Primary flow elements
The recoverable pressure drop should be recovered by 6 pipe diameters downstream of the cone meter. According to Eq. The permitted diameter of the carrier ring is given in 5. Static pressure of fluid upstream of venturi tube at the cross-section of the pressure tap, [Pa].
Botros et al. The data are shown in Fig! International Organization for Standard- ization, Geneva. It is interesting that similar data are obtained with each pair odf tappings and that the shift is approximately proportional to the fraction of the pipe which is rough.
In practice this is a minimum requirement. The model was first published in and became ISO later. The diameter ratio can be calculated to? To be consistent with ISO a protruding weld should not cause a change in measured diameter greater than 0.
ORIFICE PLATE , WORKING PRINCIPLE AND ORIFICE EFFECT
In a flow metering device based on the Bernoulli Equation the downstream pressure after an obstruction will be lower than the upstream pressure before. To understand orifice, nozzle and venturi meters it is necessary to explore the Bernoulli Equation. Assuming uniform velocity profiles in the upstream and downstream flow - the Continuity Equation can be expressed as. For a given geometry A , the flow rate can be determined by measuring the pressure difference p 1 - p 2. The discharge coefficient c d is a function of the jet size - or orifice opening - the. The viscous effect is usually expressed in terms of the non-dimensional parameter Reynolds Number - Re. Due to the Benoulli and the Continuity Equation the velocity of the fluid will be at it's highest and the pressure at the lowest in " Vena Contracta ".
Since all the computational and most of the experimental data in Fig. ISO ISO a Fluid flow in closed conduits-Connections for pressure signal transmissions between primary and secondary elements. Appendix 2! Calculates the diameter ratio beta used to characterize a wedge flow meter as given in  and .
Log In Sign Up. However, and in practice a single tapping on the side or on the top is common. Research Project NX We don't save this data.