Inlet systems high-speed

Monitoring should include the usual parameters worthy of surveillance in high-speed turbo machinery the temperature of journal bearings, vibration and axial position of the pinions, inlet and discharge temperatures combined with discharge pressure from the individual compressor stages, and various lube oil system devices. Competent manufacturers make sure all measurement locations are completely prewired on the machine and made available at predefined interfaces or in terminal boxes for connection at the plant site. 

Other Applications Very small, very low-flow, and relatively high-velocity exhaust inlets, similar to LVHV nozzles, have been used successfully to control fumes from electric soldering irons." " Some investigations have been made into small, point-control exhaust ventilation for aerosols generated by high-speed dental tools. However, such low-volume point-control ventilation systems have not seen widespread use. 

General texts on GC are numerous [118,119] narrow-bore GC was addressed by van Es [120]. Sample introduction techniques and GC inlet systems have been reviewed [25,90] and split/splitless [121] and on-column injection [122] were considered specifically. Stationary phases [123], multiple detection [103], derivatisation [124,125], and quantitative analysis in GC [109] have been described. High-speed GC has recently been reviewed [126]. For a compendium of GC terms and techniques, see Hinshaw [127]. 

Klemp, M., A. Peters, and R. Sacks, High-Speed GC Analysis of VOCs Sample Collection and Inlet Systems, Environ. Sci. Technol., 28, 369A-376A (1994). 

For steady-state analysis (i.e., no time variation) the coupled system is essentially elliptic, with some hyperbolic characteristics. The continuity equation alone is clearly hyperbolic, having only first-order derivatives. That is, it carries information about velocity from an inlet boundary, across a domain, to an outlet boundary. By itself, the continuity equation has no way to communicate information at the at the outlet boundary back into the domain. Based on the second-derivative viscous terms, the momentum equation is elliptic in velocity. However, because it is first order in pressure, there is also a hyperbolic character to the momentum equation. Moreover the convective terms have a hyperbolic character. There are situations, for example in high-speed flow, where the viscous terms diminish or even vanish in importance. As this happens, and the second-derivative terms become insignificant relative to the first-derivative terms, the systems changes characteristics to hyperbolic. 

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