Experimental Stand for Very-Low-Velocity Gas Flow Generation.

This article presents an experimental stand for the generation of gas flows with very low velocities. The constant volume air flow was generated in the measurement area with the use of a Mariotte bottle and a water piston (water column in a tank). The air-flow velocity was determined from the change in the height of the water piston with time, which was measured via the difference between the pressure above the water surface and the pressure at the bottom of the water column.

A Semi-Empirical Approach to Gas Flow Velocity Measurement by Means of the Thermal Time-of-Flight Method.

This paper presents a method of measuring gas flow velocity based on the thermal time-of-flight method. The essence of the solution is an analysis of the time shift and the shape of voltage signals at the transmitter and at a temperature wave detector. The measurements used a probe composed of a wave transmitter and a detector, both in the form of thin tungsten wires.