Accession Number : AD0764851

Title :   AVRG: A PDP 8/I Data Acquisition and Averaging Program for Synchronous Hot Wire Measurements.

Descriptive Note : Research rept.,

Corporate Author : NAVAL ACADEMY ANNAPOLIS MD MICHELSON PHYSICAL LAB

Personal Author(s) : Elder,Samuel A.

Report Date : 31 MAY 1973

Pagination or Media Count : 27

Abstract : The program, in function-modified FOCAL, is specifically designed to enable measurements to be performed on oscillating vertical velocity profiles in the mouth of a flow-excited cavity resonator. Simultaneous hot wire and pressure microphone data samples are recorded at an exact multiple (20X) of the oscillation frequency so as to obtain a synchronous record of the cyclic variation of longitudinal stream velocity at many points in the mouth region. Data is atuomatically averaged over 100-cycle intervals to remove turbulent background variation. From the stored data, either two or three dimensional velocity profile information can be reconstructed, using sound pressure at the base of the cavity as a phase reference. Options are provided for Fourier analysis, real time (oscilloscope) display, and TTY printout. (Author)

Descriptors :   (*CAVITY RESONATORS, DATA PROCESSING), (*COMPUTER PROGRAMS, INSTRUCTION MANUALS), SOUND TRANSMISSION, VELOCITY, WIND TUNNELS, FOURIER ANALYSIS

Subject Categories : Computer Programming and Software
      Test Facilities, Equipment and Methods
      Acoustics
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE