Heat Exchange in the System Mould – Riser – Ambient. Part I: Heat Exchange Coefficient from Mould External Surface

2013 ◽  
Vol 58 (3) ◽  
pp. 833-835 ◽  
Author(s):  
P.K. Krajewski ◽  
Z. Zovko-Brodarac ◽  
W.K. Krajewski
Keyword(s):  
Heat Exchange ◽  
Surface Temperature ◽  
Temperature Dependence ◽  
External Surface ◽  
Mass Density ◽  
Exchange Coefficient ◽  
Heat Exchange Coefficient ◽  
Surface Temperatures ◽  
The Subject ◽  
The Relationship

Abstract The subject of the paper is heat exchange in the system casting - riser - ambient. The examinations were focused on evaluating temperature dependence of the coefficient of heat exchange from mould external surface (or from riser thermally insulated surface) to ambient. The examinations were carried out for the surface temperatures of 200-800°. On the basis of the performed examinations it was stated that the relationship αext:eff vs. surface temperature can be described by a polynomial of 3rd degree with accuracy of 90-95% and that the αext:eff coefficient significantly depends on the examined material mass density.

scholarly journals On the Heat Exchange Between Rivers and Atmosphere

1982 ◽  
Vol 13 (2) ◽  
pp. 65-78
Author(s):  
Ole Stang
Keyword(s):  
Heat Exchange ◽  
Empirical Relationship ◽  
Flowing Water ◽  
Exchange Coefficient ◽  
Heat Exchange Coefficient ◽  
Hydro Power ◽  
Temperature Changes ◽  
Air Temperatures ◽  
The One ◽  
Semi Empirical

In order to be able to predict water temperatures in rivers which are to be harnessed for hydro power, it is essential to take into account the heat exchange with the atmosphere. It is often sufficient to predict average temperatures and temperature changes for periods of some days. A simple model for the heat exchange between flowing water and atmosphere has been developed for this purpose. The model offers a semi-empirical relationship between air temperature and water temperature. In this paper the model is applied to the Orkla river in Central Norway, and it is demonstrated how analyses of diurnal variations of water and air temperatures make it possible to predict the downstream decay of temperature changes originating from man-made releases. As a result an average heat exchange coefficient is calculated for Orkla for the summer of 1980. This calculation indicates that the cooling/heating rate in the flowing water in Orkla is considerably greater than the one for lakes under the same meteorological conditions.

Contralateral effects of thermal stimuli on manual performance capability

1963 ◽  
Vol 18 (4) ◽  
pp. 769-771 ◽  
Author(s):  
R. Ernest Clark ◽  
Charles F. Flaherty
Keyword(s):  
Surface Temperature ◽  
Normal Level ◽  
Manual Task ◽  
Surface Temperatures ◽  
Contralateral Hand ◽  
The Subject ◽  
Performance Capability ◽  
Manual Performance ◽  
Thermal Stimuli ◽  
Contralateral Effects

The performance capability of one hand was studied as a function of its surface temperature and that of the contralateral hand. Three findings were determined to be statistically reliable for the subject sample tested: a) when the performing hand itself was cooled to a surface temperature of 40 F, performance decrements appeared which were independent of the temperature of the contralateral hand; b) when the performing hand was kept warm, cooling of the nonperforming hand resulted in an average reduction of 33% in the time typically needed for the completion of the manual task; and c) the surface temperature of a hand not exposed to the cold was found to fall an average of 2 F below its normal level when the contralateral hand was cooled to surface temperatures of 55 F or lower. Submitted on August 20, 1962

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