Laser for Open Channel Flow Metering

Transcription

1 Laser for Open Channel Flow Metering Pump Station Flow Monitoring Presented by: Glenn Hummel

2 Presentation Objective Keep your Toolbox equipped with Flow Metering Solutions Introduce a New Technology for Open Channel Flow Measurement Review a Time Tested Approach for Pump Station Flow Monitoring

3 Outline Overview of Open Channel Flow Measurement (OCM) Technologies Intro Latest Technology for OCM Review Pump Station Flow Monitoring

4 Open Channel Flow Measurement (OCM) Empirical Formula Manning Equation Primary Device Flumes & Weirs and Eq s Both used Level Sensors: Floats, Bubblers, Pressure Transducers - all Contacting Ultrasonic (Non-Contacting) Area Velocity Velocity & Depth Sensors Better Accuracy Portable, Easy to Deploy

5 Continuous Wave Doppler (CWD) [the economical workhorse]

6 Pulsed Doppler (PD) [higher accuracy, perf, & reliability at higher cost]

7 Contact Sensors The drawbacks of Contacting Sensor technologies are: Reliability Blinding (loss of reading) Silting (accuracy uncertainty) Failure (damage / exposure) Maintenance / Cleaning (cost) Small pipes (feasibility) Sensor caused obstruction in flow Debris, hydraulic issues

8 These drawbacks associated with contacting sensors have driven technology to provide Non-Contacting measurement solutions

9 Non-Contact vs Contact Why? Maintenance Blinding, Silting, Debris Far fewer visits required by non-contacting solutions Frequency & Costs (~$500 per site visit) Safety Cannot get flushed down a sewer pipe if you are not in the sewer. Large Pipe Difficult Installations Flow Depths greater than 3 ft Velocity over 3ft/second (tough for CWD) (equip wash-out) Small pipes <24 Low level flow measurement Shallow water depths with high velocities Confined Space Entry for Maintenance Permits / Traffic Control / Manpower

10 Non-Contact Radar Very Intelligent approach. Sensor above the sewage. Non-contact Level Measurement (Ultrasonic) Non-contact Surface Velocity Measurement (Radar) Advantages Minimal maintenance Above water installation Low level flow measurement Limitations Single Point, Surface Velocity Measurement does not yield velocity measurement representative of cross section Dead band in ultrasonic level measurement Required velocity profiling Only read velocity at the surface!

11 Area Velocity Contacting Meters Continuous Wave Doppler (CWD) Pulsed Doppler (PD) Non-Contact Meters Radar Laser Latest Advancement in Velocity Measurement Technology

12 LaserFlow TM

13 Introducing Isco s Non-Contact Solution LaserFlow Non Contact Laser Velocity measurement Non Contact Ultrasonic Level Measurement

14 Basic Operation Sketch Velocity Measurement f = 2 V cosθ / λ V = λ * f / (2 cosθ) where: f = Doppler frequency shift V = Water velocity θ = 45 degrees λ = Laser wavelength Return Doppler Signal Light Laser Flow Sensor Original Laser Light, λ = 635 nm 45 Degree Angle θ Below Surface V Flowing Water Stream 14

15 Single Point Velocity Method Ultrasonic Level Measurement Laser Velocity Measurement

16 Theory of Operation Below the surface Return Doppler Signal Light 5000 Spectral Velocity Readings

17

18 Off-axis reflected energy is weak and misdirected.

19 On-axis reflected energy is directed back to the sensor. However, the unfocused energy is very weak.

20 On-axis and focused reflected energy is directed back to the sensor with much intensity.

21 The frequency shift between the transmitted indicates the flow direction. The magnitude of the shift indicates the velocity.

22 Ultrasonic Level Sensor Range 0 10 feet 45 Deflector Plate 10 Beam Angle Virtual Zero Dead band 0-10 ft Ultrasonic dead band is exceeded by the time the signal reaches the bottom of the LaserFlow.

23 Design Concept Peak to average relationship Peak velocity is typically below the surface of the water at lower depths Moves away from the water surface at higher depths Turbidity and TSS Total Suspended Solids Minimum 15 PPM Balance 1/2 to 6 Below the surface in typical raw wastewater applications

24 Laser Velocity Measurement Ultrasonic Level Measurement Single Point Velocity Method Single point Velocity Method

25 Laser Velocity Measurement Ultrasonic Level Measurement Multidepth Velocity Method Multidepth Velocity Method

26 Laser Velocity Measurement Ultrasonic Level Measurement Multipoint Velocity Method Multipoint Velocity Method

27 Laser Velocity Measurement Ultrasonic Level Measurement Multipoint Multidepth Velocity Method Multipoint -Multidepth Velocity Method

28 When do you use single point velocity measurement? Uniform and consistent flow Battery Life is a concern Rapid Data Rate 1 minute

29 When do you use Multipoint velocity measurement? Non-Uniform Flow AC Power Longer Reading intervals

30 Submerged Condition Measurement during Submerged condition TIENet TM CW area velocity sensor Proven technology Not a point velocity measurement More accurate during surcharged conditions Measurement can start on different conditions Variable Rate Data Storage Laser Level Laser Velocity Laser Temperature CW Level CW Velocity Laser cone design prevents water from reaching the laser window

31 Submerged Condition Measurement TIENet TM Area velocity sensor connected to LaserFlow sensor Single cable from LaserFlow sensor

32 Normal Operation Laser velocity Ultrasonic Level (USLS)

33 Submerged Condition Begins

34 LaserFlow Fully Submerged CWD sensor reading velocity Pressure Sensor reading depth

35 Redundant Measurement TIENet Area Velocity sensor with a longer Cable 1,10, 23M A r ea V eloci t y (laser) L e v el (USLS) A r ea V eloci t y ( s o u n d w a v e) L e v el (p r essu r e t r ansdu c er)

36 Teledyne Proposed Solution Electronics

37 Level range accuracy Product Specifications 0.02 ft at 1 ft level change or less Velocity range +/-15 ft/sec Minimum depth for velocity 0.5 Focus range of Laser below the surface at 15 NTU /PPM Turbidity / TSS range 15-1,000 NTU/PPM Operating temperature Up to 140 F Battery 15 minute readings with single point, unidirectional setup 12 Weeks

38 Product Specifications Housing Materials Corrosion resistant ABS plastic IP 68 Anodized aluminum Stainless steel hardware Ultrasonic Sensor Kynar (corrosion resistant)

39 Installation Requirements Laser can be installed facing in the upstream or downstream pipe. Center the bracket over the flow stream.

40 Installation Requirements Install the LaserFlow sensor in the middle of the pipe, parallel to the water surface. Use the Laser On function to see where the beam hits.

41 Permanent Mount

42 Permanent Mount Wall mount bracket Vertical adjustment X axis adjustment or roll

43 Permanent Wall Mount Street Level Installation Tool Street level installation alignment tabs

44 Level installation

45 Locking handle

46 Max length 23 ft Street Level Tool

47 Facing into the flow

48 Facing away from the flow

49 Temporary application Spreader bar

50 Stability of Mounting hardware

51 How well does LaserFlow Technology Perform? Examples of Actual Performance Accuracy Repeatability

52 Single Point Velocity Method Within 0.5%

53 Omaha LaserFlow vs ADFM Difference = 0.36%

54 SAWPA comparison vs. OCSD reference Magmeter

55 LaserFlow Applications Collection System Monitoring Billing Inflow and Infiltration WWTP Permit Reporting: Raw Influent Final Effluent In plant pipes and channels Hydraulic Modeling Highly Accurate & Reliable Data Sets Industrial Discharge monitoring Harsh Chemicals and/or Environments Storm water Large debris

56 Summary LaserFlow Advanced Laser Velocity Measurement Multipoint Subsurface Velocity Measurement The only non-contact flow measurement system that reads below the surface Both precise and accurate Easy to install and maintain Excellent Submerged flow measurement option Flexible Platforms 2100 (Portable Battery Operated) Signature (Permanent Process Meter)

57 Oh, by the way did you know? CWD, PD, and LaserFlow sensors can be used to measure and log Water Temperature? Help indicate source or distinguish between inflow or infiltration Some sensors can provide continuous logging of velocity reading quality indicators.

58 Lift Station Monitoring 4501

59 Application Any application where fixed speed pumps are moving fluid from point A to point B. & Where the pumps are activated when specific volume thresholds are met in the source!

60 Purpose and Applications for Lift Station Monitoring Wastewater collection system studies Dry and wet weather flow conditions Inflow and infiltration studies (I&I) Capacity monitoring Future planning Billing measurement Lift station performance studies Proactive maintenance programs

61 Lift Station Monitor Operation Benefits: Accurately measure within 1% Influent flow Pumping rates for each pump Volume processed by the station Diagnose Abnormal pump station performance Maintenance issues Power issues

62 Lift Station Meter Setup Station information. Wet well volumes calculated using Wet well dimensions Pump operation levels Minimum requirement!!! Rated pump capacity Pump draw down test data Single pump operation Combination pump operation Station meter programming methods Volume method Rated pump capacity alone Rated pump capacity used when the station parameters cannot be obtained Pump capacity not learned nor updated fixed! Not as accurate!

63 Principle of Operation Wet well fills and empties Monitors pump ON / OFF intervals OFF = FILL ON = EMPTY The volume and time intervals are used Algorithms applied to calculate Flow into and out of lift station Pumping rate of each pump

64 3 methods of calculation 1 - Extrapolation Method Calculation method in the 4501.

65 3 methods of calculation 2 - Averaging Method

66 3 methods of calculation 3 - Trending Method Method used by the PC software Pumplink uses the 5 preceding events and the 5 following events to calculate and determine trend

67 Summary Report

68 Monthly Report

69 Daily Report

70 Event Report

71 Lift Station Monitoring Recap Collection system studies Dry weather analysis Wet weather analysis System planning/modeling Station monitoring Maintenance needs Pump performance Diagnostics station performance

72 QUESTIONS For More Information Contact: Kip Koszewski Glenn Hummel