Talk:Propeller theory

Feedback from New Page Review process
I left the following feedback for the creator/future reviewers while reviewing this article: Hello, Thank you for creating a new article. Kindly see the talk pages of similar articles, and add relevant "wikiproject banners" on Talk:Propeller theory. Also, kindly see similar articles, and add relevant categories to the article..

—usernamekiran (talk) 12:34, 8 July 2020 (UTC)

Explanation
Re: A Proposal to hive off part of the Propeller page

I felt that the mathematical detail in the "Propeller theory" paragraph of the Propeller page lay unhappily with the remainder of the page. So I retained a simpler summary, while the bulk of the maths was shifted to this new page, Propeller theory. As it was, one might read through all the figures and still have no idea about the approximate real-world values for slip on, say, a small fast-spinning outboard-motor propeller, or a large slow-turning oil tanker prop. My thanks to other editors who have helped polish up the new site, and to User:BD2412 for the comment, "That sounds reasonable. Arrivisto (talk) 09:57, 9 July 2020 (UTC)

Page is incomplete and contains error
This is not a well organized page in my opinion. However, my main concern is an error dL and dD. The second velocity term is missing the angular velocity N (actually the square of N).

Without prior knowledge many of the parameters are obscure at best. What are a, a', b? Are any of them a function of something else, like b, which appears to be chord length.

The graphic may be helpful to learn the names of parts of a propeller, but is of no value for deciphering how the equations apply to the propeller. What are phi and beta and how do they relate to alpha?

In the section Forces acting on a foil it correctly states that lift and drag are perpendicular and parallel to the flow respectively. In the section Propeller thrust Equation it incorrectly states that the differential lift, dL, is the force perpendicular to the surface.

In one place tangent(beta) is given as the ratio of the drag and lift coefficients. Lower down in the article it states that beta is the ratio of drag and lift coefficients. Which one is correct?

The references are of little value. One is to a company that makes propellers but is not helpful in understanding theory. The other is to an article about computational software. There should be some reference or references that aid in understanding the theory. As an example, a quick search turned up http://www.aerodynamics4students.com/propulsion/blade-element-propeller-theory.php.

Overall, the article needs considerable corrective work in order to be useful. Ihleslie (talk) 15:40, 5 June 2021 (UTC)