I was recently watching this vox video and BBC documentary on the Concorde and supersonic travel. The fluid dynamics of air at mach speeds greater than 1 is a fascinating subject on its own accord.
Stagnation enthalpy is defined as the ‘Enthalpy of a fluid when it is brought to rest from velocity v isentropically’. Stagnation properties such as Stagnation enthalphy, pressure, temperature are often used to quantify the fast moving air around a flight moving at supersonic speeds.
“For very low Mach numbers, the density of the air is a constant. But as the Mach number increases into the supersonic regime, some of the energy associated with the motion of the object compresses the gas and changes the density from its static value….. As the Mach number increases into the low hypersonic regime, some of the energy of the flow excites the vibrational modes of the diatomic molecules.”
Imaging shock waves in a laboratory can be achieved through specialized tools, but NASA regularly posts images of shock waves around jets flying way up in the sky. How does one begin to visualize shock waves from an around an aircraft at several thousands of feet in the air. This post runs through a few techniques that are commonly employed
Vapor cones and condensation
Slowing down to Transonic speeds, a visible cloud of condensed water form around a fast moving aircraft or object known as a ‘vapor cone’.
In a previous post in this series titled ‘Keeping up with research‘, we talked about how it’s becoming increasingly difficult for scientists to identify quality research work as the number of research papers increased in their field. I think this is not a discussion that pertains only to research, but hints at a more fundamental problem in parsing information on the internet.
Frustrating google results
This blog post (along with these Reddit and ycombinator threads) describes how google search result relevance has plummeted to the extent where users end up adding something like “site:reddit.com” to the search term to yield better results.
Normalization refers to social processes through which ideas and actions come to be seen as ‘normal’ and become taken-for-granted or ‘natural’ in everyday life.
What’s more scarier than not getting relevant results? Search engines acting as a means to normalize thinking in society.
This psychology today series on the ‘internet brain‘ explores how our brain responds to the stimulus from the internet. Although this does not solve any of the above issues directly, it might help us identify patterns leading to manipulation.