Axial heat transfer in packed beds. Gas flow through beds between 20 and 650°C

Measurements of the resistance to flow through packed beds of inert spheres have been reported by a number of authors through relations expressing the coefficient of drag as a function of Reynolds number. A meta-analysis of the data using improved statistical methods is undertaken to aggregate the available experimental results. For Reynolds number in excess of 103 the relation log Fv = 0.49 + 0.90 log Re′ is shown to be a highly effective representation of all available data.

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Magnetogasdynamic Flow and Heat Transfer in a Microchannel

ASME 2011 9th International Conference on Nanochannels, Microchannels, and Minichannels, Volume 1 ◽

10.1115/icnmm2011-58221 ◽

2011 ◽

Author(s):

Huei Chu Weng

Keyword(s):

Magnetic Field ◽

Heat Transfer ◽

Joule Heating ◽

Electromagnetic Force ◽

Gas Flow ◽

Velocity Slip ◽

Flow And Heat Transfer ◽

Electric And Magnetic Field ◽

Flow Through ◽

Flow Drag

The presence of current flow in an electric and magnetic field results in electromagnetic force and joule heating. It is desirable to understand the roles of electromagnetic force and joule heating on gas microflow and heat transfer. In this study, a mathematical model is developed of the pressure-driven gas flow through a long isothermally heated horizontal planar microchannel in the presence of an external electric and magnetic field. The solutions for flow and thermal field and characteristics are derived analytically and presented in terms of dimensionless parameters. It is found that an electromagnetic driving force can be produced by a combined non-zero electric field and a negative magnetic field and results in an additional velocity slip and an additional flow drag. Also, a joule heating can be enhanced by an applied positive magnetic field and therefore results in an additional temperature jump and an additional heat transfer.

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Identification of character of flow realized in low power heating boilers

E3S Web of Conferences ◽

10.1051/e3sconf/201912801008 ◽

2019 ◽

Vol 128 ◽

pp. 01008

Author(s):

Wojciech Judt ◽

Bartosz Ciupek ◽

Rafał Urbaniak

Keyword(s):

Heat Transfer ◽

Low Power ◽

Transfer Process ◽

Gas Flow ◽

Heat Transfer Process ◽

Vertical Position ◽

Exhaust Gas ◽

Flow Through ◽

Heating Boiler ◽

Different Levels

An analysis of a heat transfer process during exhaust gas flow through two boiler draughts connected in the reversing chamber is presented. The article shows the main differences in the exhaustgas flowthrough the boiler construction when heating boiler works with different levels of heating power.The aim of the proposed research is defining a character of a flow and a heat transfer process depending onthe horizontal and vertical position of boiler draughts.

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Axial heat transfer in packed beds. Stagnant beds between 20 and 750°C

International Journal of Heat and Mass Transfer ◽

10.1016/0017-9310(71)90207-9 ◽

1971 ◽

Vol 14 (8) ◽

pp. 1093-1113 ◽

Cited By ~ 27

Author(s):

G.S.G Beveridge ◽

D.P Haughey

Keyword(s):

Heat Transfer ◽

Packed Beds ◽

Axial Heat

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Heat Transfer and Pressure Drop Through Nano-Fin Arrays in the Free-Molecular Flow Regime

ASME 2012 Third International Conference on Micro/Nanoscale Heat and Mass Transfer ◽

10.1115/mnhmt2012-75312 ◽

2012 ◽

Author(s):

Michael James Martin

Keyword(s):

Heat Transfer ◽

Pressure Drop ◽

Gas Flow ◽

Ideal Gas ◽

Molecular Flow ◽

Ideal Gas Law ◽

Transfer Equations ◽

Flow Through ◽

The One ◽

The Ideal

Gas flow through arrays of rectangular nano-fins is modeled using the linearized free-molecular drag and heat transfer equations. These are combined with the one-dimensional equations for conservation of mass, momentum, and energy, and the ideal gas law, to find the governing equations for flow through the array. The results show that the pressure gradient, temperature, and local velocity of the gas are governed by coupled ordinary differential equations. The system of equations is solved for representative arrays of nano-fins to find the total heat transfer and pressure drop across a 1 cm chip.

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