Featured Research

from universities, journals, and other organizations

Ketchup turns somersaults

Date:
March 7, 2013
Source:
Technische Universitaet Muenchen
Summary:
Blood, paint or ketchup are complex liquids composed of several different components. For the construction of pumps, or the improvement of technical processes scientists and engineers need description models. They make the special properties of such liquids predictable. Researchers have now developed such a model.

Why ketchup turns somersaults - the extraordinary behavior of complex fluids.
Credit: Markus Harasim / TUM

Blood, paint or ketchup are complex liquids composed of several different components. For the construction of pumps, or the improvement of technical processes scientists and engineers need description models. They make the special properties of such liquids predictable. Researchers at the Technische Universitaet Muenchen (TUM) and the Federal Institute of Technology Zurich (ETHZ) have developed such a model. In the current issue of the journal Physical Review Letters they present it.

Related Articles


The unusual behavior of complex fluids is part of our daily life: cake dough climbs up the stirring bar, ketchup becomes liquid when you shake it. Also technology uses such phenomena: if we add a small amount of long-chained polymer molecules, a pipeline can transport more oil. The polymers reduce the flow resistance. But up to now the origin of these effects was unclear. The engineers had to rely on estimates and lengthy trials.

A team of physicists led by Professor Andreas Bausch, Chair of Cellular Biophysics at TUM now developed a numerical model of such liquids. Experimental heart of the work are a fine flow channel and a micro-camera. Like the camera looking down at the pit lane of Formula 1 races, the scientists monitored the movements of individual polymer molecules in the flow.

From their observations they conducted a theoretical model for the motion of rigid molecules different from the current. In addition, they were able also to provide for colleagues suspected of movement patterns experimental confirmation.

Challenging for theory and experiment

"Due to the incredibly large number of degrees of freedom the study and description of the motion of polymers is a big challenge," says Markus Harasim, one of the two main authors. Even a simple system of water and polymer shows the effects of complex fluids. In order to make the long molecules visible, the physicists marked the polymers with a fluorescent dye. This allowed them to study the movements under various conditions.

To their surprise the mathematical modeling showed, that even the simple model of a stiff rod was suitable as a starting point. Then the researchers refined the model by taking into account the thermal motion, the flexibility of the molecule and the higher flow resistance of a curved polymer. "Since we now know the microscopic mechanisms, we can extend the model to more complex geometries and flows. And thanks to our experimental set-up we should be able to verify our theories," says co-author Bernhard Wunderlich, who is a well known rapper in the hip-hop band "Blumentopf" in his off time.

The work was funded by the German Research Foundation Center's research and the Cluster of Excellence Nanosystems Initiative Munich (NIM).


Story Source:

The above story is based on materials provided by Technische Universitaet Muenchen. Note: Materials may be edited for content and length.


Journal Reference:

  1. Markus Harasim, Bernhard Wunderlich, Orit Peleg, Martin Krφger, Andreas R. Bausch. Direct Observation of the Dynamics of Semiflexible Polymers in Shear Flow. Physical Review Letters, 2013; 110 (10) DOI: 10.1103/PhysRevLett.110.108302

Cite This Page:

Technische Universitaet Muenchen. "Ketchup turns somersaults." ScienceDaily. ScienceDaily, 7 March 2013. <www.sciencedaily.com/releases/2013/03/130307124657.htm>.
Technische Universitaet Muenchen. (2013, March 7). Ketchup turns somersaults. ScienceDaily. Retrieved January 31, 2015 from www.sciencedaily.com/releases/2013/03/130307124657.htm
Technische Universitaet Muenchen. "Ketchup turns somersaults." ScienceDaily. www.sciencedaily.com/releases/2013/03/130307124657.htm (accessed January 31, 2015).

Share This


More From ScienceDaily



More Matter & Energy News

Saturday, January 31, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Nanoscale Sensor Could Help Wine Producers and Clinical Scientists

Nanoscale Sensor Could Help Wine Producers and Clinical Scientists

Reuters - Innovations Video Online (Jan. 30, 2015) — A nanosensor that mimics the oral effects and sensations of drinking wine has been developed by Danish and Portuguese researchers. Jim Drury saw it in operation. Video provided by Reuters
Powered by NewsLook.com
Tesla 'Insane Mode' Gives Unsuspecting Passengers the Ride of Their Life

Tesla 'Insane Mode' Gives Unsuspecting Passengers the Ride of Their Life

RightThisMinute (Jan. 29, 2015) — If your car has an "Insane Mode" then you know it&apos;s fast. Well, these unsuspecting passengers were in for one insane ride when they hit the button. Tesla cars are awesome. Video provided by RightThisMinute
Powered by NewsLook.com
Now Bill Gates Is 'Concerned' About Artificial Intelligence

Now Bill Gates Is 'Concerned' About Artificial Intelligence

Newsy (Jan. 29, 2015) — Bill Gates joins the list of tech moguls scared of super-intelligent machines. He says more people should be concerned, but why? Video provided by Newsy
Powered by NewsLook.com
Senate Passes Bill for Keystone XL Pipeline

Senate Passes Bill for Keystone XL Pipeline

AP (Jan. 29, 2015) — The Republican-controlled Senate has passed a bipartisan bill approving construction of the Keystone XL oil pipeline. (Jan. 29) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins