The bypass ratio has been increased over previous variants by suitable adjustments to the core flow.
Other cycle parameters are a bypass ratio 5.3 and airflow of 240 lb/s.
This low specific thrust is usually achieved with a high bypass ratio.
As a result, fans have grown steadily larger, to increase the bypass ratio.
It had a bypass ratio of 6.2 and a pressure ratio of 21.0.
This configuration had a 20:1 bypass ratio and was expected to provide a thrust of 30,000 lbf.
Reducing core flow also increases bypass ratio (5:1, or more, is now common).
Consider a mixed turbofan with a fixed bypass ratio and airflow.
Overall pressure ratio is 28.0, with a bypass ratio of 4.66.
Overall pressure ratio is 30.4, with a bypass ratio of 5.15.