Heat flux measurements of Tb3M series (M=Co, Rh and Ru): Specific heat and magnetocaloric properties

The results of our work and a number of foreign studies indicate that the sharp increase in the heat transfer parameters (specific heat flux q and heat transfer coefficient _) at the boiling of nanofluids as compared to the base liquid (water) is due not only and not so much to the increase of the thermal conductivity of the nanofluids, but an intensification of the boiling process caused by a change in the state of the heating surface, its topological and chemical properties (porosity, roughness, wettability). The latter leads to a change in the internal characteristics of the boiling process and the average temperature of the superheated liquid layer. This circumstance makes it possible, on the basis of physical models of the liquids boiling and taking into account the parameters of the surface state (temperature, pressure) and properties of the coolant (the density and heat capacity of the liquid, the specific heat of vaporization and the heat capacity of the vapor), and also the internal characteristics of the boiling of liquids, to calculate the value of specific heat flux q. In this paper, the difference in the mechanisms of heat transfer during the boiling of single-phase (water) and two-phase nanofluids has been studied and a quantitative estimate of the q values for the boiling of the nanofluid is carried out based on the internal characteristics of the boiling process. The satisfactory agreement of the calculated values with the experimental data is a confirmation that the key factor in the growth of the heat transfer intensity at the boiling of nanofluids is indeed a change in the nature and microrelief of the heating surface. Bibl. 20, Fig. 9, Tab. 2.

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QUANTIFYING ERRORS IN HEAT FLUX MEASUREMENTS USING A VERTICAL SEQUENCE OF THERMOCOUPLE SENSORS

10.1130/abs/2016rm-276188 ◽

2016 ◽

Author(s):

Gabriela Villegas ◽

◽

Jerry P. Fairley ◽

Cary R. Lindsey ◽

Megan M. Aunan ◽

...

Keyword(s):

Heat Flux ◽

Flux Measurements

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Fast-Response transient heat flux measurements in a plasma wind tunnel

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2021.121234 ◽

2021 ◽

Vol 173 ◽

pp. 121234

Author(s):

Byrenn Birch ◽

David Buttsworth ◽

Stefan Löhle ◽

Fabian Hufgard

Keyword(s):

Heat Flux ◽

Wind Tunnel ◽

Fast Response ◽

Flux Measurements ◽

Transient Heat Flux

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An analog period method for gap‐filling of latent heat flux measurements

Hydrological Processes ◽

10.1002/hyp.14105 ◽

2021 ◽

Author(s):

Lucas Emilio B. Hoeltgebaum ◽

Nelson Luís Dias ◽

Marcelo Azevedo Costa

Keyword(s):

Heat Flux ◽

Latent Heat ◽

Latent Heat Flux ◽

Gap Filling ◽

Flux Measurements

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Model-based optimization of equipment and control for heat flux measurements in a laboratory fermentor

Biotechnology Progress ◽

10.1021/bp00035a005 ◽

1995 ◽

Vol 11 (5) ◽

pp. 525-532 ◽

Cited By ~ 6

Author(s):

Bastiaan H. A. van Kleeff ◽

J. Gijs Kuenen ◽

Ger Honderd ◽

Sef J. Heijnen

Keyword(s):

Heat Flux ◽

Model Based ◽

Flux Measurements ◽

And Control ◽

Laboratory Fermentor

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Ice-Giants Net Flux Radiometer for Heat Flux Measurements

10.5194/epsc2021-144 ◽

2021 ◽

Author(s):

Shahid Aslam ◽

Simon Calcutt ◽

Nicolas Gorius ◽

Patrick Irwin ◽

George Nehmetallah ◽

...

Keyword(s):

Heat Flux ◽

Flux Measurements ◽

Net Flux

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The impact of broadleaved woodland on water resources in lowland UK: II. Evaporation estimates from sensible heat flux measurements over beech woodland and grass on chalk sites in Hampshire

Hydrology and Earth System Sciences ◽

10.5194/hess-9-607-2005 ◽

2005 ◽

Vol 9 (6) ◽

pp. 607-613 ◽

Cited By ~ 12

Author(s):

J. Roberts ◽

P. Rosier ◽

D. M. Smith

Keyword(s):

Heat Flux ◽

Energy Balance ◽

Excellent Agreement ◽

Sensible Heat Flux ◽

Late Summer ◽

Eddy Correlation ◽

Sensible Heat ◽

Flux Measurements ◽

Shallow Soils ◽

The Impact

Abstract. The impact on recharge to the Chalk aquifer of substitution of broadleaved woodland for pasture is a matter of concern in the UK. Hence, measurements of energy balance components were made above beech woodland and above pasture, both growing on shallow soils over chalk in Hampshire. Latent heat flux (evaporation) was calculated as the residual from these measurements of energy balances in which sensible heat flux was measured with an eddy correlation instrument that determined fast response vertical wind speeds and associated temperature changes. Assessment of wind turbulence statistics confirmed that the eddy correlation device performed satisfactorily in both wet and dry conditions. There was excellent agreement between forest transpiration measurements made by eddy correlation and stand level tree transpiration measured with sap flow devices. Over the period of the measurements, from March 1999 to late summer 2000, changes in soil water content were small and grassland evaporation and transpiration estimated from energy balance-eddy flux measurements were in excellent agreement with Penman estimates of potential evaporation. Over the 18-month measurement period, the cumulative difference between broadleaved woodland and grassland was small but evaporation from the grassland was 3% higher than that from the woodland. In the springs of 1999 and 2000, evaporation from the grassland was greater than that from the woodland. However, following leaf emergence in the woodland, the difference in cumulative evaporation diminished until the following spring.

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