Engineering topics

Lee, Robert

Publications and source records attributed to Lee, Robert.

3 records

NASA NTRS2006

Gas Turbine Engine Carbon Oil Seals Computerized Assembly

In a bearing compartment there are a series of parts when assembled determine the location of the bearing and seal as related to the centerline of rotation. We see part datums that do not establish A coincident path from the bearing to the seal. High engine vibration can cause severe oil leakage. The inability of the seal to respond fast enough to the rotating element Radial Seal: Sensitive to housing air pressure Sensitive to seal runout ? Axial Seal: Very sensitive to seal perpendicularity to shaft. Goals include: 1) Repeatable assembly process; 2) Accurate assembly process; 3) Minimize seal runout; 4) Design to engine centerline of rotation, i.e. bearings.

Lee, Robert↗

NASA NTRS1995

Buffered Telemetry Demodulator

Buffered telemetry demodulator (BTD) is radio receiver designed mainly for recovery of low-rate data binery phase-modulated onto square-wave subcarrier on sinusoidal or suppressed sinusoidal carrier signal and received at low symbol-to-noise ratio. In BTD, received signal not only processed in real time but also recorded and subsequently reprocessed to recover data otherwise lost. BTD could be implemented on general-purpose computer workstation.

Tsou, Haiping↗

NASA NTRS1995

Acoustically shielded exhaust system for high thrust jet engines

A flade exhaust nozzle for a high thrust jet engine is configured to form an acoustic shield around the core engine exhaust flowstream while supplementing engine thrust during all flight conditions, particularly during takeoff. The flade airflow is converted from an annular 360.degree. flowstream to an arcuate flowstream extending around the lower half of the core engine exhaust flowstream so as to suppress exhaust noise directed at the surrounding community.

Carey, John P.↗