La Houille Blanche
Number 1, Janvier 1968
|Page(s)||37 - 44|
|Published online||23 March 2010|
Calcul de la formation de glace dans les conduites forcées
The calculation of ice formation in penstocks
Chargé de cours à l'Ecole Nationale Supérieure des Mines de Saint-Etienne; Chef du Département Recherches de la Société B.V.S.
A close penstock heat balance analysis allowing for the main heat energy elements makes a clean sweep of the old empirical formula involving the non-freezing of a penstock. The true picture is very much more complicated. According to  the basic heat energy elements are expressed by formula (1) to (10). The heat balances of the moving water and the ice-coated walls are given by formula (11) and (12) respectively, with the five following independent variables: r*, Oe, H, x, t Differentiating Oc from (12) with respect to x yields formula (13), and after replacing the physical constants by their values in the calorie-metre-degree Centigrade-metric ton-hour system, the final formula, (14), is obtained, which unfortunately cannot be integrated. Bogoslovsky  gives a sufficiently accurate graphical solution for industrial requirements, which has been confirmed experimentally in situ on several occasions ( and ). Table 1 enables this graphical solution to be applied very quickly. Figures 1 to 3 show a practical application of the method to a numerical example taken from industrial practice. Practical rules derived from long experience are given in condensed form in chapter V.
© Société Hydrotechnique de France, 1968