Abstract: The invention relates to a system for the discharge and/or distribution of a gas from a source of the gas, and more specifically relates to such a system which enables gas from a source to be discharged and/or distributed to at least two gas-utilizing units irrespective of the operational status of each unit. The gas from the source is conducted from a manifold to each unit via respective conduits. Each conduit has a valve having a maximum closed position, in which the valve is open to a predetermined minimum degree exceeding zero, and a maximum opened position, in which it is open to a predetermined extent set by the maximum gas capacity of the respective unit. One valve maintains a gas flow delivery pressure to its respective unit not exceeding a selected maximum pressure. The other valve maintains a gas flow-rate corresponding to the gas-requirement of its respective unit.

Abstract: Non-contact heat exchangers comprise a gas carrying duct which has fluid carrying tubes inserted therein so that hot gas may heat the tube fluid. This simple principle is extrapolated into a heat recovery steam generator for a combined cycle power plant where hot gas turbine exhaust gases are used to heat steam turbine feed water in order to produce steam. A noise/vibration problem may be generated at certain gas turbine loads which create stimulus frequencies at or near boiler tube response frequencies. The invention proposes an optimum arrangement of upstream baffles which suppress the stimulus frequency generated by the gas flowing through the duct.