculate gas radiative properties, however, in some complex cases, it is required to use the inverse methodology to calculate the same.
Applications Invited
Faculties and research scholar working in radiation heat transfer
Scopus Publications
Scholar Citations
Scholar h-index
Scopus Publications
Shashikant Cholake, T Sundararajan, and S P Venkateshan
Springer Science and Business Media LLC
The onset of convection instability in a differentially heated layer consisting of gray and non-gray gaseous mixtures is studied numerically. The conditions investigated cover a wide range of Planck number values ( $$Pl = \\dfrac{\\kappa k_T}{4\\sigma T_0^3}$$ P l = κ k T 4 σ T 0 3 ), from the conduction-dominated regime of $$Pl\\gg 1$$ P l ≫ 1 to the radiation-dominated regime of $$Pl \\ll 1$$ P l ≪ 1 . The linear stability theory is applied to mass, momentum and energy balance equations and the resulting linear stability equations are solved by Chebyshev spectral collocation method. The divergence of radiative flux is solved by the finite-volume-based discrete ordinates method. The Spectral Line Weighted sum of gray gas (SLW) model is used to represent the fine spectral variation of absorption coefficient for a non-gray gas medium. The results indicate that the critical Rayleigh number ( $$Ra_c$$ R a c ) for the onset of convection increases with mean temperature ( $$T_0$$ T 0 ) in the conduction-dominated regime at low values of $$T_0$$ T 0 . In the radiation-dominated regime ( $$Pl\\ll 1$$ P l ≪ 1 ), $$Ra_c$$ R a c decreases with $$T_0$$ T 0 for gray media. If the medium is non-gray, the critical $$Ra_c$$ R a c reduces to even lower values (as compared with those of gray gases) due to the dependence of gas absorptivity on temperature $$T_0$$ T 0 . A reduction in the wall emissivity value increases the stability of the fluid layer due to reflection of radiation from the wall, in the radiation-dominated regime. The reverse trend is seen for $$Pl\\gg 1$$ P l ≫ 1 . The critical parameters also significantly depend on the concentrations of radiatively participating gases in the mixture. The temperature profile in the fluid layer transforms from a linear profile in conduction regime to a stratified profile with steep gradients near the walls, in the presence of non-gray participating gases.
Shashikant Cholake, Thirumalachari Sundararajan, and S. P. Venkateshan
Begellhouse
In the present work, the Rayleigh-Benard convective instability in a radiating fluid is studied numerically. The spectral collocation method based on Chebyshev polynomials is used to solve the linear stability equations while the Radiative Transfer Equation (RTE) is solved by the finite volume based discrete ordinates method. Weighted Sum of Gray Gases model (WSGG) has been used to incorporate non-gray behavior of the gas medium and solved along with RTE. The critical values of Rayleigh number and wave number are significantly influenced by the nongray behavior of the gas medium. Also, the mean operating temperature, mole fraction of gas species and wall emissivity play important roles with respect to the onset of fluid convection.
Shashikant Cholake, S. P. Venkateshan, and Thirumalachari Sundararajan
Begell House