Navigation Links
CCNY team models sudden thickening of complex fluids
Date:1/16/2014

Because many materials are handled in industrial applications as suspensions, engineers need to understand how to predict their flow properties. However, they have been hard-pressed to understand DST and calculate when it will occur during processing. Since concentrated suspensions are found in everything from consumer products to cement, a range of industries stand to find better ways to manage suspensions.

For simple liquids, such as water or glycerin, resistance increases in proportion to the stirring speed. However, in complex fluids such as suspensions, emulsions and polymers the relationship is not proportional. Resistance increases either faster than the stirring speed shear thickening or slower shear thinning. DST occurs when resistance increases suddenly.

Research associates Ryohei Seto and Romain Mari and chemical engineering Professors Jeffrey Morris and Morton Denn set out to develop a model that would predict how resistance changes in relation to stirring speed. Their findings were reported in "Physical Review Letters" in November.

The model modifies the classical fluid mechanics approach to suspension behavior, in which liquid lubrication keeps particles from contact, to permit contact and to include forces resulting from friction as particles move past one another.

As friction increases two or more particles can act like a single entity with regard to the surrounding fluid. When concentrations of particles and the shear rate reach sufficient levels, the particles form temporary chains that can fill space. This causes jamming, which can make flow difficult or even impossible.

Using the model, the team was "able to accurately reproduce experimental observations of the steep viscosity versus shear rate curves and their evolution with packing friction, both of which are first for numerical simulations," Dr. Eric Brown, Yale University assistant professor of mechanical engineering and materials science, wrote in a commentary published in "Physics."

Future investigations will address moving beyond a simulation "that follows the mechanics of a finite number of particles in a cube to predicting the flow of concentrated suspensions in arbitrary geometries," Professor Denn noted. "A long-term goal is to be able to develop a 'continuum' description of concentrated suspensions in which the behavior is averaged over large numbers of particles."


'/>"/>

Contact: Ellis Simon
esimon@ccny.cuny.edu
212-650-6460
City College of New York
Source:Eurekalert  

Related biology news :

1. New method for estimating parameters may boost biological models
2. Screening horticultural imports: New models assess plant risk through better analysis
3. Rising heat at the beach threatens largest sea turtles, climate change models show
4. Symposium: Protein-Folding Diseases: Models & Mechanisms
5. 3-D tumor models improve drug discovery success rate
6. Autism Speaks and SAGE® Labs develop rat models for translational autism research
7. Molecular economics: New computer models calculate systems-wide costs of gene expression
8. ORNL researchers improve soil carbon cycling models
9. Climate models project increase in US wildfire risk
10. Improving the development of new cancer models using an advanced biomedical imaging method
11. Transplanted neural stem cells slows als onset and progression in mouse models
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
CCNY team models sudden thickening of complex fluids
(Date:3/15/2016)... ALBANY, New York , March 15, 2016 ... a new market report published by Transparency Market Research "Digital ... Growth, Trends and Forecast 2015 - 2023," the global digital ... at US$ 731.9 Mn in 2014 and is forecast to ... to 2023. Growth of micro, small and medium enterprises (MSMEs) ...
(Date:3/11/2016)... Germany , March 11, 2016 http://www.apimages.com ... - Cross reference: Picture is available at AP Images ( http://www.apimages.com ... from DERMALOG will be used to produce the new refugee identity ... other biometric innovations, at CeBIT in Hanover ... scanner from DERMALOG will be used to produce the new refugee ...
(Date:3/9/2016)... YORK , March 9, 2016 This ... and future states of the RNA Sequencing (RNA Seq) ... segments such as instruments, tools and reagents, data analysis, ... Analyze various segments of the RNA-Sequencing market such as ... services Identify the main factors affecting each segment and ...
Breaking Biology News(10 mins):
(Date:4/29/2016)... ... , ... The MIT bioLogic design team has won multiple A' Design ... can be applied to fabric and formed into living interfaces between body and environment. ... change. The team harvested Natto cells and applied them to fabric with custom 3D ...
(Date:4/29/2016)... ... April 29, 2016 , ... Summit for Stem Cell has received a $250,000 ... patient-specific stem cell therapy for the treatment of Parkinson’s disease. The Summit research project ... The Scripps Research Institute in San Diego, CA. , The aim of ...
(Date:4/28/2016)... ... April 28, 2016 , ... Connecticut ... innovative, growing companies, today announced the launch of VentureClash , a $5 ... , “VentureClash looks to attract the best early-stage companies here in ...
(Date:4/27/2016)... ... April 27, 2016 , ... Shimadzu Scientific Instruments ... Spring 2016 Marijuana Business Conference and Expo. Shimadzu’s high-performance instruments enable laboratories to ... more. Expo attendees can stop by booth 1021 to learn how Shimadzu’s instruments ...
Breaking Biology Technology: