Determination of the Temperature Rise and the Maximum Safe Current through Multiconductor Electric Cables

1946 ◽  
Vol 17 (4) ◽  
pp. 255-262 ◽  
Author(s):  
Haig P. Iskenderian ◽  
William J. Horvath
Keyword(s):  
Temperature Rise ◽  
Electric Cables

scholarly journals SANDWICH PANELS – BEHAVIOR IN FIRE BASED ON FIRE RESISTANCE TESTS

2016 ◽  
Author(s):  
Paweł Roszkowski ◽  
Paweł Sulik
Keyword(s):  
Thermal Insulation ◽  
Fire Resistance ◽  
Temperature Rise ◽  
Sandwich Panel ◽  
Sandwich Panels ◽  
And Behavior ◽  
In Fire ◽  
Resistance Tests ◽  
Building Elements

<p>Sandwich panel is the material that is easy and quickly to install. Basing on a great experience in the area of determination of the fire resistance class of construction building elements the authors describe the properties and behavior of building elements made of the sandwich panels exposed to fire. The article presents the results of fire resistance tests carried out in accordance with EN 1364-1 non-bearing walls made of sandwich panels with use of different cores.</p>The following parameters were analyzed: temperature rise on unexposed side (I – thermal insulation), integrity (E) depending on the orientations and on the width of the sandwich panels, deflection depending on the thickness of the boards. Conclusions were made on the base of the analysis from fire resistance tests.

Numerical Verification of the Thermodynamic Determination of the Hydraulic Efficiency of Radial Fans

2019 ◽  
Author(s):  
Philipp Epple ◽  
Manuel Fritsche ◽  
Felix Reinker ◽  
Stefan aus der Wiesche
Keyword(s):  
Temperature Rise ◽  
Pressure Rise ◽  
Inlet Temperature ◽  
Numerical Verification ◽  
Hydraulic Efficiency ◽  
Hydraulic Power ◽  
The Real ◽  
Shaft Power ◽  
Real Temperature

Abstract For fans without cooling it is possible to determine the hydraulic efficiency measuring the pressure and the temperature rise through the fan. The shaft work can be determined according applying the first law of thermodynamics for an open system. Without any losses the change of state would be isotropic and the work done equal to the specific heat at constant pressure of the fluid times the isentropic temperature rise in the impeller. Due to the losses, however, the real temperature at the exit of the impeller will be higher than the isentropic temperature since the real process is polytropic. The isentropic temperature at the exit of the impeller can be computed by the isentropic relations with the inlet temperature and the pressure rise. The hydraulic efficiency can be computed as the ratio of the isentropic temperature rise divided by the real temperature rise. In order to verify this thermodynamic approach for the determination of the hydraulic efficiency CFD simulations of a radial fan were performed. In the CFD simulation the hydraulic power, the shaft power, the pressure rise and the temperature rise can be read out and computed directly. In such a way the hydraulic efficiency computed by the ratio of the hydraulic power by the shaft power can be compared by the thermodynamically computed efficiency. In this work this comparison has been performed and the results and the precision of the thermodynamically predicted efficiency are presented and discussed in detail.

Heats of Reaction of the System Rubber-Sulfur

1935 ◽  
Vol 8 (3) ◽  
pp. 456-469
Author(s):  
Archibald T. McPherson ◽  
Norman Bekkedahl
Keyword(s):  
Temperature Rise ◽  
Entire Range ◽  
Sulfur Compounds ◽  
The Other ◽  
Vulcanized Rubber ◽  
Heat Effects ◽  
Heats Of Reaction ◽  
Heats Of Combustion ◽  
Relative Measurements

Abstract PREVIOUS investigators have employed two methods for determining the heat effects when rubber is vulcanized. In one method the heats of vulcanization are found by subtracting the heats of combustion of vulcanized rubber—sulfur compounds from the heats of combustion of the corresponding mixtures of rubber and sulfur before vulcanization (1, 10, 11). This method is limited in precision by reason of the fact that the differences thus obtained are at most only a few per cent of the measured heath of combustion. The other method, which has been used previously, involves the determination of the temperature rise which occurs when mixtures of rubber and sulfur are vulcanized. This method has, for the most part, been used for relative measurements, but Blake (2) has recently employed it for quantitative determinations of the heats of reaction of rubber with proportions of sulfur up to about 8 per cent by weight. Recently Daynes (7) has employed a similar method for measurements over a wider range of composition. This investigation was undertaken for the purpose of measuring the heath of reaction of rubber with different percentages of sulfur over the entire range of composition in which combination takes place. The study was exploratory in character, the aim being to make the measurements by direct means with emphasis on simplicity rather than refinement of calorimetric procedure.

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