An Improved Device for Calculating the Velocity of Flow and Rate of Discharge of Water or other Fluid in Pipes, Culverts and Channels.

摘要

6278. Essex, E. H. March 20. S l i d e-rules adapted for calculating the velocity of flow and rate of discharge, and in the case of gases the loss of pressure, of fluids in pipes, culverts, &c. comprise scales proportional to the logarithms of the following quantities : D, the square. root of the sine of the inclination of the pipe corresponding to various gradients ; E, the hydraulic mean depth corresponding, it may be, to the diameters of circular pipes, or to the diameter of the top arch of ovoid culverts ; F, certain constants with an arrow showing the one generally employed ; G, H, velocity of flow ; J, the areas corresponding to the diameters of the pipes ; and K1, the proportionate depth of flow with an arrow for a full pipe. The scales E, F and J, K1 are placed upon sliders B, C respectively, and the remaining scales on the stationary baseboard A. In use, the diameter on the scale E is set against the gradient on the scale D, and the velocity is read on the scale G against the constant on the scale F. The discharge is obtained by setting this velocity on the reduced scale H against the diameter on the scale J, and reading on the scale L against the depth on the scale K1. Alternatively, the device may be in disk form with the scales D, L on the rim, the scales E, J on revolving annular disks, and the scales G, H on stationary disks.