Unaxisymmetric stagnation-point flow and heat transfer of a viscous fluid with variable viscosity on a cylinder
Existing solutions of the problem of axisymmetric stagnation-point flow and heat transfer on either a cylinder or a flat plate are for incompressible fluid. Here, fluid with viscosity proportional to a linear function of temperature is considered in the problem of an unaxisymmetric stagnation-point...
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| Format: | Article |
| Language: | English |
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Elsevier
2016-06-01
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| Series: | Alexandria Engineering Journal |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S1110016816300734 |
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| author | Rasool Alizadeh Asghar B. Rahimi Reza Arjmandzadeh Mohammad Najafi Ahmad Alizadeh |
| author_facet | Rasool Alizadeh Asghar B. Rahimi Reza Arjmandzadeh Mohammad Najafi Ahmad Alizadeh |
| author_sort | Rasool Alizadeh |
| collection | DOAJ |
| description | Existing solutions of the problem of axisymmetric stagnation-point flow and heat transfer on either a cylinder or a flat plate are for incompressible fluid. Here, fluid with viscosity proportional to a linear function of temperature is considered in the problem of an unaxisymmetric stagnation-point flow and heat transfer of an infinite stationary cylinder with non-uniform normal transpiration U0(φ) and constant heat flux. The impinging free-stream is steady and with a constant strain rate k¯. A reduction of Navier–Stokes and energy equations is obtained by use of appropriate similarity transformations. The semi-similar solution of the Navier–Stokes equations and energy equation has been obtained numerically using an implicit finite-difference scheme. All the solutions aforesaid are presented for Reynolds numbers, Re=k¯a2/2υ∞, ranging from 0.01 to 100 for different values of Prandtl number and viscosity-variation parameter and for selected values of transpiration rate function, S(φ)=U0(φ)/k¯a, where a is cylinder radius and υ∞ is the reference kinematic viscosity of the fluid. Dimensionless shear-stresses corresponding to all the cases increase with the increase in Reynolds number and transpiration rate function while dimensionless shear stresses decrease with the increase in viscosity-variation parameter. The local coefficient of heat transfer (Nusselt number) increases with increasing the transpiration rate function and Prandtl number. |
| first_indexed | 2024-12-19T10:21:40Z |
| format | Article |
| id | doaj.art-ee3f4d88f3fe4c7fb18541c37d33b362 |
| institution | Directory Open Access Journal |
| issn | 1110-0168 |
| language | English |
| last_indexed | 2024-12-19T10:21:40Z |
| publishDate | 2016-06-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Alexandria Engineering Journal |
| spelling | doaj.art-ee3f4d88f3fe4c7fb18541c37d33b3622022-12-21T20:26:03ZengElsevierAlexandria Engineering Journal1110-01682016-06-015521271128310.1016/j.aej.2016.04.017Unaxisymmetric stagnation-point flow and heat transfer of a viscous fluid with variable viscosity on a cylinderRasool Alizadeh0Asghar B. Rahimi1Reza Arjmandzadeh2Mohammad Najafi3Ahmad Alizadeh4Department of Mechanical Engineering, Quchan Branch, Islamic Azad University, Quchan, IranFaculty of Engineering, Ferdowsi University of Mashhad, P.O. Box No. 91775-1111, Mashhad, IranDepartment of Geology, Payame Noor University (PNU), IranDepartment of Mechanical and Aerospace Engineering, Tehran Science and Research Branch, Islamic Azad University, Tehran, IranYoung Researchers Club, Quchan Branch, Islamic Azad University, Quchan, IranExisting solutions of the problem of axisymmetric stagnation-point flow and heat transfer on either a cylinder or a flat plate are for incompressible fluid. Here, fluid with viscosity proportional to a linear function of temperature is considered in the problem of an unaxisymmetric stagnation-point flow and heat transfer of an infinite stationary cylinder with non-uniform normal transpiration U0(φ) and constant heat flux. The impinging free-stream is steady and with a constant strain rate k¯. A reduction of Navier–Stokes and energy equations is obtained by use of appropriate similarity transformations. The semi-similar solution of the Navier–Stokes equations and energy equation has been obtained numerically using an implicit finite-difference scheme. All the solutions aforesaid are presented for Reynolds numbers, Re=k¯a2/2υ∞, ranging from 0.01 to 100 for different values of Prandtl number and viscosity-variation parameter and for selected values of transpiration rate function, S(φ)=U0(φ)/k¯a, where a is cylinder radius and υ∞ is the reference kinematic viscosity of the fluid. Dimensionless shear-stresses corresponding to all the cases increase with the increase in Reynolds number and transpiration rate function while dimensionless shear stresses decrease with the increase in viscosity-variation parameter. The local coefficient of heat transfer (Nusselt number) increases with increasing the transpiration rate function and Prandtl number.http://www.sciencedirect.com/science/article/pii/S1110016816300734Unaxisymmetric stagnation-point flowHeat transferStationary cylinderTemperature dependent viscosityNumerical solutionNon-uniform transpiration |
| spellingShingle | Rasool Alizadeh Asghar B. Rahimi Reza Arjmandzadeh Mohammad Najafi Ahmad Alizadeh Unaxisymmetric stagnation-point flow and heat transfer of a viscous fluid with variable viscosity on a cylinder Alexandria Engineering Journal Unaxisymmetric stagnation-point flow Heat transfer Stationary cylinder Temperature dependent viscosity Numerical solution Non-uniform transpiration |
| title | Unaxisymmetric stagnation-point flow and heat transfer of a viscous fluid with variable viscosity on a cylinder |
| title_full | Unaxisymmetric stagnation-point flow and heat transfer of a viscous fluid with variable viscosity on a cylinder |
| title_fullStr | Unaxisymmetric stagnation-point flow and heat transfer of a viscous fluid with variable viscosity on a cylinder |
| title_full_unstemmed | Unaxisymmetric stagnation-point flow and heat transfer of a viscous fluid with variable viscosity on a cylinder |
| title_short | Unaxisymmetric stagnation-point flow and heat transfer of a viscous fluid with variable viscosity on a cylinder |
| title_sort | unaxisymmetric stagnation point flow and heat transfer of a viscous fluid with variable viscosity on a cylinder |
| topic | Unaxisymmetric stagnation-point flow Heat transfer Stationary cylinder Temperature dependent viscosity Numerical solution Non-uniform transpiration |
| url | http://www.sciencedirect.com/science/article/pii/S1110016816300734 |
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