BITS Faculty Publications

Permanent URI for this communityhttp://localhost:4000/handle/123456789/1867

Browse

Filters

Settings

Author: search.filters.author.Sharma, Bhupendra KumarSubject: search.filters.subject.Heat transfer

Search Results

Now showing 1 - 10 of 13
  • No Thumbnail Available
    Item
    Entropy generation and heat transfer in nonlinear Buoyancy–driven Darcy–Forchheimer hybrid nanofluids with activation energy
    (De Gruyter, 2025-04) Sharma, Bhupendra Kumar; Yadav, Sangita
    This study investigates the influence of a magnetic field, activation energy, and heat source on the heat and mass transfer within a cross fluid embedded with mono-, di-, and tri-nanoparticles, considering thermal radiation and Darcy–Forchheimer effects. Utilizing the Cattaneo–Christov theory, non-Fourier heat transfer is modeled for a vertical moving surface. A mathematical model is developed and subsequently converted into a dimensionless form through an appropriate similarity transformation, resulting in a system of first-order ordinary differential equations. The numerical approach to solve the system is BVP4C solver in MATLAB, a tool specifically designed for boundary value problems. Graphical representations have been analyzed for velocity profiles, temperature profiles, and concentration distributions for different values of physical parameters. It is observed that the velocity profiles exhibit an upward trend with an increase in the parameters associated with nonlinear thermal convection and nonlinear concentration convection. Additionally, the analysis of surface shear stress, heat transfer coefficients, and mass transfer coefficients revealed that an increase in the porosity parameter and Forchheimer number results in decreased shear stress. Entropy generation is also investigated to quantify irreversibilities in the system. The analysis showed that increasing the Brinkman number, diffusion parameter, and temperature and concentration difference parameters leads to higher entropy generation, indicating greater irreversibility in the system. A comparative analysis demonstrates that tri-nanoparticles substantially improve flow velocity, thermal conductivity, and solute diffusion compared to di- and mono-nanoparticles, with tri-nanofluids exhibiting the most optimal overall performance.
  • No Thumbnail Available
    Item
    Computational simulation of heat transfer and nanofluid flow for two-sided lid-driven square cavity under the influence of magnetic field
    (De Gruyter, 2025-08) Sharma, Bhupendra Kumar
    The present study investigates the heat transfer for the unsteady, incompressible, two-dimensional mixed convective copper–water nanofluid flow in a lid-driven square cavity in the presence of the magnetic field. The lid-driven square cavity’s top and bottom walls are assumed to be adiabatic. The nanofluid model is developed in ANSYS-FLUENT using Boussinesq approximation. A pressure-based solver with a Semi-Implicit Method for Pressure-Linked Equations algorithm is used to simulate the governing equations of the model. The results obtained from the developed fluid model are examined for the different influential physical parameters to enhance heat transfer from the cavity to the flowing fluid. Qualitative and quantitative results for nanofluid concentration, magnetic field parameter, and Reynolds number are analyzed. A noteworthy observation is that the velocity of the nanofluid reduces with improvement in the magnetic field strength. The findings of the attempt provide the capability of nanofluids in heat transfer, which aids in creating innovative geometries with improved and regulated heat transfer due to applied magnetic fields. This attempt holds potential applications in solar collectors, electrical devices, and the medical field manageable due to the slower fluid flow (nanofluid).
  • No Thumbnail Available
    Item
    Computational analysis of radiative heat transfer due to rotating tube in parabolic trough solar collectors with Darcy Forchheimer porous medium
    (Elsevier, 2023-11) Sharma, Bhupendra Kumar
    This attempt numerically investigates the heat transfer in parabolic trough solar collectors due to the rotating tube for the hybrid nanofluid flow over the Riga surface with Darcy Forchheimer’s porous medium under the effect of solar radiation. The influences of viscous dissipation and Joule heating are also considered. Equations governing the fluid flow are non-dimensionalized by implementing appropriate similarity variables. The resulting non-dimensionalized ordinary differential equations are solved using the shooting technique with Adam Bashforth and Adam Moulten’s fourth-order numerical approach. The numerical outcomes for various influential physical parameters regarding the fluid velocity, temperature, Nusselt number, and entropy generation are presented in graphical form. It is observed that the thermal profile escalates with the higher values of Reynold’s number, modified magnetic field parameter, and Prandtl number. Also, the Nusselt number diminishes with augmenting values of the Eckert number, modified magnetic field parameter, Forchheimer number, and Darcy number. The optimization of heat transfer in parabolic trough collectors is essential to improve the performance of solar collectors. The concentrated solar power technology is adequate for storing radiation energy in higher amounts.
  • No Thumbnail Available
    Item
    Influence of magnetohydrodynamics and chemical reactions on oscillatory free convective flow through a vertical channel in a rotating system with variable permeability
    (World Scientific, 2024) Sharma, Bhupendra Kumar
    This study investigates the impact of variable permeability as well as chemical reactions on the oscillatory free convective flow that passes parallel porous flat plates with fluctuating temperature and concentration in the presence of a magnetic field. A vertical channel is assumed to be rotating at an angular velocity Ω. Periodic free stream velocity causes oscillations in one plate, while periodic suction velocity causes oscillations in the other plate. Complex variable notations are used to solve the governing equations. The perturbation technique is used to derive analytical expressions for the temperature, concentration, and velocity fields. In this study, various parameters were investigated in relation to mean velocity, mean temperature, mean concentration, amplitude, and phase difference. The study also examines the impact on secondary velocity, primary velocity, temperature, concentration, and heat transfer rate during transients. The outcomes are presented graphically for the physical parameters of the problem. The findings contribute to optimizing systems and improving efficiency in heat transfer, fluid dynamics, and environmental remediation.
  • No Thumbnail Available
    Item
    Investigating the impact of fin configuration on phase change material melting in square cells: A numerical study
    (Elsevier, 2025-01) Sharma, Bhupendra Kumar
    This investigation thoroughly explores the effects of different fin arrangements on the melting behavior of phase change materials (PCMs), specifically paraffin wax (RT42), within a 50 × 50 mm2 square cell. Three distinct cases are considered: Case 1 involves no fins, Case 2 incorporates straight rectangular fins, and Case 3 employs undulated fins. To simulate real-world thermal energy storage conditions, the PCM container is thermally insulated, preventing external heat leakage. The primary objective is to identify the optimal fin arrangement to enhance latent heat storage system efficiency by improving both melting and solidification processes. The novelty of this research lies in the detailed analysis of various undulated fin geometries and their placements, which have not been extensively explored in previous studies. Numerical simulations were conducted using the ANSYS FLUENT solver. The progression of PCM melting was evaluated via the ANSYS design modeler based on the finite volume method, incorporating transient heat conduction and free convection. The results demonstrate that optimized undulated fin configurations can significantly enhance the melting process by promoting uniform temperature distribution and improving heat transfer rates, thereby reducing melting time. This study provides valuable insights for designing efficient latent heat energy storage systems, contributing to advancements in energy management and sustainable technologies.
  • No Thumbnail Available
    Item
    Unsteady MHD Hybrid Nanoparticle (Au-Al2 O3 /Blood) Mediated Blood Flow Through a Vertical Irregular Stenosed Artery: Drug Delivery Applications
    (Springer, 2022-10) Sharma, Bhupendra Kumar
    The current study investigates the influence of hybrid nanoparticles (Au & Al2O3) on blood flow through a vertical artery with irregular stenosis with two-dimensional pulsatile blood flow, an inclined external magnetic field, viscous dissipation, and Joule heating. The blood flow is assumed to be unsteady, laminar, viscous, and incompressible, and the artery walls are considered permeable. The Reynolds temperature-dependent viscosity model is used to determine the variable viscosity effects. The governing momentum and energy equations are solved using Crank–Nicolson finite difference method by employing an appropriate coordinate transformation to build an accurate mesh using rectangular mesh units. Outcomes of the work are represented graphically for non-dimensional velocity, wall shear stress, flow rate, and non-dimensional temperature, respectively. The recent findings could be useful to biological researchers looking into the therapy of different cardiovascular disorders.
  • No Thumbnail Available
    Item
    Injection and suction e ects on three-dimensional unsteady ow and heat transfer between two parallel porous plates
    (Redalyc, 2003) Sharma, Bhupendra Kumar
    The problem of unsteady three-dimensional ow of an incompressible viscous uid between two horizontal parallel porous plates with transverse sinusoidal injection of the uid at the stationary plate and with constant suction through the plate in uniform motion has been studied. The moving plate is kept at oscillating wall temperature while the stationary plate is at constant temperature. Analytical expressions for velocity, temperature, and rate of heat transfer are obtained and discussed with the help of graphs and tables
  • No Thumbnail Available
    Item
    MHD blood flow and heat transfer through an inclined porous stenosed artery with variable viscosity
    (ARXIV, 2018-05) Sharma, Bhupendra Kumar
    In this article, effects of heat transfer on MHD blood flow through a stenosed inclined porous artery with heat source have been investigated. The viscosity of the blood is assumed to be varying radially with hematocrit throughout the region of the artery. Governing equations have been derived by treating blood as incompressible magnetohydrodynamic (MHD) Newtonian fluid. Momentum and energy equations of the fluid flow are simplified under the assumption of mild stenosis. Homotopy perturbation method (HPM) is used to solve nonlinear differential equations for velocity and temperature profiles of the blood flow. Variation of flow rate and shear stress for different values of inclination angle and hematocrit parameter along the diseased part of artery have been plotted graphically. For having the adequate insight of the flow pattern in the diseased artery, velocity contours have been plotted for different values of the height of the stenosis and for different inclination angles of the artery.
  • No Thumbnail Available
    Item
    Effects of Fluctuating Surface Temperature and Concentration on Unsteady Convection Flow Past an Infinite Vertical Plate with Constant Suction
    (Begell House, 2009) Sharma, Bhupendra Kumar
    Combined heat and mass transfer along an infinite vertical porous plate have been investigated when the temperature and concentration are assumed to oscillate in time about a constant mean. Assuming constant suction at the plate, approximate solutions are calculated by the perturbation method for transient velocity, temperature and concentration. The effects of various parameters on transient velocity, temperature, concentration, skin-friction, and rate of heat transfer have been discussed with the help of graphs and tables.
  • No Thumbnail Available
    Item
    Mathematical analysis of two-phase blood flow through a stenosed curved artery with hematocrit and temperature dependent viscosity
    (IOP, 2021) Sharma, Bhupendra Kumar
    Atwo-phase blood flow model is considered to analyze the fluid flow and heat transfer in a curved tube with time-variant stenosis. In both core and plasma regions, the variable viscosity model (Hematocrit and non linear temperature-dependent, respectively) is considered. A toroidal coordinate system is considered to describe the governing equations. The perturbation technique in terms of perturbation parameter ε is used to obtain the temperature profile of blood flow. In order to find the velocity, wall shear stress and impedance profiles, a second-order finite difference method is employed with the accuracy of 10−6 in the each iteration. Under the conditions of fully-developed flow and mild stenosis, the significance of various physical parameters on the blood velocity, temperature, wall shear stress (WSS) and impedance are investigated with the help of graphs. A validation of our results has been presented and comparison has been made with the previously published work and present study, and it revels the good agreement with published work. The present mathematical study suggested that arterial curvature increase the fear of deposition of plaque (atherosclerosis), while, the use of thermal radiation in heat therapies lowers this risk. The positive add in the value of λ1 causes to increase in plasma viscosity; as a result, blood flow velocity in the stenosed artery decreases due to the assumption of temperature-dependent viscosity of the plasma region. Clinical researchers and biologists can adopt the present mathematical study to lower the risk of lipid deposition, predict cardiovascular disease risk and current state of disease by understanding the symptomatic spectrum, and then diagnose patients based on the risk.