This manual will show how to measure flow in tubes with throat devices. The environment can be everything from industrial plants to laboratories. The performance of the flow measurement can be as good as 0.7 % uncertainty of actual flow from 10 to 100% flow if - Design - Manufacturing - Installation in tube - Instrumentation - Calculation of the flow is done according to the Matematica approach. The Matematica approach gives You full control over every parameter that have an impact on Your flow measurement. Over 20 parameters, like physical properties of the fluid, pipe roughness,...
At the first FLOMEKO in 1978, in Groningen, the Netherlands, the author with his NBS co-authors and his UK counterparts presented results from the first known international flow standards comparison using a tandem flow meter transfer standard. This comparison included a testing procedure designed to produce two, statistically independent flow meter calibration results that are “typical” of the lab’s normal calibration capability. As such, these results comply with the requirements for the Youden graphical analysis of variance to make conclusions regarding the comparability of the flow...
Headers commonly used in multirun meter stations can generate a variety of flow profile distortions influencing the measurement error of orifice meters. The experiments conducted at the low pressure air test facility at NOVA Research & Technology Centre covered a range of header configurations used in various meter station designs. The upstream piping configuration included a straight inflow pipe, a single elbow and two elbows in perpendicular planes in two orientations. It was found that some changes in flow configuration through the header and meter runs, as well as modifications to the...
According to the International Standard ISO 9951 all gas turbine flow meters should have a maximum permissible relative error of ± 1% over the higher flow range (from 0.2 Q max to Q max ), in the lower flow range ( Q min to 0.2 Q min ) the maximum permissible relative error is ± 2%. Usually the linearity of k factors, in percent, is used to express the basic relative error of a gas turbine meter. That means in the higher flow range the gas turbine meters shall have maximum permissible linearity of ± 1%, and in the lower flow range the gas turbine meters shall have maximum permissible...
In 1962, five leading Dutch process industries (BPM now Shell, Algemene Kunstzijde Unie now AKZO, DSM, Hoogovens now Corus and Unilever) got together to explore combining tests and sharing the results on process instrumentation. Companies were at the time carrying out these activities individually at very high costs. The five concluded that sharing instrument evaluation reports, even with direct competitors, would be to the benefit of all. A follow-up meeting held on the 16th December 1963 resulted in the formation of a co -operation panel under the Dutch name "Werkgroup voor Instrument...
This paper presents the results of the application of an ultrasonic gas flow meter in combination with a flow conditioner. This development aims at both reducing measurement uncertainty and the possibility of realising compact (short) metering runs, requiring less investment in piping and installation while maintaining good accuracy. For this purpose a package of a four-path ultrasonic gas flow meter with inlet pipe section and a modified Spearman (NEL) design flow conditioner placed at 3D upstream of the meter was found to be a good combination for reducing variability in the flow profile....
The basic principle of a rotary gas meter consists of two rotors in the form of a figure -8 that rotate inside each other with the precision of a gear wheel. The outer edges of these rotors turn in a very close fitting measurement chamber. The outer edges of the turning rotors transfer fixed quantities of gas from the inlet to the outlet like small buckets. Because the radii of the sealed streams in the middle between the two rotors always vary there is a discontinuous volume of gas passing per angle revolution of the rotors. The shape of variation is near a sinus and the frequency is four...
National metrology institutes around the world have embarked on an effort to compare their primary gas flow standards under the supervision of the Comité International des Poids et Mesures and its Working Group on Fluid Flow. As the pilot laboratory for the key comparison of low-pressure gas flows below 1500 L/min (CCM.FF-K6), NIST is designing the transfer standard package with the assistance and advice of the other participants. A number of topics are studied as part of the transfer standard design process. An analysis of the flow ranges and types of primary standards used by the possible...
Commercial vortex flowmeters use the well-known effect of Karman vortex street. The frequency of vortices generated in the wake of a bluff body is proportional to the average flow velocity. Usually it is detected by pressure sensors which are not very sensitive. Therefore bluff bodies of big sizes are required. An alternative method to detect the vortices in the streaming fluid is to use a high sensitive ultrasonic wave which is complex modulated. The demodulation can be executed by digital signal processing. Small sizes of bluff bodies can be realized. The bluff body size and the carrier...
Process Gas Chromatographs have been in use in the natural gas industry since the early eighties. The core analytical elements are commonly manufactured with conventional fine-mechanical tools. Recently MEMS technology has opened the doors to a new level of performance for on-line natural gas analysis.