Effects of mass transfer on a resonance instability in the laminar boundary layer flow over a rotating-disk

Three-dimensional boundary-layer flow is well known for its abrupt and sharp transition from laminar to turbulent regime. The presented study is a first attempt to achieve the target of delaying the natural transition to turbulence. The behaviour of two different shaped and sized stationary disturbances (in the laboratory frame) on the rotating-disk boundary layer flow is investigated. These disturbances are placed at dimensionless radial location (Rf = 340) which lies within the convectively unstable zone over a rotating-disk. Mean velocity profiles were measured using constant-temperature hot-wire anemometry. By careful analysis of experimental data, the instability of these disturbance wakes and its estimated orientation within the boundary-layer were investigated.

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Impact of Binary Chemical Reaction and Activation Energy on Heat and Mass Transfer of Marangoni Driven Boundary Layer Flow of a Non-Newtonian Nanofluid

Processes ◽

10.3390/pr9040702 ◽

2021 ◽

Vol 9 (4) ◽

pp. 702

Author(s):

Ramanahalli Jayadevamurthy Punith Gowda ◽

Rangaswamy Naveen Kumar ◽

Anigere Marikempaiah Jyothi ◽

Ballajja Chandrappa Prasannakumara ◽

Ioannis E. Sarris

Keyword(s):

Heat Transfer ◽

Activation Energy ◽

Boundary Layer ◽

Mass Transfer ◽

Heat And Mass Transfer ◽

Velocity Gradient ◽

Boundary Layer Flow ◽

Biological Fluids ◽

Porosity Parameter ◽

Layer Flow

The flow and heat transfer of non-Newtonian nanofluids has an extensive range of applications in oceanography, the cooling of metallic plates, melt-spinning, the movement of biological fluids, heat exchangers technology, coating and suspensions. In view of these applications, we studied the steady Marangoni driven boundary layer flow, heat and mass transfer characteristics of a nanofluid. A non-Newtonian second-grade liquid model is used to deliberate the effect of activation energy on the chemically reactive non-Newtonian nanofluid. By applying suitable similarity transformations, the system of governing equations is transformed into a set of ordinary differential equations. These reduced equations are tackled numerically using the Runge–Kutta–Fehlberg fourth-fifth order (RKF-45) method. The velocity, concentration, thermal fields and rate of heat transfer are explored for the embedded non-dimensional parameters graphically. Our results revealed that the escalating values of the Marangoni number improve the velocity gradient and reduce the heat transfer. As the values of the porosity parameter increase, the velocity gradient is reduced and the heat transfer is improved. Finally, the Nusselt number is found to decline as the porosity parameter increases.

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Soret and Dufour effects on MHD boundary layer flow of non-Newtonian Carreau fluid with mixed convective heat and mass transfer over a moving vertical plate

Pramana ◽

10.1007/s12043-020-01984-z ◽

2020 ◽

Vol 94 (1) ◽

Author(s):

Anil Kumar Gautam ◽

Ajeet Kumar Verma ◽

Krishnendu Bhattacharyya ◽

Astick Banerjee

Keyword(s):

Boundary Layer ◽

Mass Transfer ◽

Heat And Mass Transfer ◽

Boundary Layer Flow ◽

Vertical Plate ◽

Carreau Fluid ◽

Soret And Dufour Effects ◽

Mhd Boundary Layer ◽

Layer Flow ◽

Mhd Boundary Layer Flow

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