A turbulence chamber (0.78 × 0.23 × 2.59 m3) consisting of ten small electric heater/blowers with an aluminum foil screen and three screens of 2-mm aluminum wire meshes can generate the nearly homogeneous isotropic turbulence within the 0.5 × 0.05 × 2-m3 region at the 0.11-m height of optical measurements. The temperature structure constant squared C2T = 52.9 K2 m-⅔ was obtained from the temperature structure function measurements measured by using a differential microthermocouple system. The refractive-index structure constant squared C2nat the 632.8-nm wavelength was calculated from C2T:C2n = 3.00 × 10-11m-⅔. The average wind velocity and temperature were 0.41 m/sec and 53°C, respectively. From the power spectrum of temperature fluctuations, the inner and outer scales of turbulence are determined: lo = 5.0 mm and L0 = 6.5 cm. The measured temperature structure function and power spectrum of temperature fluctuations satisfy the ⅔ and -5/3 power similarity laws in the inertial subrange, respectively.
© 1978 Optical Society of America
Hideya Gamo and Arun K. Majumdar, "Atmospheric turbulence chamber for optical transmission experiment: characterization by thermal method," Appl. Opt. 17, 3755-3762 (1978)