What is Difference Between Mass and Volume Flow

It depends on what you are trying to do or move but most common systems use volume flow for fluids and is calculated as CFPM [Cubic Feet Per Minute] that way you know how big to make your pipes and pumps.

Very often a certain amount of Mass of fluid needs to be moved in a certain amount of time so you would find out the Mass required then convert that to Cubic Feet of fluid for the correct amount of Mass then decide how fast you need to move it Per Minute.

I do not know what kind of new Engineer you are but all Mechanical Engineers learn this in Fluids Classes and Thermodynamics/Heat Transfer classes.

Thanks,I am an electrical engineer, Therer is a difference if I choose Mass instant volume in the measurement way

You're out of your depth, Mildred. What are you trying to measure, at what temperature and pressure, in what pipe size, and why? I've asked you this before and I am getting fed up doing it.

Hello.

I had work with both types of instruments (on Gas, Water and Steam), volume flow measure use in most case the vortex theory, you can use a mass flow meter and a vortex flow meter to measure the same thing, in most cases mass measure is more accurate but you have to take in mind the enviroment, the process behavior, like temperature, vibrations, etc.

so if your process is almost always stable, for example no much temperature variations, you can decide to use a vortex flow meter with no concern, but if you really see non constant variations you must have to buy with "compensate temperature"

in the end is just up to what you need or want to measure, for example you can measure steem flow with a mass flowmeter or with a preasure transmiter using a orifice plate.

just remember to use the instrument your process need, and, yeah take in mind price as well, as better the technology as high the price.

regards

Thanks for your information, It is so benfits for me .

Steam

Temparture :300

4 bar

Is that 300°C or 300°F?

Is that 4 bar gauge or 4 bar absolute?

At last!

Consider vortex shedding as a measurement technique. I'd pick up the phone now and start talking to flowmeter suppliers, Mildred, then I'm funny that way.

very simple mass is the weight based and volume is area based. every element with a unit mass will have the different volume .

commonly the mass flow is used .

The ranges of thermal mass flow meters for gases are specified in such units as l_n/min, sccm or m³_n/h. These units look like volumetric units, but in truth they are expressions of Mass Flow. For example,

Imagine you have a cylinder of 1 litre, which is closed by means of a moveable piston of negligible weight. This cylinder contains 1 litre of air at ambient pressure, approx. 1 bar. The weight of this volume of air at 0°C is 1.293 g, this is the mass. When we move the piston half way to the bottom of the cylinder, then the contained volume of air is only ½ litre, the pressure is approx. 2 bar, but the mass is unchanged, 1.293 g; nothing has been added, or left out.