Structural integrity pressure-temperature operating

For higher temperature operation, a polybenzimid-azole-based polymer electrolyte may be preferred. The PEMFC structures have good mechanical integrity under compression and expansion from differential temperature and pressure gradients that occur during operation. This system has minimal materials problems, except for the cost and operation characteristics of the membrane. The PEMFC operates at 1 A/cm at 0.7 V. The electrode reactions in acidic media have been discussed above. 

The structural integrity of the full-scale unit was checked in the same test rig that was used for heat transfer tests on the small-scale core. The unit was wrapped with Fiberglas and aluminum foil insulation and was operated for 75 min. During this time the flow rates, inlet temperatures, and inlet pressures were recorded. Although the outlet temperatures were not measured, a dramatic illus-... 

The SNPP will be pressurized to [Reserved] times the maximum operating pressure at [Reserved] temperature using inert gas to check for structural integrity and leak tightness. 

Preliminary accident analysis of MHTGR-IGT has been carried out by using THERMDC code. The results of the analysis indicates, under rating operation condition, the maximum temperature of fuel elements is about 980. In case of the depressurization with core heat-up, the fuel maximum temperature is 1477 . In case of the accident of loss of heat sink, the fuel maximum temperature is only lOSOt. It should be emphasized that, due to the integrated structure of the primary loop, the probability of losing primary operation pressure will be greatly reduced. 

Foams were proved to be highly suitable as catalytic carrier when low pressure drop is mandatory. In comparison to monoliths, they allow radial mixing of the fluid combined with enhanced heat transfer properties because of the solid continuous phase of the foam structure. Catalytic foams are successfully used for partial oxidation of hydrocarbons, catalytic combustion, and removal of soot from diesel engines [14]. The integration of foam catalysts in combination with microstructured devices was reported by Yu et al. [15]. The authors used metal foams as catalyst support for a microstructured methanol reformer and studied the influence of the foam material on the catalytic selectivity and activity. Moritz et al. [16] constructed a ceramic MSR with an inserted SiC-foam. The electric conductive material can be used as internal heating elements and allows a very rapid heating up to temperatures of 800-1000°C. In addition, heat conductivity of metal or SiC foams avoids axial and radial temperature profiles facilitating isothermal reactor operation. 

Tables 7-10 present excess pressure values that are limits for the assured integrity of building structures. However, the ALS may lose its function of a safety barrier at a lower excess pressure due to opening of safety valves in the leaktight compartments, whereupon a radioactive release may occur at upper elevations of the reactor budding. The leaktight compartments and the air space of the PSP may suffer overpressure during a LOCA with failure of the PSP cooling system (loss of ultimate heat sink), when steam condensation in the pool water is less effective at water temperatures exceeding about 85°C. Therefore, either the maximum permissible water temperature (for example <85°C) or the operating pressure difference of the safety valves may be adopted as an acceptance criterion for the PSP.

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