Why guinness bubbles go down

Previous research suggests that this phenomena is due the small size of the bubbles in these beers and the presence of a circulatory current, directed downwards near the side of the wall and upwards in the interior of the glass.

The mechanism by which such a circulation is established and the conditions under which it will occur has not been clarified. In this paper, we demonstrate using simulations and experiment that the flow in a glass of stout depends on the shape of the glass.

If it narrows downwards as the traditional stout glass, the pint, does , the flow is directed downwards near the wall and upwards in the interior and sinking bubbles will be observed.

If the container widens downwards, the flow is opposite to that described above and only rising bubbles will be seen. More from Other Physics Topics.

Use this form if you have come across a typo, inaccuracy or would like to send an edit request for the content on this page. For general inquiries, please use our contact form. For general feedback, use the public comments section below please adhere to guidelines. Your feedback is important to us. However, we do not guarantee individual replies due to the high volume of messages. Your email address is used only to let the recipient know who sent the email.

Neither your address nor the recipient's address will be used for any other purpose. The information you enter will appear in your e-mail message and is not retained by Phys. You can unsubscribe at any time and we'll never share your details to third parties. More information Privacy policy.

This site uses cookies to assist with navigation, analyse your use of our services, collect data for ads personalisation and provide content from third parties.

By using our site, you acknowledge that you have read and understand our Privacy Policy and Terms of Use. Share Twit Share Email.

Home Physics General Physics. Simulations of the elongated vortices in left a pint glass, where bubbles sink near the glass wall, and right an anti-pint glass, where bubbles rise near the wall. Image credit: E. Benilov, et al. More information: E. This document is subject to copyright.

Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Synthesizing nanomaterials from nature's blueprints 11 hours ago. These bubbles float upward with some relative force.

Bubbles from the top are then pulled back down around the column in order to fill the low bubble density areas along the sides and bottom. Think of this as watching Titanic in reverse. In this case, the Titanic is the column of nitrogen bubbles moving upward. As the Titanic sinks into the chilly North Atlantic, it created suction behind it. This is what pulls Jack under water Rose had on a life vest. In our case, nitrogen bubbles, which travel along the sides of the glass, are pulled to the bottom of the glass along the sides of the glass.

In the figure, the sinking bubbles are found in the yellow and green areas. But in his paper, Dr. He also drinks beer occasionally. Search this website. Search for:. Store Subscribe. When we saw the bubbles really were going down, I was immeasurably happy.

We then filmed it as a colleague pointed out that people might have said all we did was turn the photos upside down. But it's true. The circulation cells in the glass provide the same effect like you see in a tornado. A spokesman for the RSC said: "Guinness is good for this experiment as the bubbles are small, due to being released at high pressure by the widget and therefore easily pushed around. The gas in the bubbles is also important. In lager beers, the gas is carbon dioxide which is more easily dissolved into the liquid.

The gas in Guinness bubbles is nitrogen - not so easily dissolved and therefore not prone to grow larger. We're pleased to have finally solved this mystery in time for St Patrick's Day when many people will no doubt be enjoying a pint or two.