# Flowmeters

## Flowmeters

• Submitted By: ranitvnit
• Date Submitted: 06/10/2010 10:23 AM
• Category: Science
• Words: 1355
• Page: 6
• Views: 243

NAME: Suraj Khurana
EN. NO. : BT08CHE022
TITLE: ASSIGNMENT ON FLOW METERS

Sr. no. | Types | Mechanism | Applications |
1. | Differential Pressure Flow meters1.orifice plate2. venturi tube3. nozzles4. variable area rota meter | 1. Orifice plate : With an orifice plate, the fluid flow is measured through the difference in pressure from the upstream side to the downstream side of a partially obstructed pipe. The plate obstructing the flow offers a precisely measured obstruction that narrows the pipe and forces the flowing fluid to constrict. 2. 3. Venturi tube : In the Venturi Tube the fluid flow rate is measured by reducing the cross sectional flow area in the flow path, generating a pressure difference 4.      5. where A1 and A2 are the cross-sectional areas of the venturi meter at its throat and inlet respectively 6. where and are the piezometric pressure heads respectively 7. V2= velocity at throat   8. Nozzles : When a gas accelerate through a nozzle, the velocity increase and the pressure and the gas density decrease. The maximum velocity is achieved at the throat, the minimum area, where it breaks Mach 1 or sonic. At this point it's not possible to increase the flow by lowering the downstream pressure. The flow is choked. 9. Q=KP⌃0.5 10. Q= flow in L/min through the nozzle 11. K=nozzle k factor 12. P= total pressure in bar at flow rate Q 1. Calculate the value of discharge coefficient for the orifice meter Variable area rota meters: The rota meter consists of a vertically oriented glass (or plastic) tube with a larger end at the top, and a metering float which is free to move within the tube. Fluid flow causes the float to rise in the tube as the upward pressure differential and buoyancy of the fluid overcome the effect of gravity. 2. Formula for rota meter q"=q√p1-p/p1-1pq”= standard liquid flowq= standard water flow...