Calibration of a temperature dissipation probe in decaying grid turbulence

A four cold-wire probe, which allows all three components of the temperature dissipation rate epsilon(theta) to be measured, is "calibrated" in decaying grid turbulence, where (epsilon(theta)), the mean value of epsilon(theta), can be determined accurately from the decay of the temperature variance (theta(2)). Th, probe yields values of the three components of (epsilon(theta)) which are in reasonable agreement with local isotropy, in the range x(1)/M less than or equal to 50. The pdfs and spectra of the three temperature derivatives also satisfy local isotropy reasonably well.