Maximum power output

Lasing substances Physical state Laser wavelength (nm) Pulse length or continuous wave Typical maximum power output (watts)... 

Unlike the aircraft turbiae, the ground-based gas turbiae operates continuously at the same power setting, usually 60—80% of maximum power output except when starting. Air and fuel flow patterns are constant and the combustor can be tuned to minimise smoke formation and high metal temperatures. 

It is important that atmospheric conditions at the installation site be specified, since engines operate with veiy little excess combustion air and consequently maximum power output is proportional to air density. 

Diesel engines, however, operate on an unrestricted air flow at all speeds and loads to provide the cylinders with an excess air charge. This results in a very lean air/fuel ratio of approximately 90 1 to 100 1 or higher at an idle speed. At the engine s rated speed (full load maximum power output) the air/fucl ratio will drop to 20 1 to 25 1 but still provide an excess air factor here of 10 to 20 percent. This excess air supply lowers the average specific heat of the cylinder gases, which in turn increases the indicated work obtained... 

Maximum Power Output (WM) and Open-Circuit Voltage (Voc) for SOFCs with Doped-Ceria Electrolytes... 

However, there seems to be some disagreements on the exact influence of anode composition on the cell/anode bulk resistance. While Kawada et al. [42] indicated that cell bulk resistance also reached minimum when the Ni content was 40 vol% (Figure 2.12), Koide et al. [25] showed that as the Ni content increased, cell bulk resistance decreased continuously, and cell maximum power output also increased (Figure 2.13). 

For example, the required lower bulk electrical resistance and surface contact resistance are directly related to reducing internal power consumption in fuel cells to achieve maximum power output. The requirements of high flexural strength and flexibility (ultimate strain) are important to assure no distortion of fluid fields and no crack in a plate sustained in the large compressive loading when each unit cell is assembled together as a stack. This is particularly important when the thickness of the plate becomes thinner and thinner (can be close to or less than 1 mm [9]) and the dimension of the fluid field becomes smaller and smaller. Whether it is elastic or plastic, the large... 

As intensity increases, the contributions of blood glucose and glycogen to ATP generation increase. Above about 50% of maximum power output, the rate of glycogen utilisation increases almost exponentially since some glycogen is converted to lactic acid at an increasing rate. 

Figure 13.20 The use of glycogen and/or fatty acids during a prolonged running event (an ultramarathon). The distance of an ultramarathon is usually >50 miles. In the early part of the run, both glycogen and fatty acids are the fuels oxidised by the muscle. After several hours, glycogen is exhausted and fatty acids are the only fuel used. As fatty acid oxidation cannot provide more than about 60% of the ATP required for maximum power output, if the athlete is running at about 70 or 80% of the maximum, the output (i.e. the pace) must slow. Hence the rate of oxygen consumption (VO2) falls to about 60% of maximum (V02 ax), as shown in the Figure. The data on which the plot is based are from Davies Thompson (1979).

Determine the maximum power output of the cycle. Find the heat-transfer added, heat transfer removed, heat transfer surface area of the low-temperature side heat exchanger between the heat engine and the heat sink, and efficiency of the cycle at the maximum power output condition. 

Referring to Problem 1 and with fixed heat source and heat sink temperatures, determine the maximum power output of the cycle. Find the working fluid temperatures in the isothermal heat addition and heat... 

Each photoelectrode was retested after mounting and current voltage plots obtained. All photoelectrodes decreased in performance and one became essentially inoperative. This is attributed to excessive handling during mounting which resulted in abrasion and deterioration of the deposit. The maximum power output of the individual mounted electrodes in the assembly varied from 5.TO mW to 0.13 mW. The maximum power obtained from the assembled converter was 27 mW. Under short circuit conditions the maximum power at 90.2 mA and 100 mV was 9 0 mW. The light intensity incident at the photocell was 92.5 mW/cm. ... 

Specific Heat Release Rate. To utilize many combustion systems most effectively, the maximum power output is to be obtained for the smallest possible size and weight. As a result, the physical size of the combustion chamber as well as all other components should be held to a minimum. This requirement specifies that the specific heat release should be as high as possible. This quantity, usually expressed in energy units per unit volume, unit time, and unit pressure squared, is a measure of the ability to heat the gases used in the thermodynamic cycle. Some idea of the orders of magnitude of prevailing heat releases in combustion equipment can be obtained from the values in Table II. 

In order to get an estimate of the solar-to-electrical conversion efficiency on layered compounds, sample D has been measured in sunlight. The result, obtained at 92.5mW/cm2 insolation is shown in Fig. 8. The maximum power point is at 0.33V and 10.7mA/cm2, with a resulting solar conversion efficiency of 3.7%. As is evident from Fig. 7, some samples show better overall performance than sample D. The best of these, sample G, the surface of which was accidentally damaged before being measured in the sun, had a maximum power output which exceeded that of sample D by a factor of 1.4 bringing the estimated solar conversion efficiency to 5.2%. 

Curzon, F.L. Ahlborn, B. Efficiency of a Camot engine at maximum power output. Am.. Phys. 1975, 43, 22. 

To investigate these findings further the authors determined heating rates of the employed multimode instruments and the Discover unit, once again using toluene as solvent. After 10 min irradiation at a constant maximum power output for each microwave reactor, different final temperatures were measured (Fig. 17). Furthermore, it could be shown that the observed differences in temperature are not only related to the different heating efficiencies of the instruments but also to the specific vessel material [27]. Usually the vessel material itself is not completely microwave-transparent and therefore it is at least partially responsible for heating of the irradiated solvent via conventional thermal conduction [42]. 

Fill factor — The current versus potential I(U) characteristics of a —> power source, contrarily to those of power dissipation devices, is not limited to the first and third quadrant. In this case the I(U) curve crosses the U and I axes at values different from zero. The value of I at U = 0 is denoted -+ short-circuit current, Jsc, and the value of U at I = 0 is denoted open-circuit potential, Uoc. The maximum power output, Pmax> from a power source depends on the shape of the I(U) curve and is given by Tmax = ( 7) max> excluding first and third quadrant points. The fill factor FF is given by FF = yfff-... 

In summary, the apparatus comprised a conventional (domestic) microwave oven with a maximum power output of 1.2 kW (1). The reactor (2) was a fused silica crucible placed in a moulded microwave-transparent insulating brick (3) that was suspended from the... 

In some earlier life tests performed by Wilson and co-workers, PEFCs utilizing thin-film platinum catalyst layers typically experienced a gradual performance loss over the first 500 to 1000 h of operation and then stabilized at about 70% of the original performance (here, performance is described in terms of the current density measured at 0.50 V, i.e., close to the maximum power output of the cell). In such life tests. 

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