	AllExperts > Aeronautical Engineering
	Search

About Paul Soderman
Expertise
Aeronautics, Fluid Mechanics, Aeroacoustics, Noise Control, Muffler Design, Wind Tunnel Research.... I know nothing about India - do not ask about schools, jobs, application requirements, career choices, etc. for India. Please, no text message verbiage; I prefer full words in full sentences. Thanks.

Experience
38 years as research engineer at NASA

Publications
AIAA, NASA

Education/Credentials
B.S. and M.S. Aeronautical Engineering - U. of Washington Graduate work Standford U.

Awards and Honors
AIAA Associate Fellow (American Institute of Aeronautics and Astronautics)

You are here: Experts > Science > Aerospace/Aviation > Aeronautical Engineering > Bypass Ratio

Aeronautical Engineering - Bypass Ratio

Expert: Paul Soderman - 10/27/2009

Question
What basis Bypass ratio has chosen for turbofan and turbojet engine? Bypass ratio varies from 5:1 to recent Ge 90 115B1 has 9.4:1. how to choose bypass ratio for various thrust range? what are the parameters involves in choosing bypass ratio?

Answer
A turbofan is a much quieter, more efficient engine than a turbojet. So you would like to achieve the highest bypass ratio possible. But there are constraints such as geometry, weight and drag. I assume, therefore, that engine developers have designed families of turbofans to fit different aircraft and different missions. For example, a small business jet with low wing could not support a high-bypass turbofan that would hit the ground. A large 747 transport could support a much larger engine. So aircraft and engines, including bypass ratio, are designed after a thorough system analysis involving all possible factors.

Add to this Answer Ask a Question