Total heat generation

Flammability. PhenoHcs have inherently low flammabiHty and relatively low smoke generation. For this reason they are widely used in mass transit, tiinnel-building, and mining. Fiber glass-reinforced phenoHc composites are capable of attaining the 1990 U.S. Federal Aviation Administration (FAA) regulations for total heat release and peak heat release for aircraft interior facings (1,70). 

Note 2 Since no system can be heal adiabatic in practice there is a ce.rtain amount of heat dissipation from the impregnated windings to the stator core and housing. This heat dissipation is considered as 15% of the total heat generated as in lEC 60079-7. 

With normal interrupting devices the fault current would last for only a few cycles (maximum up to one or three seconds, depending upon the system design). This time is too short to allow heat dissipation from the conductor through radiation or convection. The total heat generated on a fault will thus be absorbed by the conductor itself. 

The basic idea of using TCR in a gas turbine is usually to extract more heat from the turbine exhaust gases rather than to reduce substantially the irreversibility of combustion through chemical recuperation of the fuel. One method of TCR involves an overall reaction between the fuel, say methane (CH4), and water vapour, usually produced in a heat recovery steam generator. The heat absorbed in the total process effectively increases... 

Economizers are heat transfer tube bundles that preheat MU water or FW flowing within the tubes by extracting waste heat from the flue gas during its exit path to the stack. They typically account for approximately 10% of the total boiler heat transfer surfaces, while absorbing only 7% of the total heat generated in the boiler system. 

Qr is the total heat generated by the reactions taking place, evaluated from the standard heats of reaction at 25°C (298 K). 

At present the Earth s temperature is not in thermal equilibrium, i.e., the net OLR is still not as high as generated net heat. Natural cold sinks in water, ground, and atmosphere slow down the effect of thermal pollution. The main sources of natural cold are in water and ice. The total volume of global water is 1.4 x 1018 m3, of which 94% is seawater while 3 x 1016 m3 (2%) of the water is ice in the form of glaciers and ice fields (Singh and Singh, 2001). 

The total heat flow (Q) at the film surface is equal to the mass flow rate (W k) times the heat of condensation (AH). That is, the heat generated by condensation at the surface must be equal to the heat transported away by conduction and radiation for steady state to be achieved. In mathematical terms this results in the equation. 

Usually, isothermal calorimeters are used to measure heat flow in batch and semi-batch reactions. They can also measure the total heat generated by the reaction. With careful design, the calorimeter can simulate process variables such as addition rate, agitation, distillation and reflux. They are particularly useful for measuring the accumulation of unreacted materials in semi-batch reactions. Reaction conditions can be selected to minimize such accumulations. 

Among the three heat-generation terms, the irreversible and reversible heat sources of ORR are dominant. For a straight-channel cell shown in Figure 12, the total amount of heat release is 2.57 W, of which the irreversible heat is 55.3%, the reversible heat 35.4%, and the Joule heat only 9.3% The total heat released from the fuel cell can also be estimated from the overall energy balance, i.e. 

It is usually assumed that the total heat released when one mole of ATP is hydrolysed is equal to the enthalpy change (-21 kJ) but this is only in vitro. It ignores the fact that hydrolysis of ATP in vivo demands simultaneous generation of ATP to maintain its concurrence, which requires aerobic metabolism, which also expends energy. When this is taken into account, the hydrolysis of one mole of ATP is actually responsible for release of 90 kJ of heat (calculated on the basis that oxidation of one mole of glucose generates 30 moles ATP). 

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