Design and Validation of a Non-Invasive Thermal Flowmeter for Industrial Applications

Non-invasive flow meters are particularly suited for applications in the food and pharmaceutical industries, where their design must not only ensure precise measurements but also facilitate efficient decontamination of the flow channel. This article describes the design, manufacture and testing of an improved type of non-invasive flowmeter based on the principle of thermal measurement. The proposed flow meter achieves an accuracy of 1 % across an extended flow range of 10 to 180 kg/h. The device incorporates two resistance thermometers mounted externally to the flow channel, effectively eliminating interference with liquid flow while minimizing contamination risks. Key innovations involve the optimization of flow channel geometry, increasing the differential temperature to 50 °C, and adjusting the parameters of King’s law for higher measurement accuracy. Experimental testing demonstrates that the proposed device surpasses commercially available alternatives in both extended flow range coverage and measurement accuracy. This concept shows potential for the development of industrial flow measurement technologies, especially in applications requiring higher accuracy and extended operating ranges.