Talk:Roots blower/Archives/2021

Article should be moved

The proper name for this is Roots type compressor or even blower. Supercharging is just the best known application of Roots compressors, but the basic design is a different topic. We probably have an article about centrifugal pumps, turbines and impellers separate from the article on centrifugal superchargers, because that is just one application of the design. they are used in jet engines, liquid pumps, water jets, turbochargers, all kinds of things. A Roots compressor can be used for various applications, and in fact its first application was mechanical aspiration, or providing a very small pressure differential to scavenge exhaust gasses from 2 stoke engines, ensuring the fresh air flowed into the cylinder when the valve opened. This is NOT supercharging, the pressures are much lower and the power gain is negligible. it is simply mechanical aspiration, as used on the EMD and Detroit 2 stroke diesels. Later hot rodders found out that if the took a large blower designed to create a small pressure differential in a large engine like an 8-71 Detroit, and spun it a bit faster, they could create a supercharger out of it. Thus was born the Roots supercharger. It was still called the "Roots blower" because that is literally the part they were using, but it was now serving a different purpose: power adder. The classic was the 8/71, so called because it is designed to scavenge an 8 cylinder engine of 71 ci per cylinder, or 568ci total. Using it on a smaller engine, or increasing the revolutions created a significantly larger pressure differential. Even a 6/71 at high RPMs was sufficient. But the article is not about the Roots supercharger, it is about the Roots compressor and ALL of the jobs it does, including supercharger. Calling it the Roots type supercharger just confuses people who keep calling blown 2 stroke diesels "supercharged", cause after all, it says so right in the title of the page I linked to, right?

64.222.204.254 (talk) 20:37, 4 January 2021 (UTC)

Subway?

New York subway demonstration ThomasHarrisGrantsPass (talk) 16:23, 29 July 2021 (UTC)