Abstract
It is important to know a head loss of the flow in a concentric double pipe such as a reaction type flowmeter and a chemical reaction tube. The present study gives its experimental data using various types of concentric double pipes, in particular, giving the attention to the loss of total head through a turning-flow region from the outlet of the inner pipe to the inlet of the annulus between the inner and the outer pipes. They are given in terms of a non-dimensional clearance length (ξ=0.125〜50.0) between the outlet of the inner pipe and the bottom of the outer pipe for various values of area ratio (m=1.05〜∞) and Reynolds number (Re=4.2×10^3〜3.5×10^4). It is clarified that the effect of the clearance length upon the loss coefficient is classified into the three groups in proportion to the variation of m, namely, m≦1.54, 1.88≦m≦2.26 and m≧3.74 respectively.
