Dm. Mceligot et al., NATURAL-CONVECTION BETWEEN A VERTICAL CYLINDER AND A SURROUNDING ARRAY, Nuclear Engineering and Design, 146(1-3), 1994, pp. 267-276
The generic situation considered is natural convection between a singl
e heated, vertical cylinder and a surrounding array of cooler vertical
cylinders in a triangular pattern. The ratio of the test section temp
erature to the cooling tube temperature was varied up to 2.6 by adjust
ing the electrical power. The Rayleigh number, based on test section d
iameter and air properties evaluated at cooling tube temperature, rang
ed from 2.9 X 10(4) to 4.6 X 10(5). Results indicate that the convecti
ve heat transfer data could be approximated as Nu(D)(T(ts)/T(ct))0.14
= 0.156 Ra(D)1/3 in the apparent turbulent region for Ra(L) > 1.2 X 10
(11).