Example of digital flow meter MASS-VIEW in an application
2. Can I use the MASS-VIEW digital flow meter at sub-atmospheric pressure conditions?
To answer this question properly, it is actually required to start with a closer look at the physical properties of gases. In physics and engineering, mass flow rate is the mass of a substance which passes per unit of time. Considering a sub-atmospheric flow rate, you can imagine that the gas flow rate needs to be (significant) higher to transport a particular amount of gas (mass).
Since the MASS-VIEW series operate on the principle of direct thermal mass flow measurement, the combination of its structural design and the increased (volumetric) gas flow rate in sub-atmospheric conditions might have negative side-effects to ensure a proper measurement. Therefore, the measurement output cannot be guaranteed in sub-atmospheric conditions.
3. Will the accuracy of my instrument be affected by dust, humidity, or oil mist in the process gas?
Humid air for instance can be seen as a mixture of water and air and additionally to this, dust and oil might be present in the process gas. The physical properties of those mixtures will differ from those of dry and clean air. As from a technical point of view, this flow meter series is able to deal with the humidity as long as there is no condensation inside the flow channel. However, the inaccuracy of a thermal mass flow meter calibrated for dry air could increase when humid air is applied instead of dry air.
As for the oil and dust; potential clogging of a thermal mass flow instrument in general is just around the corner. However, the thru-flow nature of MASS-VIEW’s working principle from Bronkhorst is relatively insensitive to possible clogging in potentially polluted industrial gas applications. However, the insensitiveness does not mean that clogging is impossible. It is highly recommended to filter those process gases before it enters the mass flow meter.