Pressure, temperature, and density measurements using high-resolution N2 cars

M. A. Woodmansee, J. P. Kuehner, R. P. Lucht, J. C. Dutton

Research output: Contribution to conferencePaperpeer-review


Mean pressure, temperature, and density measurements have been made in a gas cell and along the centerline of an underexpanded jet using highresolution N2 CARS. This method takes advantage of the line-broadening effects and population shifts of the rotational structure in the nitrogen (u = 0 → 1) Q-branch which are pressure- and temperature-sensitive. Experimental CARS spectra were acquired with high spectral resolution, Δω = 0.16-0.18cm-1. Theoretical spectra, created by a N2 spectral modeling program, were fit to the experimental spectra in a least-squares manner. Temperature and pressure were determined as adjustable parameters in the least-squares fit and density was then determined through an equation-of state. For gas cell pressures between 1 and 5 arm, the pressure values extracted from the CARS spectra exhibited an approximately 0.15 atm bias above the transducer pressures, probably because of Raman saturation effects. However, in the underexpanded jet measurements, our Stokes laser power was lower and agreement between measured and predicted pressures and temperatures along the jet centerline was excellent. The potential of performing pressure and temperature measurements on single laser shots was also examined.

Original languageEnglish (US)
StatePublished - 1998
Externally publishedYes
Event34th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, 1998 - Cleveland, United States
Duration: Jul 13 1998Jul 15 1998


Other34th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, 1998
Country/TerritoryUnited States

ASJC Scopus subject areas

  • Energy Engineering and Power Technology
  • Electrical and Electronic Engineering
  • Mechanical Engineering
  • Control and Systems Engineering
  • Aerospace Engineering


Dive into the research topics of 'Pressure, temperature, and density measurements using high-resolution N2 cars'. Together they form a unique fingerprint.

Cite this