INFLUENCE OF BACKGROUND VERTICAL MOTIONS
ON FREE CONVECTION OVER A THERMALLY
INHOMOGENEOUS HORIZONTAL SURFACE

L. Kh. Ingel'

UDC 532.517:534.2:551.558

In a linear approximation the problem of the influence 
of background vertical motions on free convection over a thermally 
inhomogeneous horizontal surface has been solved analytically. The 
dimensionless number that determines this influence and that represents 
the ratio of the product of the characteristic velocity of background 
vertical motions and of the horizontal scale of thermal inhomogeneities 
to the coefficient of thermal diffusivity of the medium has been found. 
Descending motions may effectively suppress convection (not only decrease 
the height of penetration of convective motions into the medium but 
also to decrease their amplitude substantially). Ascending motions 
increase the height of penetration of convective motions into the 
medium and, to a lesser extent, the vertical component of convective 
velocity.

"Taifun" Scientific-Industrial Association, 82 Lenin Ave., 
Obninsk, 249038, Russia; email: lingel@obninsk. com. Translated from 
Inzhenerno-Fizicheskii Zhurnal, Vol. 81, No. 1, pp. 97-101, January-February, 
2008. Original article submitted May 10, 2006.