An interferometer for measuring gas density as a function of time during a transient flow is described. This is an absolute instrument capable of measuring density changes over an approximate range from 10−2 to 10−5 g/cm3. Since the instrument requires only small optical components, it is relatively simple and inexpensive to construct.
No takes yet. Share an insight, caveat, or question.
Curtis et al. (1954) studied this question.