MEMS Thermal Time-of-Flight Flow Meter
Abstract
Thermal time-of-flight (TOF) technology has been considered to be one of the most effective approaches that could provide an accurate flow measurement at ultra low flow speed. While the technology remains on paper for over half a century without real implementation, the lack of market drive may be one of the major reasons. Current demands in energy management such as city natural gas metering, medical applications for respiratory machines and others have revitalized this technology. Thermal TOF technology in principle can provide accurate flow speed measurements for gases regardless of its gas compositions. However, traditional design of TOF sensors is often very vulnerable to fluidic conditions, in particular, moisture, particles and other contaminations. In this paper, we present a thermal TOF gas flow meter that is equipped with a robust MEMS thermal TOF sensor which can be used in fluid where moisture and particles exist. The design and fabrication of the MEMS TOF sensor are described followed by its circuit scheme. The design of the flow meter and the test results are presented.
Event details
- Event
- tc9-2010