Power lost

The power lost just in driving the bipolar pass transistor is... 

The power dissipated at two different frequencies has been calculated for all reactions and compared with the energy loss to the walls. It is shown that at 65 MHz the fraction of power lost to the boundary decreases by a large amount compared to the situation at 13.56 MHz [224]. In contrast, the power dissipated by electron impact collision increases from nearly 47% to more than 71%, of which vibrational excitation increases by a factor of 2, dissociation increases by 45%, and ionization stays approximately the same, in agreement with the product of the ionization probability per electron, the electron density, and the ion flux, as shown before. The vibrational excitation energy thresholds (0.11 and 0.27 eV) are much smaller than the dissociation (8.3 eV) and ionization (13 eV) ones, and the vibrational excitation cross sections are large too. The reaction rate of processes with a low energy threshold therefore increases more than those with a high threshold. 

A Hcomb = net heat of combustion of the fuel W = power production Wposs = power lost due to mechanical inefficiencies... 

The brake power PB can be defined as the actual power delivered to the pump by the prime mover. It is the sum of liquid power and power lost due to friction and is given by the equation... 

Regional economics of TDF are paramount. Electric Power Research Institute (EFRI) created a computer model of TDF use in a cyclone-fired boiler. The model included an economic analysis of alternative fuel firings to account for the fact that, if boiler efficiency decreases, the company would need to purchase power to replace power lost by the boiler derating.12 These costs are called "busbar power costs".12 Even considering the decrease in the net heat rate caused by TDF use, the model found that TDF provided overall savings in levelized busbar power costs relative to 100 percent coal-firing.12... 

As an illustration, suppose the surface of water in a reservoir is 500 ft above the level of the site of a power plant and that there is available a flow of 200 ft3/s. In this case, H = z = 500 ft and P = 62.4 x 200 x 500 = 6,240,000 ft lb/s, or 11,340 hp, which is the total power available. If in the pipeline the friction loss is hf = 25 ft, then the power lost by friction is Whf and is seen to be 567 hp. Again, suppose a nozzle discharges 50 lb of water per second in a jet with a velocity of 120 ft/s H = V2/2g = 224 ft. Then the available power in the jet is 50 x 224/550 = 20.3 hp. The expression power equals force applied times velocity of the point of application of the force cannot be used in the preceding case, because it has no physical significance, as there is no force applied to anything, nor is there any point of application. In the case of a jet, the force it might exert would depend upon what happened when it struck an object, and the power produced would depend upon the velocity of the object. But the available power of the jet is a definite quantity, no matter what it acts upon or whether it ever acts upon anything. 

Power dissipation—In fluid motion, power lost due to frictional resistance and is equal to the power given by the agitator. 

Brake Horsepower.—The power lost in friction, f.hp., may be regarded as constant so that the brake horsepower, b.hp., is i.hp. — f.hp. at all loads. The mechanical efficiency at full load is... 

In a large system, power lost in transmission is dependent on factors such as the number of transformers, the length of the transmission lines, the size of the wires, the type and number of customers and the peak voltage used. The very best systems deliver less than 80% of their generator output to the customer and many deliver much less. 

Power lost to friction is likely to have a component proportional to for motion against a lubricated surface and a component proportional to for motion through fluids. 

The power lost in the steam turbine plant is less than the power consumed by the vapor compressor. Although the theoretical power W lost by the turbine exhausting at 22 psia instead of at 1.3 psia is exactly the same as the power consumed by a compressor taking the same amount of steam from 1.3 to 22 psia, the actual turbine efficiency of E drops the turbine power lost to WE and the compressor efficiency of raises the power consumed by the compressor to W/E. ... 

The energy stored cannot increase ad infinitum, so ultimately the power input to the cavity must equal the sum of the power dissipated resistively and lost by other mechanisms diffraction losses, coupling into the circuit etc. The power lost in the steady state is thus the input power Pin. 

For a reversible process, AS, and, therefore, To AS, and LW, are zero. For an irreversible process, AS. and L W are positive. The lost work represents the energy flow (power) lost because of irreversibilities in the process. The lost work is much easier to relate to than AS. ... 

In an industrial setting, electrical measurement of the power consumption is the simplest and most commonly utilized technique. A wattmeter can be used to determine the total power draw by the motor. This measurement includes the power lost... 

Fig. 2.13 The Thevenin equivalent circuit for a receiving antenna always yields the correct power delivered to the load impedance Zl. The power lost in the antenna impedance Za represents power scattered somewhere, not necessarily in the back direction. Additional scattering not accounted for by Za will in general take place.

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