Presented by: Ayesha Nawaz (M13-CE-35)

ROTA METER

Objective to be achieved regarding rotameter : Construction

Working principle

Applications

Table of Contents:DefinitionConstructionTypes of tubesTypes of floatsOperating principleMeasurementEquation of flow rateGraphDistinguishing FeaturesApplicationsLimitationsClosing

Rota meter:“A device used to measure flow rates of fluids in a closed system”

Construction:•Tapered tube•Float

Tapered tube may be made of:Glass (for quick reading)

Metal (for corrosive conditions)

Plastic (for low cost)

DIFFERENT TYPES OF FLOATS:

Operating Principle:•When fluid is entered into the tube, some of the fluid strikes the float & some passes by.•Ultimately, float moves upward untilBeyonce force = weight of the floatAt this point, float will stop to move upward, float position will indicate flow rate!•Annular space increasing upward thus givingMore area , more flow, more upward movement of float & hence more flow rate!

HOW TO MEASURE FLOW RATE?

Equation for flow rate:CD= co-efficient of dischargeG= Flow rateg= gravitational accelerationP= density of the fluidPf= density of the material of the floatVf= volume of the floatAf= maximum cross sectional area of the floatA1= cross sectional area of the tubeA2= area of the annulus space

Graph between CD & Re No.

Distinguishing Features:• Variable area meter• Used for small flow rates• Tmax = 400○C• Pmax = 4MPa• Low installation cost & investment cost• No external power is required• Cost Effective

Applications:•Food industry•Fermentation•Paper industry•Oil & gas industry•Chemical industry

Limitations:Can’t be placed horizontal without amendments

Only for transparent fluids otherwise use magnet

Only for measuring small flow rates

Can’t bear very high temperatures & pressures without amendments

Video:

Conclusion:For measuring small flow rates like in laboratoriesWhen low cost is requiredWhen temperatures & pressures are not very highEasy to installReliableNo fuel/power consumption

References:Chemical Engineering by Coulson & Richardson, Volume 1Mechanical Variables Measurement By John G.Webster Flow meters & Flow measurements By P.Chattopadhay http://www.tech-faq.com/rotameter.htmlhttp://www.slideshare.net/search/slideshow?searchfrom=heade

r&q=rota+meterhttp://slideplayer.com/slide/2493605/

Questions/Answers session:

THANK YOU!