1. Process Variables and Sensors

2. Parts and materials needed for today (instructor will provide): DP transmitters Thermocouples Filled-bulb temperature sensor RTDs Heat source (e.g. cigarette lighter) Vortex flowmeter Thermal flowmeter Magnetic flowtube Turbine flowmeter Orifice plates Coriolis flowmeter Multimeters

3. Process Variables and Sensors Documents you will need for today: “Realistic Instrumentation Diagrams” worksheet (from the Socratic Instrumentation project website)

4. Fundamental Principles Brainstorm all the fundamental principles of physics you can recall that are relevant to the sensing of process variables such as pressure, level, temperature, and flow!

5. Pressure Measurement

9. Level Measurement

14. Temperature Measurement

15. Temperature Measurement: filled-bulb sensor

16. Temperature Measurement: RTD

17. Temperature Measurement: thermocouple

18. Flow Measurement: orifice

21. Flow Measurement: vortex

22. Flow Measurement: magnetic

23. Magnetic Flow Meters n Process must be a liquid n Minimum conductivity n Meter must be full

24. Magnetic Flowmeters MAGNETIC ADVANTAGES No Moving Parts Very Wide Rangeability Ideal For Slurries Unobstructed Flow Path DISADVANTAGES Liquid Must Be Conductive Physical Pressure and Temperature Limits

25. Magnetic Flowmeters n No moving parts n No pressure drop n Flowrate independent of viscosity, temperature, and density n Minimum upstream piping requirements n Electronics interchangeable without regard to size n Measure dirty liquids with solids n Measure highly corrosive fluids n Very large turndown n Linear output Advantages Over Other Technologies

26. Vortex Meter

27. Principle of Operation Q = V x A

28. Vortex

29. ADVANTAGES No Moving Parts For Liquid, Gas, or Steam Uneffected by Pressure, Temperature, or Density Changes. Wide Rangeability DISADVANTAGES Span Limitations Due to Viscosity Flow Profile Sensitive (Vortex) VORTEX / SWIRLMETER

30. Turbine Meter Principle of Operation Rotor velocity is proportional to fluid velocity

31. Turbine Meter n High accuracy (.5% of rate) n High rangeability (up to 50:1) n Compact design n Fast response time n Broad range of sizes n Clean water applications only n NIST Traceable Factory Calibration n Low cost, Easy to install n In and out of line, under pressure

32. Turbine Meter n Straight pipe run requirements n Process fluid lubricity n Reynolds number constraints ä Viscosity ä Density n Maintenance & recalibration Performance Considerations

33. Turbine Flowmeters TURBINE ADVANTAGES High Accuracy Suitable for Extreme Temperatures and Pressures Can Be Used On Gas or Liquid DISADVANTAGES Only For Low Viscosities Moving Parts Sensitive to Flow Profile

34. Flow Measurement: turbine

35. Flow Measurement: ultrasonic

36. Ultrasonic Flowmeters n Doppler n Time of flight Types

37. Doppler Flowmeter Ultrasonic Flowmeters Principle of Operation

38. Transit-Time Flowmeter

39. Ultrasonic Flowmeters n Reynolds number constraints n Entrained gas or particles for doppler n Clean liquids for time of flight n Installed without process shut down n Straight upstream piping requirements Performance Considerations

40. Flow Measurement: true mass

41. Application: distillation process

42. Extra: hydrostatic level sensor calculation