pour over Coffee 手沖咖啡

Various gadgets for hand pouring,

- By shape geometry 

Cone: v60

Flat bottom: melitta

Basket: kalita wave, timemore b75, orea 

Homegrounds cone vs basket. Found that flat bottom baskets produce coffee with lower TDS than cone filters, all other factors (like pouring technique, water temperature, and grind size) being equal.(contradictory to James H)

Perfectdailygrind :The UC Davies and SCA study found that for light roast: flat-bottom basket yielded flavor attributes with more dried fruit, sweet, and floral flavor intensities, while the conical basket yielded more citrus, berry, and sour. 

Similarly, the basket shape affected the dark roast, with the flat bottom yielding more pronounced chocolate, cocoa, and woody flavors, and the conical yielding much more intense bitterness.

- By filter thickness:

Cafec: light roast to dark roast, thickness difference

Coffee adastra in depth analysis on coffee filter 

- By Material

Bleached vs unbleached

Bamboo and abaca (also known as Manila hemp) have the longest fibres of all of the common raw materials used to manufacture filter paper, and are consequently more porous (meaning more oils make their way into your cup). In contrast, eucalyptus pulp has the shortest fibres, and is the least porous of all the pulps used to manufacture filter paper.

Four rules from coffee ad astra

1. Avoid Bypass
2. Avoid Clogging
3. Achieve an Even Flow of Water Through the Coffee
4. Adjust your Brew Ratio to your Grind Size

Darcy's law

Perfectd

Yuki study on different shape of coffee bed by thermal imaging