What does the following sentence mean?

I think it can only be understood in this way: he was referring to measurement performance; changes in pressure density and the like do not cause any changes in measurement performance, but when the medium itself changes, the flow meter is powerless to deal with it.

What this means is that even though those parameters change, the flow meter can still function properly. However, the volume flow rate measured will certainly not be comparable to the values obtained before the conditions changed, as the reference points for comparison are different. Only by introducing temperature and pressure compensation and adjusting all measurement values to standard conditions or design conditions can they be made comparable. I’m not sure if my understanding is correct.

Chinese characters are profound and complex; could the original poster also include the two sentences that come before and after this one? Considering everything, it’s difficult to understand if only one of those sentences is quoted. Or perhaps the source of this sentence could be mentioned

This post was last edited by jizhenlin on 2016-11-25 at 10:27. PN=NRT; liquids are generally incompressible, so a premise should be added for measuring incompressible liquids

Vortex flow meter 1. Advantages: (1) The vortex flow meter has no moving parts; its measuring element has a simple structure, it offers reliable performance, and it has a long service life. (2) Vortex flow meters have a wide measurement range. The range ratio can generally reach 1:10. (3) The volumetric flow rate of a vortex flow meter is not affected by thermal parameters such as the temperature, pressure, density, or viscosity of the fluid being measured. Generally, no separate calibration is required. It can measure the flow rate of liquids, gases, or vapors. (4) It causes minimal pressure loss. (5) It has high accuracy, with a repeatability of 0.5%, and requires minimal maintenance.

Volumetric flow rate is primarily related to flow velocity and pipe diameter; changes in temperature and density have little impact on the measurement of volumetric flow rate, unlike mass flow rate.

This post was last edited by zxg.wylton on 2016-11-25 12:26. That’s correct. Let’s not complicate things: it is the measurement principles of these instruments that ensure that the aforementioned medium parameters do not affect the measurement of the volumetric flow rate of the actual fluid. It does not refer to mass flow rate or standard volumetric flow rate. Of course, whether the instrument can measure something and whether it performs well are separate issues; they depend on many factors such as the specific implementation method, installation, medium, technical approach, and so on. In short, achieving accurate, stable traffic measurement without the need for maintenance is actually quite complex. However, it shouldn’t be understood in an absolute sense; for example, does a change in temperature have no impact on the volumetric flow rate measurement of the physical substance? Vortex streets have an impact; when the temperature changes, the dimensions of the measuring section change, and as those dimensions change, the flow rate measured also changes.

Flow volume has nothing to do with these, lee

I think you’re right. Also, don’t differential pressure flow meters, such as orifice plates, lack this feature? I’ve never been able to figure it out.

When selecting a product, parameters such as medium temperature, pressure, density, and viscosity are taken into consideration, right?