Applied Mathematics, Mathematical Physics, Numerical Analysis, Fluid Flow and Transfer Processes
FUTURE PROJECTS
Blood Flow through an annular region
Applications Invited
18
Scopus Publications
Scopus Publications
MHD nanofluid flow with energy transfer over a porous stretching surface by using a second-grade fluid model Debasish Dey, Rupjyoti Borah Numerical Heat Transfer Part A Applications, 2025 The main attention of this research is to examine the nature of the flow behavior of nanofluids and energy transfers past an expanding sheet with second-grade fluid model. The system is also situated in an absorbent area, which affects the effects of heat and mass transport and chemical reaction. The numerical calculations and visualization for various flow parameters are performed using a finite difference code that is developed in the built-in bvp4c solver scheme of MATLAB. This involves adopting a set of new variables to change the character of the governing equations of this study. To the best of the authors’ knowledge, many authors have contributed to this field, but they do not take into account the above fluid model associated with the energy transfers with the influences of Brownian motion, thermophoresis effect, and chemical reaction parameters, etc., in their study. Major findings of this study is to achieve a higher amount of thermal transference using the physical parameters, such as magnetic, visco-elastic, thermophoresis, and Brownian motion parameters, etc. Also, using smaller values of the magnetic parameter can be an effective way to minimize the impact of drag force of the fluid at the surface. The considering fluid model has multifarious industrial applications, such as food and cosmetic industry and pharmaceutical and biomedical industry, etc., due to its versatile rheological characteristics.
Flow of Casson nanofluid with energy transfer and slip effects over an exponentially porous expanding surface and its dual solutions Debasish Dey, Rupjyoti Borah Latin American Applied Research, 2025 The occurrence of dual solutions of the Casson nanofluid generated by an exponentially expanding surface located in an absorbent medium and second-order slip effects have been examined. In the transverse direction of the flow, a homogeneous magnetic field is taken into account. The model equations are modified using a suitable similarity transformation so that they may be computed using the bvp4c solver technique in MATLAB. The outcomes are presented graphically and in tabular form, along with some innovative flow variables. Two solutions have been identified using the stability analysis, one of which is both physically feasible and stable in nature. As a result of the investigation, it is clear that the fluid's ability to transmit heat is improved by the flow characteristics related to nanofluid. The considering fluid model is one of the best fluid models, as this model reduces the effects of shear stress at the surface during both first and second solutions and protecting the system from flow related damage. We performed a comparison to ensure the accuracy of our results and discovered a good match. The considering fluid model has significant applications in different physical fields such as heat exchangers, cooling of electronic devices and drug delivery in the human body etc. The flow behavior of Casson nanofluids over a stretching surface may lead to improved efficiency, reduced energy consumption and better product quality etc.
DUAL SOLUTIONS OF WATER-BASED MICROPOLAR NANOFLUID FLOW OVER A SHRINKING SHEET WITH THERMAL TRANSMISSION Stability Analysis Debasish Dey, Rupjyoti Borah Thermal Science, 2024 Investigation of the nature of dual solutions of the water-based micropolar nanofluid-flow with thermal transmission due to a contracting surface has been done in the work. The flow is characterized by its shrinking velocity and imposed magnetic field. Also, this work is one of the contributions that illustrate the microrotation and microinertia descriptions of nanofluids. The effects of metallic nanoparticles Cu and CuO have been discussed throughout this study. A uniform magnetic field has been applied in the normal direction of the flow. A set of basic equations that supports the present problem are derived from the principle of conservation laws and have been modernized into a set of solvable forms by employing suitable similarity variables. The MATLAB built-in bvp4c solver scheme is engineered to solve this problem. In order to tackle boundary value problems that are highly non-linear, this numerical method largely relies on collocation and finite difference techniques. From this study, we have perceived that the speed of the motion of CuO-water nanofluid in both cases (the first and second solutions) is less than CuO-water nanofluid. The material parameter plays an important role by enhancing the heat transfer rate of the fluid at the surface of the sheet in both time-dependent and time-independent cases. From the stability analysis, the first solution has been found as the stable and physically attainable solution. Additionally, the material parameter aids in reducing the effects of couple stress and shear stress on the fluid in both situations near the surface.
DUAL SOLUTIONS OF HYBRID NANOFLUID FLOW OVER A CONE WITH THE INFLUENCE OF THERMAL RADIATION AND CHEMICAL REACTION AND ITS STABILITY ANALYSIS Debasish Dey, Rupjyoti Borah, Ashim Jyoti Baruah East European Journal of Physics, 2023 The main intention of this study is to differentiate the stable and realisable solutions between the dual solutions of the water-based hybrid nanofluid flow driven by a solid cone along with energy transfer in the form of heat and mass by employing a new approach called stability analysis. The deviation of thermal radiation, chemical responses and heat absorption/generation are reserved into account. The leading equations which support the mathematical representation of this study are renovated by utilizing a set of similarity variables and solved by the MATLAB built-in bvp4c solver scheme. The outcomes of this study are presented both graphically and numerically. From this study, two kind of flow solutions have been achieved where one of them is related to the time-independent solutions and stable in nature. Also, the speed of the hybrid nanofluid can be controlled by applying magnetic field, but we should keep in mind that excessive amount of magnetic parameter may damage the system by burning.
