Analytical and experimental studies have been carried out on the behavior of strong shock tube diaphragms. These diaphragms exhibit large moments of resistance to opening due to stresses at the hinge line of the diaphragm petal. High speed shadowgraph photographs of the detailed opening process have been obtained and have been shown to compare well with the analytical model derived for flowfield-diaphragm interaction. A nondimensional resistance parameter is shown to control the behavior of the thick diaphragm and the detailed flow process which controls the opening is identified.

The vertical velocity field of a natural convection plume arising from a horizontal line heat source was investigated experimentally in detail. The measured vertical velocities were found to be 20–25 percent less than that predicted by analysis. Various causative factors for the discrepancy between analytical and experimental results were investigated, and shown to have a minimal effect. The power law relationship between the plume vertical velocity and energy input to the line source was found to be substantially greater than that predicted by analysis. A normalized similarity function did provide an excellent representation of the lateral diffusion of energy and momentum in the plume, indicating the validity of the boundary layer approximation for the velocity field. It was postulated that further refinement of the stream functions defined by existing analyses is required to accommodate the effects of the upstream flow field that exists in the physical representation of a line source and is omitted from consideration in the development of the analyses.

Electron density and temperature measurement method by using emission spectroscopy in atmospheric pressure nonequilibrium nitrogen plasmas Phys. Plasmas 13, 093501 (2006); 10.1063/1.2338282Crystal size and temperature measurements in nanostructured silicon using Raman spectroscopy A comparison of temperature measurement of oxygen in the 0-0 and 0-1 rotational bands using laser Raman spectroscopy Rev. Sci. Instrum. 45, 1580 (1974);The rotational temperatures at pressures near 1 atm have been successfully measured in pure nitrogen. The precision available, even with unsophisticated instruments, is adequate to allow local temperatures to be measured in a flowing gas with virtually no disturbance of the flowfield. Using a double monochromator and including the flowfield within the laser cavity would increase the signal and decrease scattered light.

The modification of a commercial laser for intracavity molecular scattering experiments is discussed. An improvement of almost 100 times in laser intensity is reported. Steps taken to eliminate an undesired secondary laser line produced by the laser because of the increase of laser intensity are presented.