ABSTRACT
This chapter introduces the reader to some of the more common measurement methods unique to combustion environments which address the problem areas of more usual fluid mechanics measurements. Measurements in combustion, however, present many unique problems. Of interest in combustion are temperature, velocity, composition and pressure, both time average and instantaneous values. The measurements of interest will make use of many properties of gas molecules which belong to the subject of modem physics. The laser has revolutionized combustion research in providing a non-intrusive and non-perturbing device for measurement of many quantities of interest. A typical laser used for velocity measurements is the Argonion laser, which gives beams of several wavelengths in the visible part of the light spectrum. A relatively simple, but limited, method for measurement of either particle loading density in a gas or simply gas density in the absence of particles is through Rayleigh scattering.
