Flat-plate design

Compare the thickness required for a 2 m diameter flat plate, designed to resist a uniform distributed load of 10 kN/m2, if the plate edge is ... 

Flat plates or concentric cylinders may be utilized in the construction of an ionization chamber. The flat plate design is preferred because it has a well-defined active volume and ensures that ions will not collect on the insulators and cause a distortion of the electric field. The concentric cylinder design does not have a well-defined active volume because of the variation in the electric field as the insulator is approached. Ionization chamber construction differs from the proportional counter (flat plates or concentric cylinders vice a cylinder and central electrode) to allow for the integration of pulses produced by the incident radiation. The proportional counter would require such exact control of the electric field between the electrodes that it would not be practical. 

A special stainless steel was developed in Australia and patented (Jaffray, 1999). Production costs and endurance of the resulting flat plate design (Foger etal, 2000) were improved relative to that of the firm s initial all-ceramic design. The bipolar plates and interconnects were stainless steel. The cell had operational difficulties, and has been discontinued. The firm has just established a UK division, to compete in Europe. 

Optical cells. Another desirable capability is to achieve elevated fluid pressures in an optical-cell. Simple flat-plate designs exist using silica or sapphire windows and 0-ring seals and have the potential of routinely achieving pressures to 100 MPa. A challenge would be to find ways of making these optical cells inexpensive and safe for use in the classroom. 

To achieve all of the benefits of the microchanneled, flat plate design, multiple membrane wafers must be stacked together to form multiwafer modules. 

Figure 1-3. Flat plate design for a fuel cell... 

Ion collectors at ambient pressure, however, do not require a cup design because the impinging ion on the collector does not have sufficient energy to produce secondary ions thus, the potential loss of secondary ions is not a problem for quantification. Under ambient pressure conditions, ions can be collected with a simple flat-plate design called a Faraday plate. Faraday plates can be easily interfaced to an IMS as a flat, terminal plate after the ion separator. 

Figure 8.7 Flat-plate design of SOFCs. (From Yamamoto, 2000, with permission from Elsevier.)...

FIGURE 23.31 Effect of temperature on capacity of traction batteries, typical flat-plate design. From Ref. 23.)... 

These factors change when comparing flat-plate to wound prismatic cell designs. As described below, many of the larger batteries utilize a flat-plate design whereas small cells almost universally utilize a wound design consistent with commercial cost requirements. 

The spiral-wound plate roll is mechanically structured to prevent interplate movement found in flat-plate design. 

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