Out-of-plane micro triple-hot-wire anemometer based on Pyrex bubble for airflow sensing

Abstract

The paper reports novel design and fabrication of out-of-plane micro airflow sensors based on the hot-wire sensing principle, i.e. gas cooling of electrically-heated wires. Three micro Ti/Au/Cu hot-wire resistors have been fabricated on an out-of-plane Pyrex bubble with height of 300 µm. They are arranged 120 degrees apart on the sidewall of a bubble at height of 100 µm for airflow velocity and direction detection. Air velocity around the out-of-plane bubble structure has been investigated for square and circular package designs. The sensor with axisymmetric circular package has demonstrated the ability to detect velocity (<10 m/s) and to determine flow direction with an error less than ±8° when the velocity is 10m/s. The sensitivity could be further improved in a new design with increased bubble height (1 mm) and elevated hot-wire resistor position (500 µm), according to the modeling results.

Ammunition Reliability Against the Harsh Environments During the Launch of an Electromagnetic Gun: A Review

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Application of Low-Cost Sensors for Building Monitoring: A Systematic Literature Review

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Micro anemometer by a MEMS compatible lab-on-a-tube technology

“…The work [3] has obtained high sensitivity for airflow speed and direction detection by using three manually-assembled MEMS hot-film resistors arranged 120 degrees apart on a cylindrical substrate. To improve the assembly effectiveness, we have also proposed three self-assembled micro hot-film resistors on a borosilicate glass bubble [4]. In order to elevate the thermal resistors to a higher position on an axisymmetric cylindrical structure, this paper presents a novel micro anemometer with three hot-film resistors on a glass tube surface, which will be completed in a programmable UV lithography system with multi-layer alignment by our developed MEMS compatible lab-on-a-tube technology.…”