On the Ascending Velocity of the Pilot Balloon in Open Air

Abstract

In this paper the author applied the well known functional form for fluid resistance, that is on the determinationof a new formula for the ascending velocity of the pilot balloon in the open field. As an observational material for the determination of the numerical values of the constants in the formula we took the results of observation of the balloon ascent in open air at the Aerological Observatory at Tateno. Thus we obtained as the new formula, in which the velocity of balloon ascent U is expressed in metres per minute, the lift L and the buoyancy Q are in grams.
The calculated values of U by the new formula show better coincidence with the observed ones than those by the formula of Tateno, of the Signal Corps of U.S.A., and of Dines.
The numerical value of n obtained is 0.3293. This means that the ascending velocity of the pilot balloon varies as ρ^-0.0681, where ρ is the density of the surrounding air. The smallness of the index of ρ is the second strong point of the new formula.