On the Ball Flowmeter and the Ball Viscosimeter

摘要

In the report the hydrodynamic lubrication theory is used to determine the conditions of a ball in a tube filled with viscous liquid. In previous reports hydrodynamic lubrication has been studied under the usual assumptions of incompressible lubricant, constant viscosity, and laminar flow. Special consideration has been taken to the existence of cavitation regions. The problem of a ball in a tube is applicable in two different cases, namely the ball flowmeter, where the location of a ball in a conical tube gives the amount of flow, and the ball viscosimeter, where the velocity of a ball falling in a tube with constant diameter is used to determine the liquid viscosity. The study is made for the non-cavitating case, and small clearance between the ball and the tube is assumed. (Author)