A. Steinfeld et al., EXPERIMENTAL SETUP OF A LASER DIAGNOSTICS SYSTEM FOR A HIGH-TEMPERATURE SOLAR RECEIVER REACTOR, Journal of solar energy engineering, 116(4), 1994, pp. 206-211
A solar receiver/reactor has been designed specifically to study high-
temperature gas phase chemical reactions using a laser based metrology
. It is a cavity-type receiver, lined with stabilized ZrO2, and operat
ed at temperatures up to 2000 K. The gas temperature is measured in si
tu using the coherent anti-Stokes Raman spectroscopy (CARS) of N2. Opt
ical access for the CARS measurement is accomplished via two side wind
ows, each subtending a 118-mrad cone angle at the center of the cavity
, providing enough clearance for the input laser beams and the output
signal carrying the temperature information. Two endothermic processes
were used for the initial evaluation of this method: the NH3 dissocia
tion into N2 and H2, and the CO2-reforming of CH4 into synthesis gas.
The process flow was directly exposed to high solar fluxes in addition
to infrared radiation emitted by the hot reactor walls. The laser-bas
ed metrology performed satisfactorily in spite of the presence of the
intense radiation field. This paper describes in detail the technical
aspects of the experimental setup, presents examples of spectra and te
mperature measurements, and discusses practical problems encountered d
uring experimentation.