Abstract: A heat exchanger positioned within an annular duct of a gas turbine engine is provided. The heat exchanger extends substantially continuously along the circumferential direction and defining a heat exchanger height equal to at least 10% of a duct height. An effective transmission loss (ETL) for the heat exchanger positioned within the annular duct is between 5 decibels and 1 decibels for an operating condition of the gas turbine engine. The heat exchanger includes a heat transfer section defining an acoustic length (Li), and wherein an Operational Acoustic Reduction Ratio (OARR) is greater than or equal to 0.75 to achieve the ETL at the operating condition.

Abstract: A combined circulation condenser for a steam cycle apparatus is disclosed. The steam cycle apparatus includes a steam generator with a port for receiving a fluid. The steam generator presents heat to the fluid to generate steam that is directed out another port, which presents the steam to a turbine to generate electrical power. The turbine has an outlet that directs an exhaust steam into a condenser. A fluid flow system is inside the condenser, which directs cooling water along a pathway through the condenser so that the cooling water cools the exhaust steam, forming condensate. A condensate pump collects and pumps the condensate along another pathway through the condenser so that the condensate can additionally cool the exhaust steam. Simultaneously, the exhaust steam warms the condensate. This pathway directs the condensate to a feed pump, which pumps the condensate back to the steam generator through the generator's input port.

Abstract: The method provides luthiers of fretted instrument with a novel approach for installing frets with increased accuracy. The method is an improvement in calculation of fret placement over the “Rule of 18” because it relies on the length of the vibrating string. This method is more pronounced at the end of the fret board closest to the bridge due to the angle formed by the string when depressed with respect to the axis of the fret board. With respect to the twelve-step octave, the scale length is multiplied by the constant of the twelfth root of 0.5 to calculate the length of the string from fret contact to saddle contact for the next tonal step.