The influence of parameter deviate phenomenon of v cone flowmeter
Author:vacorda Source:vacorda.com Date: 2016-12-07 15:42:44
Outflow coefficient of v cone flowmeter is related to the diameter ratio of β and Reynolds number and other parameters, while it is sometimes difficult to ensure that the site parameters have been within the scope of the standard at the scene , therefore, when these parameters occur the deviate phenomenon, it will produce additional uncertainty. The following words give you the main influence of v-cone flow meter deviation from the standard parameters.
（Principle of v cone flowmeter）
1. The influence of β values
First of all, the value of β is the ratio between throttling diameter and the diameter of the pipe. After all, v cone flowmeter is derived from a circular orifice and classic Venturi tube. So v cone flowmeter also combines the advantages of their ability to measure the dirty medium and small pressure loss. According to the classic venturi theory, the actual β should be controlled within 0.75, when the β value is greater than 0.75 due to improper design, the efflux coefficient dispersion is too large, increase the uncertainty of the outflow coefficient.
(V cone flow meter)
2. The effect of Reynolds number
V cone flowmeter due to its special structure, and compared with the standard throttle device, the Reynolds number lower limit value has been greatly improved, but not very limited. When the Reynolds number is reduced unconditionally, the outflow coefficient of the v-cone flowmeter decreases as the Reynolds number decreases, and the uncertainty increases.
As a new differential pressure flow meter, the use of v cone flowmeter increased year by year in recent years, and even has the trends to replace the standard throttle device. However, it also has the limit for application of the high pressure occasion, because the structure of cone negative pressure tube will occur falling off phenomenon under the high pressure situation. So we can not make the blind production of v cone flow meter, and we must comply with the site parameters.