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Corporate Brand The acute angle and sharp straight edges of the top half of the diamond symbol represent Yokogawa’s cutting-edge technology while the gentle curvature of the bottom half represents the warm-hearted nature of Yokogawa’s people. By balancing these two elements, Yokogawa aims to contribute toward the realization of a thriving global society in much the same way as the sun. This property is reflected in the bright yellow of the diamond. – Corporate trademark since October 1986
History of YEWFLO Vortex 1969 Yokogawa designs first Vortex meter 1995 Mass YEWFLO introduced 1982 Dual piezoelectric sensor 1988 10,000 units installed (USA) 1990 YEWFLO 100% American made 2002 Digital YEWFLO 1979 First industrial YEWFLO released 1987 First 0.5 inch Vortex flowmeter 1989 First “Smart” Vortex flowmeter 1993 Microprocessor -based “SMART” flowmeter
Product Line-Up Dual Sensor Designs High-Purity Design • Semi-conductor and • biotech industries • Electropolished • 7-15Ra finish • Redundant sensors for • critical applications High Pressure Design • 1500# & 2500# flange • ratings
Principle of Operation The analogy of a golf ball moving through the air is useful in describing vortex formation: A slow moving putt barely displaces the molecules of air The higher velocity of a chip shot causes irregular eddies to form behind the ball The velocity associated with a drive is sufficient to cause a strong, regular vortex formation behind the ball
Mountain Top Vortices Principle of Operation Vortex formation in clouds blown by a mountain top is an example from nature of the vortex phenomenon
Principle of Operation Light breeze - Laminar flow, no vortices formed NR = 0-5000 Stiff breeze - Transition flow, irregular vortex formation NR = 5000-20000 Strong wind - Turbulent flow, regular vortex pattern NR = >20000
Principle of Operation When a flowing medium strikes a non-streamlined bluff object, it separates, moves around the object and passes downstream. At the point of contact with the object, vortex swirls separate from the body on alternating sides. This separation causes a local increase in pressure and a decrease in velocity on one side and a decrease in pressure and an increase in velocity on the opposite side. The alternating velocities generate alternating pressure forces on either side of the bluff body. The frequency of these pressure changes is proportional to velocity.
Typical Vortex Sensors Thermistor Differential Switched Capacitor Integral Diaphragm YEWFLO Shedder Bar
Unique Sensor Design How Does It Work? Flow Flow hits the shedder bar, separates and due to the shape of the bar, forms vortices. The vortices create an alternating pressure differential across the bar. The bar is physically stressed toward the low pressure side of the bar. A piezoelectric crystal converts a mechanical stress into an electrical pulse. The crystals are hermetically sealed and not in contact with the process. Crystal A Crystal B L H Force
Principle of Operation The Karman vortex frequency “f” is proportional to the velocity ”v”. Therefore, it is possible to obtain the flow rate by measuring the Karman vortex frequency: f = St (v/d) where: f = Karman vortex frequency St = Strouhal number (constant) v = Velocity d = Width of vortex shedder (constant)
l What is Strouhal Number? • The Strouhal number is the ratio between the vortex interval and the shedder bar width • Usually the vortex interval (l) is about 6 times the shedder bar width (d), while the Strouhal number is the reciprocal value (~0.17) • When the Strouhal number is fixed, the velocity can be measured by counting the number of vortices
Sensor Assembly POTTING COMPOUND “O” RING SEAL CAP ASSEMBLY HERMETIC SEAL METAL TUBE INSULATOR (SHRINK TUBING) METAL DISC PIEZOELECTRIC CRYSTALS CERAMIC PLATE METAL PLATE SOLID METAL SHEDDER BAR
Unique Sensor Design “O” Ring Seal Metal Tube • No thin diaphragms to damage • No ports to plug • MTBF in excess of 250 years Piezoelectric Crystals Metal Plate Metal Disc Ceramic Plate Solid Metal Shedder Bar
Indicator/Totalizer Local Interface • Amplifier • Remote available • Gasket • High Reliability Hermetically Sealed Sensor • Body • Full ANSI rating • Shedder Bar • Solid metal • Rugged construction • No moving parts Field Proven Mechanical Construction
Why are more users applying Vortex? • Vortex Simplifies Installation & Reduces Costs • Improved Reliability • No Impulse Lines to Plug, Freeze, or Leak • Reduced potential leak points • Reduced Cost • In-line device is cost-effective in smaller lines • Reduced maintenance: No impulse lines, No Periodic Calibrations Required • Can be applied in most applications where DP-Orifice has traditionally been used • 2-wire Device • Applicable to Liquid, Gases and Steam • Wide Temperature Range to 842 F (450 C)
Vortex Flowmeter Benefits • Digital flow signal • No zero drift • Pulse output for totalizing • Low installed cost • Wide rangeability • Inherently Linear output • Low pressure drop • Liquid, steam, or gas applications • Immune to density & viscosity changes
Vortex Performance Benefits • High Accuracy +/- 0.75% of reading (liquid) +/- 1% of reading (gas, steam) • Automatic Gas Expansion Factor Correction • dramatically improves accuracy • Temperature Compensation • eliminates ambient temperature effects on the analog output • Turn Down • as high as 20:1 provides accurate control over wider process conditions
SSP ~Spectral Signal Processing • Featuring YOKOGAWA’s new, proprietary digital signal processing technique • No start-up tuning • Advanced self-diagnostics • Parameter settings made simple • Compact design • Clear, two-line display
Adaptive Noise Suppression (ANS) • ANS takes advantage of Yokogawa’s unique dual sensor design • By individually analyzing the signal from each sensor ANS can deduce which portion of the signal is flow and which portion is noise. • Improves signal to noise ratio • Continuously analyzes the incoming signals and adapts to changing noise conditions N1 S1 S2 N2 Polarization Direction S N Lift Direction Bending moment of shedder bar in lift force direction
Time SUB6 SUB5 SUB4 SUB3 Gain SUB2 SUB1 Frequency Sensitivity Curve Vortex Signal Noise Amplitude Frequency (log) SB6 SB5 SB4 SB3 SB2 SB1 Gain [Separation by SAF] Frequency Time ~ Spectral Signal Processing SSP Noisy Vortex Signal The signal is split into individual sub-bands like the frequency spectrum display of an audio graphic equalizer. The band splitting filter also applies intelligent attenuation to linearize the amplitude vs. velocity charac- teristic. Based on application information such as liquid or gas, flow span and density a predicted amplitude/sensitivity curve is computed. The results of the individual sub-band analyses are compared to the predicted sensitivity curve. Finally a tight band pass filter is focused around the vortex flow signal. Frequency Analyzing/ Intelligent Amplification Spectrum Analyzing Spectral Adaptive Filtering (SAF) Output Waveform
Signal Processing Circuitry Piezo-ceramics A/D CHARGE SPECTRUM CONVERTER CONVERTER ANALYZER 1 Output CPU Circuit CHARGE SPECTRUM A/D CONVERTER ANALYZER 2 CONVERTER Noise Ratio Setting Counter Schmitt Summer BPF Trigger B SPECTRUM A ANALYZER 3 GATE ARRAY In digitalYEWFLO the signal processing circuitry is fully digitized. This permits signal processing which had been previously performed by analog circuits (such as an adder, Schmitt trigger, and filter) to be incorporated into a gate array, resulting in reduced parts and a downsizing of the converter.
Effect of Vibration Fluid: Water Size: 50mm Setting: Default Span: 15 m3/h (2 m/s) Vibration: 1G
Low Flow Response Fluid: Water Size: 50mm Setting: Default
Simplified Parameter Settings • Frequently-used parameters grouped together in a quick access format decreases commissioning time.
New Compact Amplifier Housing • Smaller than Yewflo*E-30% • Fewer parts for improved reliability (volume reduction)
Features & Functions Summary • No start-up tuning • Automatically selects the optimum settings - even in noisy environments • Low flow stability • Accurately senses vortices at low flow rate for stable, accurate flow measurement • Backward compatible • The SSP amplifier can be retrofitted to provide the best vortex flow measurement • available today • Advanced self-diagnostics • Provides diagnostic messages on high vibration environments, excessive flow • fluctuations, and clogging or plugging in the area around the shedder bar. Analysis • of the process allows true condition-based maintenance • Simplified parameter settings • Frequently used parameters grouped together in a quick-access format decreases • commissioning time
Features & Functions Summary • Clear, parallel two line LCD display • Displays simultaneous flow rate and total along with process diagnosis • Configurable through display interface (MMI) • New compact amplifier housing • Lighter, small and easier to handle design with increased reliability and performance • Simultaneous analog and pulse outputs • Status output (flow switch function) or alarm output • BRAIN, HART and FF communications • Wide process temperature range • High temperature option to 842 deg. F (450 deg. C) • High accuracy • +/- 0.75% of reading (liquid) • +/- 1% of reading (gas, steam)
digitalYEWFLOMulti-variable Mass Vortex Flowmeter • Provides simultaneous outputs for temperature monitoring and mass flow measurement • Computes mass flow rate in real time based on the measured temperature • Displays mass flow rate and temperature on two line LCD indicator
digitalYEWFLOMulti-variable Mass Vortex Flowmeter • Decreases the need for temperature monitoring loops and thus simplifies instrumentation • Reduced openings on process pipes for inserting thermowells, that can potentially cause leakage, will slash instrumentation costs and increase the safety of the process lines • Temperature indication allows flow conditions to be monitored • The self diagnostics related to the RTD provides checks for an out of range temperature output or abnormal temperature and so provides a window into the process RTD embedded in shedder bar
Multi-variable Option ~ Flow & Temperature Built-in temp sensor • Protected in shedder bar • +/- 1 deg C (liquid), +/- 2 deg C (gas/steam); RTD Pt 1K ohm Multi-variable option • Flow & temperature values displayed • Dual output (flow: pulse, temp: 4-20) Steam mass flowrate calculation • Mass flowrate calculated using steam table and measured temperature (fixed pressure) • +/- 2% of rate accuracy Piezo sensors Shedder bar RTD sensor
1” to 4” (25-100mm) 1” to 8” (25-200mm) digitalYEWFLOMulti-variable Mass Vortex Flowmeter Specifications
Installation ConsiderationsGeneral • Pipe orientation • Ensure that pipe stays full • Meter orientation • Can be mounted in any direction • Materials of construction • Ensure that material is compatible with process fluid • Heat of Process • Ensure proper meter selection for process temperature
Successful Vortex Applications • Proper Vortex Sizing • Process conditions • Piping requirements • Full pipe
Gas Proper Piping Requirements • Attitude insensitive • Full pipe required • Good alignment of piping • Concentric Reducers if required
Proper gasket selection and installation Correct I.D. required Self Centering (Recommended) Proper material Problems occur if... gasket is too small,gasket is deformed, has shifted position, or if the mating pipe connection is misaligned.`
Reliable Flow Measurement Solution Vortex has come a long way over the year. Use Vortex as another flow measurement solution. It really does Work!
