Eastern Instruments - Solids Mass Flow and Air Flow Measurement Equipment

When measuring the flow of air or gas in a duct or pipe, accuracy is dependent on the type of device used to make the measurement, but is very dependent on the flow profile in the duct or pipe.  For example, if the flow in the duct or pipe is turbulent, many types of flow measurement devices will not even be able to measure the flow or have such an error you would be better off not having the measurement at all.  Here we will look further into turbulence and ways to minimize or eliminate it so that an accurate air flow measurement can be made. What is Turbulence? Turbulence can come in many forms, for example the flow could be spinning in the duct (cyclonic flow), or the flow could be going in the opposite direction than it is supposed to be going (reverse flow), or it can be off to one side or even angular (not parallel to the center-line of the duct or pipe).  When a flow sensor, averaging pitot tube, thermal mass sensor (thermal dispersion), venturi, or even an ori...

One question that I am asked about all the time is "Why would I need to have a flow straightener and/or flow conditioner to get a good air flow measurement?"  The answer to this questions always comes down to duct configuration or duct arrangement.  If you have a duct that is long and straight, then it is a good bet that there are enough "straight duct runs" to get a decent flow profile in the duct and therefore a good flow measurement.  What most customers find is that these long and straight duct runs just don't exist.  In fact, most customers find that there are more turns, twists, bends, tees, and transitions than the even knew they had. Air/Gas Flow Products & Technology So, how do you know if your flow is turbulent and does not have a good flow profile (i.e. has swirl, reverse flow, cyclonic flow, or flow that is all to one side of the duct)?  For most customers, one way is to go by some guidelines that have been established that give you the ...