TEMPERATURE PULSATIONS IN A VISCOUS SUBLAYER
The results of measuring statistical characteristics of temperature pulsations over the range of Re-numbers from 104 to 6·104 at a non-isothermal turbulent flow of water in a rectangular plain chamber are given. Heating was performed through a 10 mm thick copper plate by a heater made of 0.1 mm thick stainless steel pasted onto a textolite support.
The averaged and pulsation velocity and temperature fields have been obtained, as well as pulsation momenta up to the fourth order in magnitude. It has been shown that at Pr = 7 and Re = (1÷6)·104 the intensity of temperature pulsations achieves its maximum at Y+ = 6÷9. At heat transfer through a thick copper wall within a thermal sublayer the relation between RMS temperature pulsations and local temperature drop as well as the distribution of spectral pulsation density remain constant. With a low-inertial wall the high-frequency temperature pulsation components in a viscous sublayer damp with an approach to wall.