The development of radiotracer methods for laminar flow measurements in small channels—II. The tracer-sphere method

Abstract

A method is developed which utilizes entrained rigid radioactive spheres to measure laminar volumetric flow rate and channel volume. The tracer-sphere velocity is shown to be simply related to the undisturbed average channel velocity. A detector response moments method is used to measure the tracer-sphere velocities. A dual tracer-sphere technique is proposed to determine both the channel velocity and radius by measuring the velocities of two tracer spheres of different radii. Feasibility experiments indicate flow rate measurements are accurate to within 3% for this method.