Methodology for Liquid Ultrasonic Flow Measurement within the Laminar to Turbulent Transitional Zone Dave Seiler Daniel Measurement and Control March 25, 2014 Heavy Oil Definition!!!!the API classifies heavy oil as crudes with a gravity below 22.3 API!!!!although variously defined, the upper limit for heavy oil is 22 API gravity with a minimum viscosity of 100 cp (centipoise).!! Heavy oil deposits around the world share only one characteristic: they are challenging to produce.!! The easy crude oil is becoming harder to find 2 1!
Traditional Measurement Technology Displacement Meter Capillary Seal Inner Unit Housing Static Liquid Cam Measuring Chamber Meter Housing Blade Path of Blades Bearings Rotor Flowing Liquid Dual Rotor Sliding Vane All Displacement Meters rely on a capillary seal for good performance 3 Reynolds Number Affect on Displacement Meter Minimum slippage 4 2!
Alternative Technologies Helical Turbine Meter Ultrasonic Meter Coriolis Meter 5 Ultrasonic Meters!! Industry acceptance of Liquid Ultrasonic is driving technology growth!! Technology is well entrenched into custody transfer type applications!! Manufacturers are continuing to invest and drive for ease of use and improvements in measurement!! Customers are applying the technology into more complex applications 6 3!
Transit Time USM How It Works?!! Measures transit times of ultrasonic pulses!! Transducer locations placed for optimum measurement accuracy!! Transducers act alternately as transmitter and receiver Multipath Liquid USM Multipath Liquid USM n Vaverage = " wivi i= 1 = 0.1382! v + 0.3618! v + 0.3618! v + 0.1382! v Q = Vaverage! A 1 where Q = flow rate A = cross sectional area of the Meter bore 2 3 Flow 4 7 Liquid Ultrasonic Meter High Viscosity Flow Measurement Challenge! Measurements are dependent on velocity profile! Velocity profile is Reynolds number (Re) (i.e. flow regime) dependent! Turbulent: Re>5000! Laminar: Re<2000! Transitional 2000<Re<5000! Liquid ultrasonic flow meters perform the best in the turbulent regime! Measurement non-linearity increases rapidly as Re<10 4 in conventional flow measurement applications 8 4!
The Challenge!! Develop a transducer capable of transmitting a signal through a high viscosity fluid Transducer Housing Transducer Capsule Transducer Retainer!! Accurately measure volume through all flow regimes including Transitional 9 Objective Develop a methodology to measure high viscosity fluid flow rate using liquid ultrasonic meters with high accuracy required for custody transfer applications 1 0 5!
Typical Meter Run API 5.8 11 Installations Flow Elbow Flow Tee or Header 1 2 6!
Conventional Flow Measurement Error vs. Reynolds Number Curves Experimental Error Laminar Transition Turbulent 1 3 Conventional Flow Measurement Error vs. Reynolds Number Curves Laminar Transition Turbulent 1 4 7!
Conventional Flow Measurement Error Curves 1 5 Conventional Flow Measurement Error Curves 1 6 8!
Potential Solutions! Correct meter error without changing the fluid flow velocity profile (electronic corrections in meter firmware)! Difficult to formulate algorithms across flow regimes and for different upstream piping configurations! Modify fluid flow velocity profile to one that can be accurately measured! Utilize special (custom) flow conditioners! Employ a combination of both of the above for the entire Reynolds number range 1 7 Proposed Piping Solutions CPA Plate 3D With large upstream pipe Without large upstream pipe 1 8 9!
Flow Development with an Upstream Diffuser -! Velocity Profile "! Average Velocity along path 1 9 Flow Development with an Upstream Diffuser!! Re_1000_TRANS_VenturiC_3DHEAD_PORTS_ DivConv_POS_VelProfDev.avi!! Re_1985 TRANS_VenturiC_3DHEAD_PORTS_POS_VelP rofdev.avi!! Re_6150 Turb_VenturiC_3DHEAD_PORTS_POS_VelProf Dev.avi!! Re_6150_Turb_VenturiC_3DHEAD_PORTS_Div Conv_POS_VelProfDev.avi 2 0 10!
Daniel Test Loop - Houston!! High viscosity flow loop! up to 1000cSt! Temperature controlled! 8 PD Master Meter! 18 SVP 2 1 Performance Results - 8 Liquid Ultrasonic Meter with Proposed Piping!! SVP proves the master meter!! Master proves the Liquid USM!! Master Meter re-proven 2 2 11!
Performance Results - 8 Liquid Ultrasonic Meter with Proposed Piping 2 3 Liquid Ultrasonic Flow Meter Performance for Different Viscous Fluids 2 4 12!
Performance of Different Size Meters 2 5 Summary! CFD provided additional insight to improve liquid ultrasonic flow meter performance with Gaussian quadrature integration with Chebyshev s polynomials of second kind! Flow conditioning has a significant effect on 4 path liquid ultrasonic meter performance in low Reynolds number regions! Employing the proposed piping solutions can achieve the accuracy required for custody transfer within laminar to turbulent transitional zone! Utilization of flow conditioning upstream of a reducer provided approximately 80% less pressure drop compared to conventional bore matched flow conditioning 2 6 13!
People who say it cannot be done should not interrupt those who are doing it." George Bernard Shaw 2 7 14!