NAPIM studies show Zahn is the least accurate Efflux Cup, this is a study showing the Shell should be the Efflux Cup of choice when attempting to characterize the flow properties of a series of water based inks or other systems involving significant differences in surface tension.
This document presents guidelines for designing rigging systems (gating and risering) for different types of castings, including light alloys, ductile iron, and steel. For light alloys, the rigging system is designed to promote sequential solidification and minimize turbulence during filling to prevent oxide entrapment. Specific guidelines are provided for part orientation, locating the parting plane, sizing the sprue and runners, and using filters/screens. The document aims to compile common industry rules and methods engineer practices for different casting materials.
The document discusses casting processes and the importance of fluid flow. It describes the components of a gating system including the sprue, runner, ingates and riser. It explains that the gating system helps trap contaminants in the molten metal and regulates flow into the mold cavity to ensure proper solidification. The document also covers topics like riser design and function, types of gates, permeability, and cleaning and finishing of castings.
Gauge glasses, ball floats, chain floats, magnetic floats, conductivity probes, and differential pressure detectors are common level instrumentation types described. Gauge glasses simply indicate level visually in a transparent tube. Ball and chain floats are connected to indicators via rods or chains to show remote readings. Magnetic floats track level magnetically outside a tube. Conductivity probes detect level electrically. Differential pressure detectors compare pressures below and above the liquid level. Specific volume is the standard unit used for vapors and steam, accounting for density changes that affect pressure readings.
This document provides information about the Saybolt viscometer, a device used to measure the viscosity of fluids. It defines viscosity and describes how the Saybolt viscometer works by measuring the time it takes for a fixed volume of fluid to flow through a temperature-controlled orifice. The document discusses the advantages of accurate temperature control and direct viscosity comparisons, and the disadvantages of potential inaccuracies. It also notes the Saybolt viscometer is commonly used to test petroleum products and measure viscosities in the field.
this section speaks about the quantity flow meter and its different types i.e. positive displacement flow meter and metering pump, it comprises discussion on mass flow meter, coriolis flow meter, variable reluctance tacho generator and linear resistance element flow meter.
This document describes an ink composition for ink jet printers. It contains an aqueous carrier medium, a pigment dispersion or dye, and a special type of penetrant. The penetrant is an aliphatic diol with at least 6 carbon atoms, high water solubility, and is selected from compounds with 2 or more carbon substituents or hexene diols. These penetrants increase ink drying speed without destabilizing pigment dispersions or reducing reliability. The inks exhibit rapid drying, storage stability, reliable performance, and good print quality.
This document discusses hopper design for storing powdered materials. It begins by explaining the historical development of hopper design, noting that Andrew Jenike's work in the 1960s established the theory and methods for properly designing hoppers based on material flow properties. The document then discusses the different modes of material flow in hoppers - mass flow, funnel flow, and expanded flow. It identifies problems that can occur in hopper design like ratholing, arching, or segregation. The key to proper design is predicting mass flow, which depends on material properties like internal friction that must be tested for using equipment like the Jenike Shear Tester. Mass flow hoppers have advantages over funnel flow but require more headroom.
Basic Screw Geometry: Things Your Extruder Screw Designer Never Told You Abou...R&B Plastics Machinery
This document provides an overview of basic screw geometry for single screw extruders. It defines key terms like flighted length, screw diameter, and L/D ratio. It describes the different sections of the screw - feed, transition, and metering - and factors that influence their design like material properties, length, and compression ratio calculations. The document also discusses two-stage vented screw designs and how to calculate compression ratios and pumping capacities for different screw configurations.
This document presents guidelines for designing rigging systems (gating and risering) for different types of castings, including light alloys, ductile iron, and steel. For light alloys, the rigging system is designed to promote sequential solidification and minimize turbulence during filling to prevent oxide entrapment. Specific guidelines are provided for part orientation, locating the parting plane, sizing the sprue and runners, and using filters/screens. The document aims to compile common industry rules and methods engineer practices for different casting materials.
The document discusses casting processes and the importance of fluid flow. It describes the components of a gating system including the sprue, runner, ingates and riser. It explains that the gating system helps trap contaminants in the molten metal and regulates flow into the mold cavity to ensure proper solidification. The document also covers topics like riser design and function, types of gates, permeability, and cleaning and finishing of castings.
Gauge glasses, ball floats, chain floats, magnetic floats, conductivity probes, and differential pressure detectors are common level instrumentation types described. Gauge glasses simply indicate level visually in a transparent tube. Ball and chain floats are connected to indicators via rods or chains to show remote readings. Magnetic floats track level magnetically outside a tube. Conductivity probes detect level electrically. Differential pressure detectors compare pressures below and above the liquid level. Specific volume is the standard unit used for vapors and steam, accounting for density changes that affect pressure readings.
This document provides information about the Saybolt viscometer, a device used to measure the viscosity of fluids. It defines viscosity and describes how the Saybolt viscometer works by measuring the time it takes for a fixed volume of fluid to flow through a temperature-controlled orifice. The document discusses the advantages of accurate temperature control and direct viscosity comparisons, and the disadvantages of potential inaccuracies. It also notes the Saybolt viscometer is commonly used to test petroleum products and measure viscosities in the field.
this section speaks about the quantity flow meter and its different types i.e. positive displacement flow meter and metering pump, it comprises discussion on mass flow meter, coriolis flow meter, variable reluctance tacho generator and linear resistance element flow meter.
This document describes an ink composition for ink jet printers. It contains an aqueous carrier medium, a pigment dispersion or dye, and a special type of penetrant. The penetrant is an aliphatic diol with at least 6 carbon atoms, high water solubility, and is selected from compounds with 2 or more carbon substituents or hexene diols. These penetrants increase ink drying speed without destabilizing pigment dispersions or reducing reliability. The inks exhibit rapid drying, storage stability, reliable performance, and good print quality.
This document discusses hopper design for storing powdered materials. It begins by explaining the historical development of hopper design, noting that Andrew Jenike's work in the 1960s established the theory and methods for properly designing hoppers based on material flow properties. The document then discusses the different modes of material flow in hoppers - mass flow, funnel flow, and expanded flow. It identifies problems that can occur in hopper design like ratholing, arching, or segregation. The key to proper design is predicting mass flow, which depends on material properties like internal friction that must be tested for using equipment like the Jenike Shear Tester. Mass flow hoppers have advantages over funnel flow but require more headroom.
Basic Screw Geometry: Things Your Extruder Screw Designer Never Told You Abou...R&B Plastics Machinery
This document provides an overview of basic screw geometry for single screw extruders. It defines key terms like flighted length, screw diameter, and L/D ratio. It describes the different sections of the screw - feed, transition, and metering - and factors that influence their design like material properties, length, and compression ratio calculations. The document also discusses two-stage vented screw designs and how to calculate compression ratios and pumping capacities for different screw configurations.
TangentFlow Technical Paper FINAL 221015 OCT 22 2015Corbin Coyes
The document discusses the design and testing of a new ball valve insert called the vortex insert. The goal was to improve the efficiency and reliability of sucker rod pumps. Laboratory testing found that a prototype insert with a 10mm clockwise helical twist reduced pressure drop by an average of 40% compared to conventional bar-bottom inserts, resulting in 58% more flow. Field data also showed increased production and a 25% reduction in operating costs after installing the new inserts. The vortex insert design aims to minimize issues like pressure drop, gas breakout, and solids buildup that reduce pump efficiency by forcing fluid into a stabilizing vortex motion through the ball valve.
This document summarizes a study on the strength and shrinkage properties of alkali-activated slag concrete (AASC) placed in a large concrete column. Key findings include:
1) The AASC had improved workability over time compared to ordinary portland cement concrete, with minimal slump loss over 2 hours.
2) The temperature development in the AASC column was similar to a blended cement column and slower than an ordinary portland cement column, with a smaller temperature difference between the interior and exterior.
3) The compressive strength of the AASC column was identical to ordinary portland cement concrete and stronger than blended cement concrete at 28 and 91 days.
4) Embedded strain gauges
This document discusses balloon concrete formwork, which uses an inflated balloon as a single form for concrete structures. The balloon is inflated with bumps that form windows and doors, and welded wire mesh is cut to size and sprayed with concrete to strengthen the structure. Foamcrete, which has a higher proportion of air bubbles, is used as the concrete mix. The document outlines the design, materials, fabrication, installation, applications, and advantages of balloon concrete formwork, concluding that it provides a low-cost and efficient construction method for large concrete domes.
This presentation is for my last Cambridge Rheology course lecture. The presentation links course work with research that had been carried out in the Department. The presentation has been modified a little to aid web clarity.
Produced water reinjection (PWRI) is one of the most usual ways of produced water reuse in mature fields with high water cut.
The relationship between water quality and injectivity decline in wells is well known and it is particularly important in mature
fields, such as Barrancas, an old field located in Mendoza –Argentina, with more than 40 years of water injection. In this
reservoir significant injectivity losses were recorded when fresh water was replaced by produced water in the 90´s.
Formation Damage mechanism is mainly caused by external cake. Particles are principally, iron sulfide, calcium carbonate,
and oil droplets.
This document describes the author's experience over 12 years commercializing their invention of forced pulsed waterjet (FPWJ) technology. It began as fundamental research but faced many challenges to become commercially successful. The author provides a brief overview of the FPWJ technique and its benefits. They then describe the evolution of their FPWJ machines over 12 years, starting with early prototype machines that helped demonstrate applications but had reliability issues, to later pre-commercial machines used for contracts and demonstrations, highlighting they learned from mistakes along the way. The goal is to advise others on commercializing inventions by sharing the hardships endured to succeed with FPWJ technology.
22 year stress relaxation and strain limit testing of pvc pipesSpring Holidays Ltd
This paper is a report of continuing tests that were started in January of 1977. Samples of PVC pipe were placed on long-term test under various levels of constant strain. The objectives
of the tests were to determine stress relaxation characteristics and constant strain failure data.
IRJET- Analysis of Cooling Fluid Interaction and Force Generated in a Pis...IRJET Journal
This document discusses analysis of cooling fluid interaction and force generated in a piston cylinder assembly. It begins with an abstract that outlines the goal of analyzing cooling fluid effects and cavitation in internal combustion engines using simulation. It then provides background on cavitation phenomena and stages. It describes the operation of internal combustion diesel engines, including the four strokes and cooling system. Equations are presented for forces on piston cylinder components under various assumptions. The document aims to simulate cavitation effects on cylinder liners and identify methods to increase engine component life.
Engineering Practice Magazine - January 2020Karl Kolmetz
How to Design and Optimize Sieve Trays
Key Process Considerations for Pipeline Design Basis
How Does Cycles Increase in Cooling Towers Save Money?
Chernobyl Lessons in Process Safety
Adding Value to the Crude Oil –
Distillation Process Unit
This document discusses recent trends and the future of ultra deepwater oil field developments. It summarizes that developments in ultra deepwater have very high costs, prompting companies to consider more standardized and innovative solutions. Subsea wells and FPSOs have become the standard for field development below depths of around 2500-3000 meters. New technologies like subsea separation, direct electrical heating of flowlines, and subsea power distribution are being successfully implemented and will likely become more common. Future field developments are expected to utilize more standardized components coupled with innovative technologies to reduce costs and maximize recovery in ultra deepwater environments over the next 5-10 years.
This patent describes a headliner laminate made of multiple layers including polyurethane foam and agricultural fibers such as jute, sisal, or kenaf. The agricultural fibers are made into a sheet incorporating a binder and placed on both sides of a foam layer saturated with adhesive. A decorative material and backing are applied and the layers are compressed together to distribute the adhesive and laminate them. The use of agricultural fibers instead of fiberglass addresses environmental issues with fiberglass waste.
This document summarizes a simulation of internal fuel flow in a multi-hole diesel fuel injector nozzle. The study aims to validate CFD models of flow at low needle lifts without cavitation and perform a grid sensitivity analysis. Results show multiple vortexes forming in the nozzle sac and hole entrance. Grid independence is approached with finer grids, and predictions of mean axial velocity generally agree with experimental laser Doppler velocimetry data, though some discrepancies remain at low velocities near walls. The study enhances understanding of non-cavitating flow fields in these injectors.
This document provides an overview of artificial lift methods and inflow performance relationships for oil and gas wells. It discusses:
1) The key factors that influence a well's inflow performance curve, including reservoir type, pressure, and permeability. Common reservoir types include solution gas drive, water drive, and gas cap expansion drive.
2) How productivity index (PI) is calculated and used to estimate well performance. PI represents the flow rate per unit of pressure drop and can help design artificial lift installations.
3) Other concepts like specific PI, which normalizes PI by pay zone thickness, and how water cut influences PI calculations.
1. The document describes an experiment conducted to determine the rheological properties of viscosity and yield point of a drilling fluid sample using a Fann viscometer.
2. Key aspects of the experiment included preparing the mud sample, measuring its viscosity at 300 and 600 RPM, and determining its plastic viscosity and apparent viscosity. Calibration of the Marsh funnel and factors affecting rheological properties are also discussed.
3. Sources of potential error in measuring viscosity are described, such as improper mud weight, excess or insufficient fluid, and improper reading of the measuring scale.
Achievements In Industrial Ozone Bleaching PpiJCHostachy
This document discusses the benefits and achievements of ozone bleaching in the pulp and paper industry over the past 19 years. Ozone bleaching reduces bleaching costs by 20-32% and effluent loads compared to traditional ECF bleaching sequences. It allows high brightness levels above 92% ISO while decreasing brightness reversion and reducing extractives content by 50-75%. Ozone bleaching is now a well-proven technology used in 22 mills worldwide producing both hardwood and softwood pulps.
This document provides an overview of different types of evaporators, including batch pan, natural circulation, rising film tubular, falling film tubular, rising/falling film tubular, forced circulation, wiped film, and plate evaporators. It describes the operating principles and key advantages of each type. The document focuses on describing rising/falling film plate evaporators in detail, including their design, applications processing foods, juices, dairy products, and more, and their advantages over tubular evaporators.
The Application of a Thin Liquid Film at the Outlet of a Tesla TurbineIJARIDEA Journal
- The document discusses maintaining a thin liquid condensate film at the outlet of a Tesla turbine. It presents an analytic model for calculating the film thickness and compares it to results from a numerical simulation.
- The model analyzes laminar thin film condensation on a rotating disk under the influence of radial gas flow and centrifugal force from disk rotation. It aims to determine if the film can be sustained at the turbine outlet.
- Prior research has examined condensation in Tesla turbines and between parallel rotating disks, determining heat transfer values and film thicknesses. However, little literature exists on condensation specifically within a Tesla turbine gap.
The document discusses drill stem testing (DST), which is used to evaluate reservoir properties. It describes the key components of a DST tool, including pressure recorders, test valves, packers, and more. It also outlines the steps to design a DST plan, considering factors like the test interval, packer selection and location, choke selection, and more. Finally, it explains how to execute a DST, interpreting the pressure chart by describing the initial flow, initial shut-in, final flow, and final shut-in periods marked on a sample chart.
The document discusses fuel injection and spray formation in diesel engines. It examines the effects of injection pressure on engine performance and emissions. The results of an experiment showed that brake thermal efficiency peaked at an injection pressure of 200 bars, while brake specific fuel consumption was lowest. CO and smoke emissions decreased with higher injection pressure, while UHC first decreased and then increased as pressure became too high. Optimal injection pressure was found to be 200 bars for a 20% biodiesel blend. Cavitation in the fuel injector nozzle enhances spray atomization and improves combustion. Nozzle geometry and injection conditions can affect cavitation.
The Steadfast and Reliable Bull: Taurus Zodiac Signmy Pandit
Explore the steadfast and reliable nature of the Taurus Zodiac Sign. Discover the personality traits, key dates, and horoscope insights that define the determined and practical Taurus, and learn how their grounded nature makes them the anchor of the zodiac.
Ellen Burstyn: From Detroit Dreamer to Hollywood Legend | CIO Women MagazineCIOWomenMagazine
In this article, we will dive into the extraordinary life of Ellen Burstyn, where the curtains rise on a story that's far more attractive than any script.
TangentFlow Technical Paper FINAL 221015 OCT 22 2015Corbin Coyes
The document discusses the design and testing of a new ball valve insert called the vortex insert. The goal was to improve the efficiency and reliability of sucker rod pumps. Laboratory testing found that a prototype insert with a 10mm clockwise helical twist reduced pressure drop by an average of 40% compared to conventional bar-bottom inserts, resulting in 58% more flow. Field data also showed increased production and a 25% reduction in operating costs after installing the new inserts. The vortex insert design aims to minimize issues like pressure drop, gas breakout, and solids buildup that reduce pump efficiency by forcing fluid into a stabilizing vortex motion through the ball valve.
This document summarizes a study on the strength and shrinkage properties of alkali-activated slag concrete (AASC) placed in a large concrete column. Key findings include:
1) The AASC had improved workability over time compared to ordinary portland cement concrete, with minimal slump loss over 2 hours.
2) The temperature development in the AASC column was similar to a blended cement column and slower than an ordinary portland cement column, with a smaller temperature difference between the interior and exterior.
3) The compressive strength of the AASC column was identical to ordinary portland cement concrete and stronger than blended cement concrete at 28 and 91 days.
4) Embedded strain gauges
This document discusses balloon concrete formwork, which uses an inflated balloon as a single form for concrete structures. The balloon is inflated with bumps that form windows and doors, and welded wire mesh is cut to size and sprayed with concrete to strengthen the structure. Foamcrete, which has a higher proportion of air bubbles, is used as the concrete mix. The document outlines the design, materials, fabrication, installation, applications, and advantages of balloon concrete formwork, concluding that it provides a low-cost and efficient construction method for large concrete domes.
This presentation is for my last Cambridge Rheology course lecture. The presentation links course work with research that had been carried out in the Department. The presentation has been modified a little to aid web clarity.
Produced water reinjection (PWRI) is one of the most usual ways of produced water reuse in mature fields with high water cut.
The relationship between water quality and injectivity decline in wells is well known and it is particularly important in mature
fields, such as Barrancas, an old field located in Mendoza –Argentina, with more than 40 years of water injection. In this
reservoir significant injectivity losses were recorded when fresh water was replaced by produced water in the 90´s.
Formation Damage mechanism is mainly caused by external cake. Particles are principally, iron sulfide, calcium carbonate,
and oil droplets.
This document describes the author's experience over 12 years commercializing their invention of forced pulsed waterjet (FPWJ) technology. It began as fundamental research but faced many challenges to become commercially successful. The author provides a brief overview of the FPWJ technique and its benefits. They then describe the evolution of their FPWJ machines over 12 years, starting with early prototype machines that helped demonstrate applications but had reliability issues, to later pre-commercial machines used for contracts and demonstrations, highlighting they learned from mistakes along the way. The goal is to advise others on commercializing inventions by sharing the hardships endured to succeed with FPWJ technology.
22 year stress relaxation and strain limit testing of pvc pipesSpring Holidays Ltd
This paper is a report of continuing tests that were started in January of 1977. Samples of PVC pipe were placed on long-term test under various levels of constant strain. The objectives
of the tests were to determine stress relaxation characteristics and constant strain failure data.
IRJET- Analysis of Cooling Fluid Interaction and Force Generated in a Pis...IRJET Journal
This document discusses analysis of cooling fluid interaction and force generated in a piston cylinder assembly. It begins with an abstract that outlines the goal of analyzing cooling fluid effects and cavitation in internal combustion engines using simulation. It then provides background on cavitation phenomena and stages. It describes the operation of internal combustion diesel engines, including the four strokes and cooling system. Equations are presented for forces on piston cylinder components under various assumptions. The document aims to simulate cavitation effects on cylinder liners and identify methods to increase engine component life.
Engineering Practice Magazine - January 2020Karl Kolmetz
How to Design and Optimize Sieve Trays
Key Process Considerations for Pipeline Design Basis
How Does Cycles Increase in Cooling Towers Save Money?
Chernobyl Lessons in Process Safety
Adding Value to the Crude Oil –
Distillation Process Unit
This document discusses recent trends and the future of ultra deepwater oil field developments. It summarizes that developments in ultra deepwater have very high costs, prompting companies to consider more standardized and innovative solutions. Subsea wells and FPSOs have become the standard for field development below depths of around 2500-3000 meters. New technologies like subsea separation, direct electrical heating of flowlines, and subsea power distribution are being successfully implemented and will likely become more common. Future field developments are expected to utilize more standardized components coupled with innovative technologies to reduce costs and maximize recovery in ultra deepwater environments over the next 5-10 years.
This patent describes a headliner laminate made of multiple layers including polyurethane foam and agricultural fibers such as jute, sisal, or kenaf. The agricultural fibers are made into a sheet incorporating a binder and placed on both sides of a foam layer saturated with adhesive. A decorative material and backing are applied and the layers are compressed together to distribute the adhesive and laminate them. The use of agricultural fibers instead of fiberglass addresses environmental issues with fiberglass waste.
This document summarizes a simulation of internal fuel flow in a multi-hole diesel fuel injector nozzle. The study aims to validate CFD models of flow at low needle lifts without cavitation and perform a grid sensitivity analysis. Results show multiple vortexes forming in the nozzle sac and hole entrance. Grid independence is approached with finer grids, and predictions of mean axial velocity generally agree with experimental laser Doppler velocimetry data, though some discrepancies remain at low velocities near walls. The study enhances understanding of non-cavitating flow fields in these injectors.
This document provides an overview of artificial lift methods and inflow performance relationships for oil and gas wells. It discusses:
1) The key factors that influence a well's inflow performance curve, including reservoir type, pressure, and permeability. Common reservoir types include solution gas drive, water drive, and gas cap expansion drive.
2) How productivity index (PI) is calculated and used to estimate well performance. PI represents the flow rate per unit of pressure drop and can help design artificial lift installations.
3) Other concepts like specific PI, which normalizes PI by pay zone thickness, and how water cut influences PI calculations.
1. The document describes an experiment conducted to determine the rheological properties of viscosity and yield point of a drilling fluid sample using a Fann viscometer.
2. Key aspects of the experiment included preparing the mud sample, measuring its viscosity at 300 and 600 RPM, and determining its plastic viscosity and apparent viscosity. Calibration of the Marsh funnel and factors affecting rheological properties are also discussed.
3. Sources of potential error in measuring viscosity are described, such as improper mud weight, excess or insufficient fluid, and improper reading of the measuring scale.
Achievements In Industrial Ozone Bleaching PpiJCHostachy
This document discusses the benefits and achievements of ozone bleaching in the pulp and paper industry over the past 19 years. Ozone bleaching reduces bleaching costs by 20-32% and effluent loads compared to traditional ECF bleaching sequences. It allows high brightness levels above 92% ISO while decreasing brightness reversion and reducing extractives content by 50-75%. Ozone bleaching is now a well-proven technology used in 22 mills worldwide producing both hardwood and softwood pulps.
This document provides an overview of different types of evaporators, including batch pan, natural circulation, rising film tubular, falling film tubular, rising/falling film tubular, forced circulation, wiped film, and plate evaporators. It describes the operating principles and key advantages of each type. The document focuses on describing rising/falling film plate evaporators in detail, including their design, applications processing foods, juices, dairy products, and more, and their advantages over tubular evaporators.
The Application of a Thin Liquid Film at the Outlet of a Tesla TurbineIJARIDEA Journal
- The document discusses maintaining a thin liquid condensate film at the outlet of a Tesla turbine. It presents an analytic model for calculating the film thickness and compares it to results from a numerical simulation.
- The model analyzes laminar thin film condensation on a rotating disk under the influence of radial gas flow and centrifugal force from disk rotation. It aims to determine if the film can be sustained at the turbine outlet.
- Prior research has examined condensation in Tesla turbines and between parallel rotating disks, determining heat transfer values and film thicknesses. However, little literature exists on condensation specifically within a Tesla turbine gap.
The document discusses drill stem testing (DST), which is used to evaluate reservoir properties. It describes the key components of a DST tool, including pressure recorders, test valves, packers, and more. It also outlines the steps to design a DST plan, considering factors like the test interval, packer selection and location, choke selection, and more. Finally, it explains how to execute a DST, interpreting the pressure chart by describing the initial flow, initial shut-in, final flow, and final shut-in periods marked on a sample chart.
The document discusses fuel injection and spray formation in diesel engines. It examines the effects of injection pressure on engine performance and emissions. The results of an experiment showed that brake thermal efficiency peaked at an injection pressure of 200 bars, while brake specific fuel consumption was lowest. CO and smoke emissions decreased with higher injection pressure, while UHC first decreased and then increased as pressure became too high. Optimal injection pressure was found to be 200 bars for a 20% biodiesel blend. Cavitation in the fuel injector nozzle enhances spray atomization and improves combustion. Nozzle geometry and injection conditions can affect cavitation.
The Steadfast and Reliable Bull: Taurus Zodiac Signmy Pandit
Explore the steadfast and reliable nature of the Taurus Zodiac Sign. Discover the personality traits, key dates, and horoscope insights that define the determined and practical Taurus, and learn how their grounded nature makes them the anchor of the zodiac.
Ellen Burstyn: From Detroit Dreamer to Hollywood Legend | CIO Women MagazineCIOWomenMagazine
In this article, we will dive into the extraordinary life of Ellen Burstyn, where the curtains rise on a story that's far more attractive than any script.
Enhancing Adoption of AI in Agri-food: IntroductionCor Verdouw
Introduction to the Panel on: Pathways and Challenges: AI-Driven Technology in Agri-Food, AI4Food, University of Guelph
“Enhancing Adoption of AI in Agri-food: a Path Forward”, 18 June 2024
Unlocking WhatsApp Marketing with HubSpot: Integrating Messaging into Your Ma...Niswey
50 million companies worldwide leverage WhatsApp as a key marketing channel. You may have considered adding it to your marketing mix, or probably already driving impressive conversions with WhatsApp.
But wait. What happens when you fully integrate your WhatsApp campaigns with HubSpot?
That's exactly what we explored in this session.
We take a look at everything that you need to know in order to deploy effective WhatsApp marketing strategies, and integrate it with your buyer journey in HubSpot. From technical requirements to innovative campaign strategies, to advanced campaign reporting - we discuss all that and more, to leverage WhatsApp for maximum impact. Check out more details about the event here https://events.hubspot.com/events/details/hubspot-new-delhi-presents-unlocking-whatsapp-marketing-with-hubspot-integrating-messaging-into-your-marketing-strategy/
❼❷⓿❺❻❷❽❷❼❽ Dpboss Matka Result Satta Matka Guessing Satta Fix jodi Kalyan Final ank Satta Matka Dpbos Final ank Satta Matta Matka 143 Kalyan Matka Guessing Final Matka Final ank Today Matka 420 Satta Batta Satta 143 Kalyan Chart Main Bazar Chart vip Matka Guessing Dpboss 143 Guessing Kalyan night
During the budget session of 2024-25, the finance minister, Nirmala Sitharaman, introduced the “solar Rooftop scheme,” also known as “PM Surya Ghar Muft Bijli Yojana.” It is a subsidy offered to those who wish to put up solar panels in their homes using domestic power systems. Additionally, adopting photovoltaic technology at home allows you to lower your monthly electricity expenses. Today in this blog we will talk all about what is the PM Surya Ghar Muft Bijli Yojana. How does it work? Who is eligible for this yojana and all the other things related to this scheme?
Efficient PHP Development Solutions for Dynamic Web ApplicationsHarwinder Singh
Unlock the full potential of your web projects with our expert PHP development solutions. From robust backend systems to dynamic front-end interfaces, we deliver scalable, secure, and high-performance applications tailored to your needs. Trust our skilled team to transform your ideas into reality with custom PHP programming, ensuring seamless functionality and a superior user experience.
Prescriptive analytics BA4206 Anna University PPTFreelance
Business analysis - Prescriptive analytics Introduction to Prescriptive analytics
Prescriptive Modeling
Non Linear Optimization
Demonstrating Business Performance Improvement
1. Efflux Cup
Reprint 142
NAPIM Studies Show Zahn Is Least Accurate Efflux Cup
By Jean S. Lavelle, NIPRI Staff, Lehigh University
Reprinted with Permission from Flexo, June 1988
Efflux cups are important tools for adjusting and controlling the important to note that the drain time is particularly sensitive to the
flow properties of gravure and flexographic inks. Ely [1980] radius of the orifice.
stressed the economic importance of obtaining correct ink
dilutions; his data indicated that a one second rise in drain time, Efflux cups were developed as inexpensive robust alternatives
18 instead of 17 seconds, can increase ink consumption on the to glass capillary viscometers. The difference in features among
press by 18 percent using a #2 Zahn and 7.3 percent using a #3 the four major efflux cups will be discussed.
Shell. On the other hand, there are cases where two inks having
the same Zahn cup reading had completely different printing Ford Cup
characteristics [Bates, 1982]. The Ford cup was developed in the 1920’s for thinning
automotive paints. As seen in the schematic in figure 2(a), it
The National Association of Printing Ink Manufacturers (NAPIM) consists of a hollow cylinder with a conical base, small orifice
has commissioned its research arm, the National Printing Ink and a stubby capillary with a 100-degree conical entrance. It is
Research Institute (NPIRI), to undertake a scientific study of the normally filled by pouring the liquid into the cup. Although the
printability of flexographic inks. A study of the flow properties of precision of test measurements is reasonable (see table 1), it has
the inks by efflux cups and other appropriate instruments is an not been widely adopted by the ink industry.
essential part of the program.
Zahn Cup
This article summarizes the results of the experiments in the The Zahn cup, which is filled by dipping into the liquid, was
NPIRI laboratories. It also encompasses a brief literature search developed in the 1930’s for quality control of varnishes. As
on the four major efflux cups — the Ford, Zahn, Shell and ISO. shown in figure 2(b), the capillary length corresponds to the
The major intent is to present the limitations of these deceptively thickness of the wall, about 2 mils or 0.05 mm.
simple devices and to give the reader an appreciation of the
numerous factors that influence their performance. Topics to be The short capillary coupled with the simple design makes the
discussed are: Zahn cup not only easy to clean but also inexpensive. It is
A. The design of efflux cups undoubtedly for these reasons that it has grown to be the most
B. Laboratory experiments with Zahn and Shell cups popular efflux cup in use not only throughout the paint and
1. Calibration varnish industries but also in the flexo and gravure industries.
2. Influence of surface tension
3. Influence of temperature These same features in the Zahn present serious flow problems.
4. Effect of shear rate According to Owczarek [1968], the untapered entrance does not
allow formation of a parabolic flow pattern. Instead, the fluid
Design of Efflux Cups contracts as it enters the short capillary and a portion splits off
Efflux cups are variations of a capillary and forms eddies along the wall (see figure 3). Owczarek also
viscometer, which is intended to states that the flow pattern is dependent upon the surface
determine the viscosity of Newtonian tension of the liquid. Patton [1979] arrived at a similar conclusion.
fluids by measuring the time required for
the liquid to drain. The force pushing the In addition, the stream of fluid does not exhibit a sharp break as
liquid through the capillary and the drain the cup empties (see figure 4). This “dribbling” makes it difficult
time is related to a number of parameters to time the endpoint and probably contributes to the poor
which are described in detail in the
accompanying article.
For the purpose of this discussion, it is
important to note that the basic
equations assume a parabolic flow
profile, such as illustrated in figure 1. This
requirement can be met only with a Figure 1. Parabolic flow
sufficiently long capillary. It is also profile of Newtonian
fluid through capillary. Figure 2. Schematic diagram of Ford, Zahn, Shell, and ISO efflux cups.
RP142_Page1
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2. Efflux Cup
Reprint 142
[The Zahn cup] reproducibility of test results shown in Shell Cup
table 1, obtained when one cup was Like the Zahn, the Shell cup is a dip-type efflux cup. As seen in
has grown to be circulated. figure 2(c), it has a longer capillary than the Zahn (25 mm vx. 0.05
mm) which improves the smoothness of flow [Mewis, 1980] and
Another problem is that since drain time increases the probability of obtaining a parabolic flow profile.
the most is inversely proportional to the fourth However, the untapered entrance to the capillary can present the
power of the radius, minor variations in same problems of turbulent flow and surface tension
popular efflux orifice size lead to poorer reproducibility dependency as with the Zahn cup.
when different cups are used [Bagnall,
cup in use not 1982; Knorps, 1980]. Moreover, cup As seen in figure 4, the endpoint is considerably sharper than on
capacity, intended to be 44 mL, actually the Zahn. In turn, the precision of test measurements is much
only throughout ranges from 43-48 mL among cups from improved (see table 1). There is only one manufacturer and the
several manufacturers. volume is always 23 mL.
the paint
Because of the greater precision, the Gravure Technical
and varnish Association [Vomacka, 1968] recommended that the Shell cup
be adopted as the industry standard. However, the change from
industries but the Zahn to the Shell has not been accomplished to any great
degree. A similar situation exists in the flexo industry [Bagnall,
also in the flexo 1982].
and gravure ISO Cup
In order to solve some of the problems which evolved from
industries. attempts to use a variety of flow cups as viscometers for
complex fluids, the International Standards Organization (ISO) in
1965 authorized a task group to design an international flow cup.
The rationale for the final design of the cup has been described
in detail by McKelvie [1970].
As seen in figure 2(d), key features of the ISO cup include the
120-degree angle of the conical entrance and a 2 mm capillary.
McKelvie also stressed the importance of smoothness of the
interior surface. Particularly germane is the fact that the ISO cup
Figure 3. Flow in duct with sudden has the best precision of the four cups (see table 1).
contraction of its cross-section.
Experiments with Zahn and Shell Cups Calibration
The reliability of test results can only be judged by cup
performance during calibration. The importance of calibration
has been stressed by Euverard [1948, 1950], McKelvie [1970],
and Patton [1979], and both the ASTM and ISO test methods
require this procedure.
TABLE 1. PRECISION OF EFFLUX CUPS
Single-operator Interlaboratory
Original
Cup Test Method Repeatability Reproducibility
Year
(% relative) (% relative)
Ford ASTM D1200 1952 8 20
Zahn ASTM D4212 1982 11* 33*
Shell ASTM D4212 1982 9 18
ISO ISO 2431 1980 5 10
Figure 4. High speed photographs of * using identical cups.
endpoint on Zahn cup (top) and Shell cup
(bottom).
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3. Efflux Cup
Reprint 142
In addition to the better precision of the differences among cups, a calibration chart relating drain time to
Shell, illustrated by results in table 1, kinematic viscosity should be constructed for each cup.
another indication of the superiority of
Shell cups over Zahn cups came from Figure 6 illustrates that drain times of Newtonian oils in the Shell
calibration studies in the NPIRI cup are much more sensitive than in the Zahn to changes in
Therefore, laboratories. The calibration was sample viscosity. Note also that the plot line for the Zahn does
conducted with standard Newtonian oils not go through zero, indicating that a correction factor is needed
the on a total of nine cups using the to account for turbulent flow [Euverard, 1950].
procedure described in ASTM Test
relationship Method D-4212. It should be pointed out that the only available standard fluids
are oils, most of which have viscosities giving drain times beyond
between drain Results indicated that essentially no the recommended range for a particular cup. A more serious
correction was required for the Shell problem is that their wetting characteristics are different from
time and cups tested (#2, #3, and #4). The those of typical liquid inks. Therefore, the relationship between
correction factor for the Zahn cups (#2 drain time and viscosity obtained with one type of fluid may not
viscosity and #3) averaged about 1.25 with a 100 be applicable to other types of fluids [McKelvie, 1970; General
cp oil and 1.45 with a 29 cp oil. The Electric, 1981].
obtained with correction factor for a #1 Zahn
exceeded 2.0 with the latter oil. Even when the efflux cup is being used for quality control of
one type of established formulations, a calibration procedure is necessary to
Figure 5 illustrates, in addition, that the detect differences in dimensions among cups, e.g. between the
fluid may not good agreement between the viscosities supplier’s and the customer’s, and also to follow changes in cup
calculated from the Shell and the actual performance due to dents, scratches or wear with use.
be applicable viscosities extended over temperatures
ranging from 20 to 30°C. On the other Influence of Surface Tension
to other types hand, the Zahn always gave calculated In order to determine the extent to which wetting characteristics
viscosities considerably less than the influence efflux cup results, experiments were conducted with
of fluids. true viscosities. Note also that the aqueous isopropanol (IPA) solutions varying in surface tension
agreement between the Shell and actual from 72 (pure water) to 21 (pure IPA) dynes per centimeter.
viscosities was further improved when Surface tension as a function of IPA concentration is plotted in
the sample was free of air bubbles. figure 7(a). Figure 7(b) shows that as the IPA concentration
increased the drain times on the Zahn decreased slightly while
The conversion from drain time to those on the Shell increased slightly.
viscosity was calculated by Patton’s
equations [1979], which assume that all
Figure 6. Calibration curves for #3 Zahn and #4 Shell cups
cups of the same type and model have
the same dimensions. To take into
using Cannon standard oils S-20, S-60, and S-200.
consideration that there are likely
Figure 5. Viscosity of Cannon standard oil S-20 on Zahn and Shell cups
as function of temperature.
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4. Efflux Cup
Reprint 142
Conversion of drain time to viscosity Influence of Temperature
using Patton’s equations revealed that ASTM Test Method D-4212 requires that the sample temperature
the Zahn, as seen in figure 7(c), gave a either be maintained at 25°C or be recorded to 0.1°C for
viscosity/IPA concentration plot very calibration and 1°C for general testing. The procedure suggests
similar to that of the surface tension plot construction of a temperature correction curve for each liquid by
. . . the Shell in figure 7(a). On the other hand, the plotting drain time as a function of sample temperature over the
Shell curve showed a maximum in expected temperature range. The instructions also specify
should be the viscosity at about 50% IPA. More immersion of the cup in the sample for at least five minutes to
importantly, the Shell curve shape reach sample temperature. For the more volatile inks,
efflux cup of matched that from the Brookfield considerable evaporation and settling could occur during this
viscometer. The Brookfield data are period.
choice when identical to those reported by Patton
[1979]. In the following experiments, one solvent-based and two water-
attempting to based commercial flexographic inks were diluted to a #2 Zahn
The results in figure 7 suggest that the cup reading of 21 ± 0.5 at 25°C (78°F) and then equilibrated at 20
characterize drain times on the Zahn cup are highly (68°F) and 30°C (86°F). Drain times were measured on the #2
sensitive to surface tension of the test Zahn and the #3 Shell at the three temperatures.
the flow fluid while those on the Shell are not. In
other words, the Shell should be the The results plotted in figure 8 indicate that, on both cups, the
properties of efflux cup of choice when attempting to change in drain time per degree Celsius varies widely from one
characterize the flow properties of a ink to another. For a specific ink, the drop in drain time with
a series of series of water-based inks or other increasing sample temperature is much greater on the Shell than
systems involving significant differences on the Zahn. These results are not surprising, considering that
water based in surface tension. the calibration curves in figure 6 had indicated a greater
sensitivity of the Shell drain times to changes in viscosity.
inks or other
In addition, data in figure 8 clearly illustrate the ability of the Shell
systems to differentiate among inks that exhibited essentially the same
drain time on the Zahn at 25°C. These results confirm those
involving reported by Bagnall [1982] and may explain the previously
significant
Figure 8. Drain times for three water or solvent based flexographic
differences in
inks at 20, 25, 30°C on Zahn #2 and Shell #3 cups.
surface
tension.
Figure 7. Viscosity of aqueous isopropanol
solutions varying in surface tension
measured on Zahn #2 and Shell #2 cups and
on Brookfield viscometer.
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5. Efflux Cup
Reprint 142
mentioned comment by Bates [1982] Figure 9 shows that all of the water based inks tested decreased
that inks having the same Zahn cup in viscosity as shear rates increased, in this case from 10 to 1000
reading performed differently on the sec-1. In limited studies at low shear rates, solvent-based inks
press. exhibited much the same shear thinning properties as did
The Shell cup aqueous inks.
Note also in figure 8 that the order in
is preferred which the inks are ranked for drain time Figure 9 also illustrates that some inks are more shear thinning
is different at 30°C than at 25°C. than others. Such tendencies can be detected only from
over the Zahn According to Stevko [1984], operating measurements from at least two different shear rates. On efflux
temperatures on a gravure press may cups, shear rate varies across the diameter of the capillary. An
cup because reach as high as 50°C (122°F). approximate shear rate can be calculated for a Newtonian fluid
Therefore, it may be advantageous to [Rodriquez, 1982]. The calculated shear rate for a 25 cp fluid on
certain design make efflux cup measurements at press the #3 Shell is approximately 300 s-1. Estimated shear rates on
temperatures and at those normally operating presses are well in excess of 1000 s-1.
features of recommended in test methods.
Irrespective, the sample temperature Because of the shear thinning nature of liquid inks, the equations
the Shell should always be reported along with relating drain time to viscosity no longer apply [McKelvie, 1970;
the test results. Patton, 1979; Mewis, 1980; Pierce, et al, 1982]. Therefore, test
results should be reported as drain times and not in terms of
make it more
Effect of Shear Rate kinematic viscosity, or if the density is measured, the dynamic
Since efflux cups are variations of viscosity.
reproducible, capillary viscometers, they have a same
basic restriction, namely that drain time Pigmented inks, besides having a complex rheology, present
less sensitive can be converted to viscosity only if the unique measuring problems including evaporation, pigment
test fluid is Newtonian. (Newtonian flocculation, settling of solids, foaming of water based inks,
to surface refers to a fluid whose viscosity does not structure buildup with time and probably wetting differences.
change with shear rate.) Results in our laboratory also indicate that ink viscoelasticity
tension of the varies with ink composition and degree of dilution and could
Although liquid inks are low in viscosity, influence drain time.
liquid, and the fact that they are pigmented polymer
solutions inherently indicates that they Conclusions
better able to are rarely Newtonian but are usually 1. A literature search and laboratory results clearly illustrate the
shear thinning. Confirming evidence complexity and limitations of efflux cup measurements and
differentiate was provided by measurements at a the careful control required to obtain correct data even on
variety of shear rates on the Brookfield simple Newtonian fluids.
among test viscometer and the Bohlin rheometer, 2. Of the four efflux cups studied, the ISO is most precise and the
both of which are rotational viscometers. Zahn is least precise.
fluids having 3. The Shell cup is preferred over the Zahn cup because certain
design features of the Shell make it more reproducible, less
different flow sensitive to surface tension of the liquid, and better able to
differentiate among test fluids having different flow properties.
properties. 4. Construction of calibration curves with standard oils is
necessary to detect differences among cups of the same type
and model and changes that occur with use.
5. The reporting of drain times must include the sample
temperature and the cup type and model. Useful information
can be derived by measuring drain times at room and at press
temperatures.
6. Liquid inks exhibit varying degrees of non-Newtonianism and,
for these reasons, drain times cannot be converted to
viscosity.
Figure 9. Viscosity of four water based
flexographic inks at 25°C on the Brookfield
viscometer at 10 s-1 and the Bohlin
rheometer at 100 s-1 and 1000 s-1.
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6. Efflux Cup
Reprint 142
References Rodriquez, R., Principles of Polymer Solutions, Second edition,
Standard Test Method D1200, “Viscosity of paints, varnishes and McGraw-Hill Book Company, New York, 1982.
lacquers by Ford viscosity cup,” Annual Book of ASTM
Standards, Vol. 06.01, American Society for Testing and Schramm, G., Introduction to Practical Viscometry, Haake Mess-
Materials, Philadelphia, 1952 (82). Technik GMBH-u.-CO, Karlsruhe, W. Germany, 1965.
Standard Test Method D4212, “Viscosity by dip-type cups,” Ibid. Stevko, P., “The effect of temperature on ink fountain solution
1982. viscosity,” Gravure Research Institute Report, No. M-273, New
York, 1984.
Bagnall, K., “Viscosity control of flexographic ink,” Boxboard
Containers, June 1983. VanWazer, J.R., J.W. Lyons, K.Y. Kim, and R.E. Colwell, Viscosity
and Flow Measurement, Wiley-Interscience, New York, 1963.
Bates, J.B., “Printing ink research — a vital resource,” American
Ink Maker, Vol. 60, No. 12, 1982, pp. 22, 24, 26, 30. Vomacka, F.N., “Shell and Zahn cups,” Gravure Technical
Association Bulletin, Vol. XIX, No. 2, 1968, pp. 122, 123, New
Ely, J.K., “Experiments to show ‘Seconds come first’ in waste- York.
preventing controls,” American Ink Maker, Vol. 58, No. 10, 1980,
pp. 46, 49, 50. Acknowledgement is made of the National Printing Ink Research
Institute for support of this work and permission to publish
Euverard, M.R., “The efflux type viscosity cup,” Scientific Edition results. Appreciation is also extended to F.J. Micale, J.M. Fetsko
of National Pain, Varnish, and Lacquer Association, Washington, andY.P. Lee for technical and editorial assistance; to Jo Evelyn
D.C., 1948. Gallagher for her skillful rheological measurements; to Bernadine
Dancho for preparing the figures; and to Arlene Toth for typing
“Evaluation of empirical viscosity measurements for varnishes the manuscript.
and resin solutions,” ASTM Bulletin, No. 169, October, 1950, pp.
dghr 4 t
67-70. = (1)
8LV
General Electric Company, “Instructions for Zahn viscometers,”
Publication No. 198 4541K23-001A, Lynn, MA, 1981.
Equations Describing Capillary Flow
International Standard 2431, “Paint and varnishes — The Hagen-Poiseuille equation (equation 1) describing liquid flow
Determination of flow time by use of flow cups,” International in classical fine-bore glass capillary viscometers such as the
Organization for Standardization, Geneva, 1980. Ostwald or Ubbelohde is usually applied to efflux cups [Patton,
1979]. The equation is based upon a parabolic flow profile of
Knorps, L., “Standardizing Zahn cups,” American Ink Maker, Vo. liquid through the capillary.
58, No. 8, 1980, pp. 20, 21, 50. where:
h = dynamic viscosity, centipoise (cp)
McKelvie, A.N., “An international flow cup,” Journal of Oil and d = density of fluid, µg/mm3
Color Chemists Assn., Vol. 53, 1970, pp. 92-120. g = gravitational acceleration, 9800 mm/sec2
h = effective hydrostatic head of liquid, related to difference in
Mewis, J., “Paints and printing inks,” Chapter 6, Rheometry: vertical height before and after the test, mm
Industrial Applications, edited by K. Walters, John Wiley & Sons, r = radius of capillary, mm
New York, 1980, pp. 281-338. L = length of capillary, mm
T = drain time, seconds (s)
Owczarwek, J., Introduction to Fluid Dynamics, International V = volume of flow during time t, mm3
Textbook Company, Scranton, PA, 1968.
Patton, T.C., Paint Flow and Pigment Dispersion, Second edition, If the density of the liquid is not known, the measurement yields
John Wiley & Sons, New York, 1979. the kinematic viscosity (v). The dynamic viscosity can be
obtained by multiplying the kinematic viscosity value by the
Pierce, P.E., and C.K. Schoff, “Rheological measurements,” Kirk- density.
Othmer: Encyclopedia of Chemical Technology, Vol. 20, Third
edition, John Wiley and Sons, New York, 1982, pp. 259-319. At the center of the capillary, the shear stress is zero, the shear
rate is zero, and the velocity is at maximum. At the capillary wall,
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7. Efflux Cup
Reprint 142
the shear stress and shear rate are at a maximum, and the For very accurate results, corrections must also be made for
velocity is assumed to be zero. Because the shear rate varies incomplete drainage, turbulence, and possible heat and surface
across the diameter of the capillary and the shear stress is tension effects [Pierce et al, 1982]. Corrections are minimized by
undefined, these capillaries should be limited to testing using a capillary with length at least 50 times the diameter
Newtonian fluids. Non-Newtonian fluids do not produce a [Schramm, 1965] and efflux times longer than 300 s [Pierce et al,
parabolic flow profile, which requires modification of the basic 1982].
equation [Rodriquez, 1982].
The correction terms for kinetic energy and end effects are
Two corrections are required for processingdata from capillary incorporated into the kinematic viscosity equation (equation 4)
viscometers: a kinetic energy correction (K.E.) and a Couette which is theoretically significant but usually shortened to
correction (C). Energy is expended as the height of liquid in the equation 5.
cup decreases reducing the potential energy of the system. The
Hagen-Poiseuille equation assumes that this energy is utilized v = kt - c/t (4)
completely in overcoming viscous resistance to flow. A portion,
however, is required to set the fluid into motion [Patton, 1979]. v = (t-c) (5)
This correction factor becomes extremely important for low
viscosity Newtonian fluids and approaches zero for high viscosity
fluids. The k and c values for each model Zahn, Shell, Ford and ISO
cups appear in the literature [Patton, 1979; ISO, 1980; Pierce et
Calculation of the actual viscosity requires inserting a kinetic al, 1982; ASTM, 1983]. The correct values for a specific cup can
energy correction term in the basic equation (equation 2). be calculated from calibration curves obtained with standard
Newtonian fluids [Euverard, 1950]
dghr4 t dV
= –
8 LT
(2)
8VL
(K.E. term)
The Couette correction relating to end effects is described by
equation 3 in which NDE is the Deborah number of the liquid.
The number is related to the ability of the liquid to recover after
being stressed [VanWazer, 1963]. NDE approaches zero for
Newtonian fluids and is much greater for clastic fluids.
L + N DE r
C = (3)
L
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