Abstract

A distributed-feedback InGaAsP diode laser, emitting near 1.38 μm, was used to acquire spectrally resolved absorption profiles of H2O lines in the ν1 + ν3 band at a repetition rate of 10 kHz. The profiles were used for simultaneous measurements of flow parameters in high-speed, one-dimensional (1-D) transient flows generated in a shock tube. Velocity was determined from the Doppler shift, which was measured with a pair of profiles simultaneously acquired at different angles with respect to the flow direction. Temperature was determined from the intensity ratio of two adjacent lines. Pressure and density were found from the fractional absorption. From these primary gasdynamic variables, the mass and momentum fluxes were determined. Experiments were conducted with three different gas mixtures in the shock tube: pure H2O at initial pressures lower than 3 Torr, up to 6% of H2O in O2 at initial pressures below 120 Torr, and up to 8% of H2 in O2 at initial pressures below 35 Torr. In the third case, pyrolysis of H2/O2 behind incident shocks produced known yields of H2O. With all three mixtures, results compare well with 1-D shock calculations. This H2O diagnostic strategy shows promise for applications in both ground and flight testing.

© 1994 Optical Society of America

Full Article  |  PDF Article
OSA Recommended Articles
Continuous wave laser absorption techniques for gasdynamic measurements in supersonic flows

David F. Davidson, Albert Y. Chang, Michael D. DiRosa, and Ronald K. Hanson
Appl. Opt. 30(18) 2598-2608 (1991)

Rapid tuning cw laser technique for measurements of gas velocity, temperature, pressure, density, and mass flux using NO

Albert Y. Chang, Michael D. DiRosa, David F. Davidson, and Ronald K. Hanson
Appl. Opt. 30(21) 3011-3022 (1991)

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Figures (13)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Tables (2)

You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Equations (7)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Metrics

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription