What is the approximate pressure loss when fluid flows through a throttling device?
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What is the approximate pressure loss when fluid flows through a throttling device?
This post was last edited by ylb913 on 2015-11-12 at 11:09. I checked several orifice plates; the normal differential pressure at full scale ranges from 25 kPa to 60 kPa, as well as 40 kPa, 16 kPa, 10 kPa, and 6 kPa. Of course, the actual pressure drop is less than this maximum measurable differential pressure.
This requires analysis on a case-by-case basis; in some cases the pressure drop is high, but the impact on indicators such as energy consumption is minimal, for example when the pipeline itself needs valves to regulate flow rate or when the pressure difference resulting from the direction of the fluid flow is already very large. In some cases, the pressure drop is low, but the energy consumption loss is high, such as in applications with high flow rates. As the sofa mentioned, throttle element pressure drop and pressure loss are two different concepts. What the original poster is concerned about is pressure loss
The pressure loss associated with the flow of fluid through a throttling element varies depending on the shape of that element; it increases as the value of β decreases. This loss can be approximated by the following formula: Pressure loss δP = (1 – αβ²)ΔP / (1 + αβ²), where α is the flow coefficient； β —— diameter ratio of the throttle element ； ΔP —— Differential pressure. For orifice plates, since the flow coefficient is generally between 0.6 and 0.8, when β varies within the range of 0.2 to 0.8, the pressure loss is approximately (95%–34%) ΔP.
Throttling elements include everything that serves to throttle flow, even a section of pipe. Not limited to orifice plates only
This post was last edited by HEJIYUER on 2016-1-17 00:19. Here’s the simplest estimate for you. Permanent pressure drop/differential pressure range = 1－β1.9 @jiaguoyun
Approximately 0 to 200 kPa, higher values are not excluded