Abstract: | This paper presents results of an investigation of unsteady periodic heat-transfer, carried out on a special experimental facility.Notation ch
contact heat-transfer coefficient
- q, qst
specific and steady heat flux through the contact zone
- Pc
contact pressure
- , f, m
thermal conductivities of the materials of the contact pair, the thermally insulating film, and the intercontact medium
- re
reduced thermal conductivity
- t
strength limit of the material
- h1, h2
heights of contact-surface profile irregularities
- hf
thickness of the thermally insulating film
-
relative area of actual contact
-
contraction coefficient
- c/cy
duty factor (ratio of contact duration to working cycle duration)
- fcy/fo
relative frequency (ratio of contact cycle frequency to a fixed frequency)
-
a
thermal diffusivity
- tst
steady temperature at depth x from the contact surface
- k
order of harmonic
-
cyclic frequency
- Ac, Bc
Fourier series coefficients
- ka
amplifier gain
- yq
heat-flux coordinate on the oscillogram
- cs
constant stub
-
l
absolute distance of separation
-
intercontact gap at zero load
- b,
coefficients describing the surface roughness
-
relative separation of surfaces
-
thermocouple sensitivity
- r
specific electrical resistance
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 37, No. 5, pp. 898–904, November, 1979. |