Three valve arrangement

Figure 19.1 Annular flow arrangement and devices to oscillate fuel flow AR — annular ring BS — backward-facing step FI — fuel injector ID — inner duct MD — main duct PT — pressure transducer SR — swirl register (all dimensions are in mm), (a) annular flow arrangement (6) needle valve arrangement to oscillate fuel flow 1 — vibrator, 2 — receiver, 3 — needle, 4 — spider (c) arrangement to deliver oscillated fuel to inner duct and (d) arrangement to oscillate fuel flow with three circumferentially equispaced injectors...

Design arrangements for reduced-temperature secondary systems (sometimes referred to as injection circuits) include fixed provisions for minimum dilution rates. Conventional system-balancing devices with three-port automatic modulating valves to regulate mixed water temperatures and, hence, heat output are used. Automatic safety controls must prevent excessive temperatures occurring in the coil circuits, as floor fabrics or finishes could be damaged very rapidly. 

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