Theoretical solution of simultaneous heat and mass transfer by free convection about a vertical flat plate

Bottemanne, F.A.

doi:10.1007/bf00382290

Cited by 36 publications

(7 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, the most comprehensive similarity solutions for this problem are those presented by Gebhart and Pera (1971). Also, Bottemanne (1972) presented experimental results of pure and simultaneous heat and mass transfer by free convection about a vertical cylinder for Prandtl number Pr = 0.71 and Schmidt number S = 0.63, which are in agreement with theoretical results reported by Bottemanne (1971).…”

Section: Introductionsupporting

confidence: 77%

“…Theoretical work on the boundary-layer-type solutions of double-diffusive convection over vertical flat surfaces reported so far is restricted to either integral techniques (Wilcox, 1961; Somers, 1956) or similarity formulations (Adams and Lowel, 1968; Bottemanne, 1971). However, the most comprehensive similarity solutions for this problem are those presented by Gebhart and Pera (1971).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Mixed convection flow, heat transfer, species concentration near the stagnation point on a vertical flat plate with Stefan coupled blowing

Roşca

Merkin

et al. 2017

HFF

View full text Add to dashboard Cite

Purpose The purpose of this study is to consider the effects that buoyancy arising from the combination of both thermal and concentration gradients can have on the mixed convection boundary-layer flow near a forward stagnation point with the effect of Stefan blowing being included. Ad suitable choice for the functional forms of the outer flow and the wall temperature and concentration enables the problem to be reduced to a similarity form involving the dimensionless parameters, λ (mixed convection), κ (Stefan blowing) and N (relative strength of concentration driven buoyancy to that of thermal driven), as well as the Prandtl and Schmidt numbers. Numerical solutions to this similarity system for a range of representative parameter values indicate a finite, non-zero range of κ where there can be four solutions in opposing flow with only one solution in aiding flow. Asymptotic solutions for large values of N and κ are derived, the latter having two different structures in the opposing flow. Design/methodology/approach This paper sets up a similarity problem to examine the effects of Stefan blowing on a mixed convection flow with the aims of solving the equations numerically and complementing the results with appropriate asymptotic analysis. Findings The findings of the study include multiple solution branches, saddle-node bifurcations and singularities appearing in the solution. Originality/value The authors believe that all the results, both numerical and asymptotic, are original and have not been published elsewhere.

show abstract

Section: Introductionsupporting

confidence: 77%

Section: Introductionmentioning

confidence: 99%

Mixed convection flow, heat transfer, species concentration near the stagnation point on a vertical flat plate with Stefan coupled blowing

Roşca

Merkin

et al. 2017

HFF

View full text Add to dashboard Cite

show abstract

“…Chemical heat and mass transfer in natural convection flows on vertical cylinders has a wide range of applications in the field of science and technology [1]. In systems where a chemical reaction of dissociation recombination takes place, the total heat transfer may be increased to the energy transfer by diffusion under the influence of a concentration gradient.…”

Section: Introductionmentioning

confidence: 99%

“…A fiew representative fields of interest in which combined heat and mass transfer along with chemical reaction play an important role in chemical process industries such as food processing and polymer production. Bottemanne [1] gave the experimental results for a vertical cylinder with simultaneous heat and mass transfer and evaporation of water vapour into still air with Prandtl number (P r = 0.71) and Schmidt number (S c = 0.63) under the uniform wall temperature/concentration condition. Bottemanne's [1] experiments were conducted using a cylinder of "large diameter".…”

Section: Introductionmentioning

confidence: 99%

“…Bottemanne [1] gave the experimental results for a vertical cylinder with simultaneous heat and mass transfer and evaporation of water vapour into still air with Prandtl number (P r = 0.71) and Schmidt number (S c = 0.63) under the uniform wall temperature/concentration condition. Bottemanne's [1] experiments were conducted using a cylinder of "large diameter". The effects of mass transfer on the flow past an impulsively started infinite vertical plate under constant heat flux condition along with chemical reaction were studied by Das et al [2].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Effects of Chemical Reaction on the Unsteady Free Convection Flow past an Infinite Vertical Permeable Moving Plate with Variable Temperature

El-Fayez¹

2012

JSEMAT

View full text Add to dashboard Cite

Analytical solutions for the effect of chemical reaction on the unsteady free convection flow past an infinite vertical permeable moving plate with variable temperature has been studied. The plate is assumed to move with a constant velocity in the direction of fluid flow. The highly nonlinear coupled differential equations governing the boundary layer flow, heat and mass transfer are solved using two-term harmonic and non-harmonic functions. The parameters that arise in the perturbation analysis are Prandtl number (thermal diffusivity), Schmidt number (mass diffusivity), Grashof number (free convection), modified Grashof number, Chemical reaction parameter (rate constant), Skin friction coefficient and Sherwood number (wall mass transfer coefficient). The study has been compared with available exact solution in the literature and they are found to be in good agreement. It is observed that: The concentration increases during generative reaction and decreases in destructive reaction. The concentration increases with decreasing Schmidt number. The effect of increasing values of K leads to a fall in velocity profiles. The velocity decreases with increasing values of the Schmidt number. An increase in modified Grashof number leads to an increase in velocity profiles. The skin friction increases with decreasing Schmidt number. In generative reaction the skin friction decreases and in destructive reaction the skin friction increases

show abstract

The stability of a vertical flow which arises from combined buoyancy modes

Boura¹,

Gebhart

1976

AIChE Journal

View full text Add to dashboard Cite

We consider a mass transfer induced buoyancy force, superimposed on a thermally induced one, in a flow generated adjacent to a vertical surface. Flow and stability were investigated for a Prandtl number of 0.7; for Schmidt numbers of 2.0, 0.94, and 0.2; and for different magnitudes of the buoyancy effects. SCOPEMass transfer occurring in a body of fluid gives rise to a buoyancy force if the concentration gradient causes density differences. If the concentration of the diffusing species is sufficiently small, the equations governing the phenomenon are identical to those governing a thermally induced flow. A frequently occurring circumstance in our environment and in technological applications is the simultaneous transport of both thermal energy and a chemical constituent. The two buoyancy effects may be in the same direction or opposing. They may even have different spatial extent in the fluid if the Prandtl and Schmidt numbers are different.The consequences, the effects on the resulting flow and on its stability to disturbances whose growth determines transition to turbulence, were investigated for a gas. Mass transfer effects were determined over the known range of mass transfer rates, that is, of Schmidt number.The analyses predict transport rates as well as the conditions of instability and the actual disturbance growth rates. These results amount to an assessment of those complicated and interacting effects over a wide range of practical applications. Previous developments are summarized in a later section, preceding the analysis. PREVIOUS WORKOne of the first investigations of the flow resulting from combined buoyancy modes was by Somers (1956), who applied integral method analysis to predict the flow that would arise adjacent to a wetted isothermal surface. Mathers et al. (1957) and Wilcox (1961) using, respectively, an analogue and an integral analysis, follow Somers in as- Gebhart. the total buoyancy term in the momentum equation. Such All correspondence concerning this paper should be addressed to B. signing a factor +% to the transport contribution to formation and predicted the observed weak temperature dependence of fuel nitrogen conversion, as well as a significant effect of particle size,

show abstract

Theoretical solution of simultaneous heat and mass transfer by free convection about a vertical flat plate

Cited by 36 publications

References 3 publications

Mixed convection flow, heat transfer, species concentration near the stagnation point on a vertical flat plate with Stefan coupled blowing

Mixed convection flow, heat transfer, species concentration near the stagnation point on a vertical flat plate with Stefan coupled blowing

Effects of Chemical Reaction on the Unsteady Free Convection Flow past an Infinite Vertical Permeable Moving Plate with Variable Temperature

The stability of a vertical flow which arises from combined buoyancy modes

Contact Info

Product

Resources

About