1 / 11

FLOW MEASUREMENT DEVICES

FLOW MEASUREMENT DEVICES. ORIFICEMETER. ORIFICE-PLATE. ORIFICEMETER. INTRODUCTION. It consists of flat circular plate which has a circular hole, in concentric with the pipe. This is called orifice.

inigo
Download Presentation

FLOW MEASUREMENT DEVICES

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. FLOW MEASUREMENT DEVICES

  2. ORIFICEMETER

  3. ORIFICE-PLATE

  4. ORIFICEMETER

  5. INTRODUCTION • It consists of flat circular plate which has a circular hole, in concentric with the pipe. This is called orifice. • The diameter of orifice is generally 0.5 times the diameter of the pipe (D), although it may vary from 0.4 to 0.8 times the pipe diameter.

  6. Vena- Contracta The maximum contraction takes place at a section slightly on the downstream side of the orifice. Such a section is known as Vena- Contracta.

  7. ORIFICEMETER • Reduction of cross-section of the flowing stream in passing through orifice increases the velocity head at the expense of pressure head • Reduction of pressure between taps is measured using manometer • Formation of Vena- contracta- Fluid stream separates from the downstream side of the orifice plate and forms a free-flowing jet in the downstream side. • Orifice coefficient, generally, is 0.61

  8. ADVANTAGES • Low initial cost • Ease of installation and replacement • Requires less space

  9. DISADVANTAGES • More pressure loss • Low value of Coefficient of discharge • Susceptible to inaccuracies resulting from erosion, corrosion etc. • Tends to clog so not suitable for slurries

  10. FACTORS AFFECTING LOCATION OF VENA CONTRACTA • Reynolds number • Area ratio b/w orifice and pipe • Roughness of pipe

  11. FACTORS AFFECTING DISCHARGE COEFFICIENT • Type of orifice • Ratio of orifice diameter to pipe diameter • Reynolds number • Location of pressure connections

More Related