D4.4 - Calibration-Free Volume Flow Measurement Principle Based on Thermal Time-of Flight (TTOF) for Gases, Liquids and Mixtures

Abstract

The use of mass and volume flow measurement techniques is essential in industries for process control purposes. Therefore, a novel flow measurement principle based on the Thermal Time-of-Flight (TToF) is applied with the methods of heat transfer including heat source and heat sinks. An appropriate flow meter is designed which can be deployed to any kind of fluid considering gases, liquids and mixtures. With this significant advantage the TToF flow meter is calibration-free. The presented investigation includes a discontinuous heat source associated with a minimum of two thermal sensors arranged downstream. The heat source is used to generate a signal code [dT/dt] by injection of local thermal pulses into the flow line. The thermal sensors detect the time-dependent thermal gradients in the fluid at different positions. Herewith, the measurement technique aims at the determination of the flow velocity by ToF, with the particular advantage of applying to measurements of any fluids with unknown properties. The volume flow is determined by integrating the flow profile.