Pulsating flow and heat transfer analysis around a heated semi-circular cylinder at low and moderate Reynolds numbers

This paper describes the addition of conjugate capability to an existing Navier-Stokes code. Also, results are presented for an internally cooled configuration. The code is currently referred to as the Glenn-HT code, because of its origin at the NASA Glenn Research center and its proven ability to predict flow and Heat Transfer. In the past, the code had been called traf3d.mb. The addition of the conjugate capability to the code was accomplished with a minimum amount of changes to the code, with the understanding that if more advanced techniques were required they could be added at a later date. In the solid region, the density is constant and the velocities are of course zero which leaves only a simplified form of the energy equation to be solved. This simplified energy equation is solved using the same method as in the gas regions with only minor changes to the numerical parameters. At the interface between the gas and solid the wall temperature is set so as to produce the same heat flux in each region. Results are presented for a pipe flow to validate the implementation. Numerical and experimental results are then presented for flow over a flat plate that is cooled internally. Flat plate Reynolds numbers in the range 180,000 to 950,000, and coolant channel Reynolds numbers in the range 30,000 to 60,000 are presented.

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Turbulent fluid flow and heat transfer analysis of heated rectangular blocks encountered in electronics enclosures

E3S Web of Conferences ◽

10.1051/e3sconf/202018401027 ◽

2020 ◽

Vol 184 ◽

pp. 01027

Author(s):

B Ch Nookaraju

Keyword(s):

Heat Transfer ◽

Nusselt Number ◽

Kinetic Energy ◽

Vertical Channel ◽

Reynolds Numbers ◽

Heat Transfer Analysis ◽

Computational Investigation ◽

Turbulent Fluid Flow ◽

Flow And Heat Transfer ◽

Pressure Fall

Computational investigation of steady, two-dimensional heat transfer attributes for forced convective chaotic discharge in a vertical channel of cluster of heated rectangular sections is performed. The discharge is deemed to be periodic fully developed so that the issue is determined for two extending zone and explanation is developed to more number of sections. This structure reproduces the driven convective cooling of a cluster of engraved circuit panels confronted in computerize belongings. Two mathematical statements for k- ℇ model is used for modeling for the turbulence and the finite volume methodology is used. Computations are performed for Reynolds numbers ranging from 6000-12000, Prandtl number of 0.7 and various geometric parameters characterizing the problem. As Reynolds number steps up the Nusselt Number increases. Re-circulations undermine the local Nusselt number when matched with comparing variation from a identical plate. The velocity contours, temperature distributions, variation of turbulent kinetic energy and kinetic energy dissipation rates in a vertical channel is found. With the blocks in the cluster, pressure fall is higher in resemblance to plane duct.

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Flow and Heat Transfer Around a Circular Cylinder in a Pulsating Flow of Low Reynolds Number

Transactions of the Japan Society of Mechanical Engineers ◽

10.1299/kikai1938.43.1103 ◽

1977 ◽

Vol 43 (367) ◽

pp. 1103-1114

Author(s):

Tomio OBOKATA ◽

Atsushi OKAJIMA ◽

Yoshimichi TANIDA

Keyword(s):

Heat Transfer ◽

Reynolds Number ◽

Circular Cylinder ◽

Low Reynolds Number ◽

Pulsating Flow ◽

Flow And Heat Transfer ◽

Low Reynolds

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On the Organization of Flow and Heat Transfer in the Near Wake of a Circular Cylinder in Steady and Pulsed Flow

Journal of Fluids Engineering ◽

10.1115/1.2910036 ◽

1992 ◽

Vol 114 (3) ◽

pp. 348-355 ◽

Cited By ~ 9

Author(s):

D. P. Telionis ◽

M. Gundappa ◽

T. E. Diller

Keyword(s):

Heat Transfer ◽

Circular Cylinder ◽

Skin Friction ◽

Power Spectra ◽

Reynolds Numbers ◽

Driving Frequency ◽

Near Wake ◽

Flow And Heat Transfer ◽

Pulsed Flow ◽

Oncoming Stream

Skin friction, pressure, and heat transfer gages are employed to monitor the flow and heat transfer field along the periphery of a circular cylinder in steady and pulsed flow at Reynolds numbers, Re = 23,000 to 50,000. Averaged distributions, RMS, and power spectra of all measurements are displayed. Special attention is directed at the organization of the near wake, as detected by the three types of surface gages. The response of the wake to pulsing of the oncoming stream is also examined. It is found that when the wake is locked on the driving frequency, the basic character of the flow is not changed, but the organized motion stands out more clearly. Moreover, the signals become cleaner and background noise in the spectra is reduced. Skin friction and heat transfer gages are shown to respond to local variations of the corresponding quantities, whereas pressure gages respond to global characteristics of the flow.

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