bypass ratio


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bypass ratio

bypass ratio
The numerical ratio of mass airflow in the bypass duct (of a turbojet or a turbofan) to that of mass flow through the engine core. It is cold jet divided by hot jet.
References in periodicals archive ?
Finally, it was also noticed that the bypass ratio R had no influence on the results.
Having the bypass ratio it is necessary to compute the primary air flow and secondary air flow.
Consequently, noise reduction strategies are aimed at increasing bypass ratio to lower nozzle exit velocities and designing bypass and core flows to improve mixing with each other and the atmosphere.
So Wilde invented the wide-chord blade--for which he held the patent--and effectively the three-shaft, high bypass ratio engine.
As I detailed in these pages in May 2008, the PWIOOOG has a hub-mounted planetary gearing system that drives the fan at lower speeds, permitting up to 16 percent fuel savings, higher bypass ratios, and much lower fan noise.
LEAP-X has a bypass ratio of 12:1, compared to 5:1 for current engines.
He explained that airframe and wing "size dimension" was designed on the CSeries to optimize fully the PW1000G's 12:1 bypass ratio.
The Continental is powered by all-new twin AlliedSignal AS907 high bypass ratio turbofan engines, offering 6,500 pounds (28.
This new joint venture will focus on high bypass ratio geared turbofan technology.
The JT9D engine, on the other hand, needed a new case design to accommodate a large front-mounted fan with a bypass ratio of 5:1.
In simple terms, the GTF puts a gear system between the fan and the low-pressure compressor, which means the fan operates at a lower speed and enables the optimum bypass ratio to be increased to 12:1 or even a bit higher.
Two options are to increase the current state of the art bypass ratio level of turbofans (the ratio of air mass flow rate ducted by the fan around the engine core to the engine core airflow) or to eliminate the duct and use an open rotor (advanced prop fan).