Can a velocity-type flow meter combined with a densitometer achieve the effects of a mass flow meter?

Of course, it’s possible to calculate the current density of the medium through temperature and pressure compensation, and from that determine the mass flow rate. In production, vortex flow meters or orifice plate flow meters are generally used for measuring steam flow. Through pressure stabilization and compensation, the density of the medium in the pipeline at that moment can be determined, from which the mass can be calculated. Because in both buying and selling, the price is determined by quality

Thank you for the advice. What about solutions? The concentration of a solution can only be maintained within a certain range in terms of manufacturing processes. Can this method still achieve the same results as those of a mass flow meter?

Of course, that’s also possible. Regardless of the concentration, the volume flow rate and density can be measured using instruments; by multiplying these values together, the mass flow rate is obtained.

By the same logic, it’s possible……

This post was last edited by QQ3503226090 on 2016-6-24 at 11:36. There is an issue here that needs to be clarified: on the surface, volume × density = mass, but the question is how to ensure that the “density” in question is indeed the density of that specific volume. Therefore, if the medium is relatively uniform, the densitometer needs to be installed on the pipeline to ensure that density and volume are synchronized; this can achieve an effect similar to that of a mass flow meter (more or less – it would be best to have real-time density multiplied by real-time volume) ； If the medium is not uniform, determining how to average this density becomes an issue. If it’s possible to use real-time density multiplied by real-time volume, then this problem does not arise; otherwise, it can lead to significant errors. In short, the key to the problem is real-time density × real-time volume, and the densitometer and volume meter should be as close to each other as possible (to purely solve this problem) ； Furthermore, its accuracy certainly cannot match that of a mass flow meter; that goes without saying. Different opinions are welcome for discussion.

In other words, if the densitometer is installed in a location such as a liquid storage tank, it will be unable to detect changes in the density of the medium during transportation, which will still lead to errors. Therefore, it is more appropriate to install it in a pipe near the flow meter, right?

The explanation on the 6th floor is very clear: if it is to be used for measurement, this approach is absolutely unacceptable

If your company has storage tanks, it’s a good idea to use a decent handheld density meter for measurement. The density of gasoline and diesel varies across different layers within the storage tanks; in such cases, which density should you use?； The temperature of the material inside the pipeline is also different from the temperature inside the tank; a difference of over 10° is quite normal. Such a temperature difference results in a significant variation in density. Therefore, it is unreasonable to use the real-time density of the storage tank along with the real-time volume indicated by the volume meter ； A better solution is the V20 handover, but there is still fitting error. I hope this can provide some ideas to help you solve the problem. As for exactly how to do it, you’ll need to weigh the options or conduct experiments; there will be right and wrong approaches.

As for the claim that liquids are incompressible, it depends on how large your allowable error is.

It has strong performance in terms of power delivery (it was later acquired by Emerson and integrated into HighSense). Thermo Fisher Scientific, Anton Paar, and Lemis are all specialized manufacturers of densitometers; you can consult them. The precision of the first three companies can reach 0.1 kg/m^3. Ask them for their advice on where it should be installed.