bypass ratio


Definition of bypass ratio 

: the ratio in an aircraft engine (such as a turbofan) of the amount of airflow that is bypassed around the engine's core to the amount that passes through the core The bypass ratio is the amount of the air that passes through the fan—known as “cold thrust”—compared with the amount that passes through the core, or combustion chamber—“hot thrust.” Typically, the higher an engine's bypass ratio, the better its fuel efficiency.— David Noland, Air & Space Smithsonian, February/March 2008

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First Known Use of bypass ratio

1961, in the meaning defined above

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bypass condenser


bypass ratio

bypass valve



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The first known use of bypass ratio was in 1961

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to clear from alleged fault or guilt

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