Accession Number : ADP002295

Title :   Ground and Inflight Operational Effects of APU's (Auxiliary Power Unit's),

Corporate Author : VEREINIGTE FLUGTECHNISCHE WERKE G M B H BREMEN (GERMANY F R)

Personal Author(s) : Renken,J. H.

Report Date : SEP 1983

Pagination or Media Count : 17

Abstract : The Airbus APU has to deliver well defined quantities of bleed air and electrical power under two very different conditions: on-ground and inflight. This requirement may imply a compromise. The on-ground operation is essentially governed by problems such as noise-generation and -emission, or ingestion of hot gas which constrains the possible range of intake and exhaust positions. The flight operation is dominated by the external fuselage flow conditions the intake and exhaust are exposed to. These may significantly affect the installation pressure-ratio and, with that, the inflight restart envelope and inflight performance. Depending on fuselage surface pressures and boundary layer conditions, intake and exhaust-geometries and -ducting have to be designed so that a favorable IPR is provided during APU starting as well as APU-operation, at the same time keeping negative effects such as drag increase at a minimum. The effect of these environmental conditions on the APU-performance is discussed.

Descriptors :   *Power equipment, Jet transport aircraft, Onboard, Gas turbines, Power distribution, Inflight, Ground support, Exhaust systems, Air intakes, Boundary layer flow, Energy conversion, Bleed systems, Air, Electric power, Noise(Sound), Ingestion(Engines), Hot gases, Flow fields, Installation, Tails(Aircraft), Commercial aircraft, Auxiliary, Starting, West Germany

Distribution Statement : APPROVED FOR PUBLIC RELEASE