kankan pathak - Academia.edu (original) (raw)

Papers by kankan pathak

Journal of Thermal Science and Engineering Applications

An attempt has been made to investigate the performance of two methods of estimation of free and ... more An attempt has been made to investigate the performance of two methods of estimation of free and forced convection velocity components present in mixed convection. For this present analysis, a vertically configured shrouded plate finned channel is considered. From the literature, it is observed that in the solution of mixed convection problems related to the various engineering applications, proper estimation of induced velocity and fan/pump velocity plays a vital role. For this cause, segregation of the velocity components of free and forced convection present in the mixed convection becomes important. There exist two methods available in the literature, namely, first, the natural convection computational fluid dynamics method (NCM) used in the mixed convection computational fluid dynamics analysis under the same thermal and geometrical conditions, and second, forced convection decoupled method (FDM) applying the same pressure drop in forced and mixed convection across the channel....

2017 International Conference on Innovations in Information, Embedded and Communication Systems (ICIIECS), 2017

A computational study is made to investigate the effects of fin tip to shroud clearance on the th... more A computational study is made to investigate the effects of fin tip to shroud clearance on the thermal performance of a rectangular vertical shrouded fin array. Five sets of clearances are used in the present investigation. A fixed Grashof number (Gr) is used. Results indicate that dimensionless axial pressure achieves a lower value with the increase of fin tip to shroud clearance. For the selected inlet velocities bulk fluid temperature decreases with the increase of clearances. For smaller clearance local Nusselt number decreases sharply at the entrance region and achieves a local minimum value. Then it increases to a nearly constant value away from the inlet. Overall heat transfer coefficient first increases to a maximum value then it decreases with the increase of clearance. For narrower fin spacing maximum heat transfer coefficient is obtained at a non-dimensional clearance 0.10. Similar trend is obtained for larger fin spacing but maximum heat transfer occurs at a non-dimensio...

International Journal of Heat and Mass Transfer, 2020

Heat sinks/fins are widely used in rapid heat removal processes like cooling of electronic device... more Heat sinks/fins are widely used in rapid heat removal processes like cooling of electronic devices, car radiators, transformer coils, nuclear reactors, etc. The thermal efficiency of the heat sinks mainly depends on the conductivity of the material used. In the present work, a comparative study is made on the thermal performance of heat sinks having variable and constant heights with respect to the bulk temperature, induced velocity, fin height/spacing/clearance, fin thermal conductivity and efficiency. A computational code based on SIMPLER algorithm is developed to solve the present problem. Results indicate that the variation of local Nusselt number against the flow direction shows higher values for the nondimensional variable height heat sinks of 0.25 involving narrower fin spacing. It is also noted that consideration of finite conductivity of fin of 200 W/m-K and 75 W/m-K reduce the overall Nusselt number by 5.7% and 9.5% respectively while compared to an isothermal fin. Further, the use of variable height heat sinks coupled with a shorter fin height of 0.03 m indicates an improvement of thermal performance by around 225%.

International Journal of Thermal Sciences, 2019

Shrouded fin heat transfer has been investigated by many researchers in the recent time because o... more Shrouded fin heat transfer has been investigated by many researchers in the recent time because of its broad applicability in engineering/industrial applications. Literature unveils the fact that almost all studies involving shrouded fin consider the fixed-height fin array. There is a limited literature in which it is predicted that dualheight fin array augments the heat transfer. These results are important since they require lesser material for enhanced heat transfer. In this present study, a computational code is developed to study the mixed convective heat transfer from a shrouded vertical dual-height plate fin array for possible improved heat transfer. Results indicate that induced velocity increases with decreasing reduced-height of fin for smaller fin spacing which enhances the heat transfer rate. Variation of friction factor multiplied by the Reynolds number (fRe) with the geometric parameters shows lower value for the case of dual-height fin array. Overall heat transfer coefficient shows improved results for the dual-height fin array involving lower Grashof numbers at different inlet velocities. But, for higher velocities, better results are noticed only in the case of larger clearances. The thermohydrodynamic performance parameter is found to be greater for the dual-height fin array than that of the fixedheight fin array. Computed axial pressure difference and overall Nusselt number are correlated with the governing parameters of the problem.

Applied Mathematical Modelling, 2017

Comparison between exact thermal boundary condition and harmonic mean conductivity condition at t... more Comparison between exact thermal boundary condition and harmonic mean conductivity condition at the solid-fluid interface for finite thickness shrouded non-isothermal fin array,

Smart innovation, systems and technologies, Sep 1, 2022

Journal of Thermal Science and Engineering Applications, 2019

A numerical study is performed on simultaneous heat and mass transfer from a shrouded vertical no... more A numerical study is performed on simultaneous heat and mass transfer from a shrouded vertical nonisothermal variable height fin array, representing dehumidification process under natural convection. Fluid properties are treated as uniform, and the fluid is assigned to comply with Boussinesq approximation to include the effect of density variation with temperature and concentration. Semi-implicit method for the pressure linked equations revised (SIMPLER) algorithm is adopted to resolve pressure and velocity coupling. A detailed parametric investigation of fin spacing, variable fin height, and fin tip to shroud clearance for a range of thermal and mass Grashof number is undertaken. Results indicate that in case of smaller fin spacing, involving fin length of 0.3 m, coefficients of sensible and latent heat transfer increase with the decreasing variable height (H1*) of fin and become maximum at H1*=0.5, for all thermal and mass Grashof numbers considered presently. Further, total heat ...

International Journal of Heat and Mass Transfer, 2015