Ideal intake runner termination design...
Ideal intake runner termination design...
(OP)
Just been reading a few articles, in particular:
Wave reflections from duct terminations
A. Selamet and Z. L. Ji
and
The acoustics of racing engine intake systems
M.F. Harrisona,*, A. Dunkleyb
now ive typically designed my intake runners to terminate (either within an airbox, or atmosphere) with a (relatively) small radiused bellmouth - for the obvious reason that the loss coefficient of the bellmouth provides better net flow capability.
however, reading about the acoustic boundary of a bellmouth (being possibly the worst re: low reflection coefficient) im concerned that by and large an effective bellmouth cacels out any acoustic tuning advantage i design into my intake runners.
harrisions article suggests that acoustic tuning is reasonably weak and contributes only in the lower rpm band, ineria ram being responsible for the majority of higher engine VE increases.
have i just dudded myself out of all the hours i spend calculating harmonic intake lengths??
discuss ;)
cheers
ed
Wave reflections from duct terminations
A. Selamet and Z. L. Ji
and
The acoustics of racing engine intake systems
M.F. Harrisona,*, A. Dunkleyb
now ive typically designed my intake runners to terminate (either within an airbox, or atmosphere) with a (relatively) small radiused bellmouth - for the obvious reason that the loss coefficient of the bellmouth provides better net flow capability.
however, reading about the acoustic boundary of a bellmouth (being possibly the worst re: low reflection coefficient) im concerned that by and large an effective bellmouth cacels out any acoustic tuning advantage i design into my intake runners.
harrisions article suggests that acoustic tuning is reasonably weak and contributes only in the lower rpm band, ineria ram being responsible for the majority of higher engine VE increases.
have i just dudded myself out of all the hours i spend calculating harmonic intake lengths??
discuss ;)
cheers
ed





RE: Ideal intake runner termination design...
RE: Ideal intake runner termination design...
RE: Ideal intake runner termination design...
http
but with further reading, perhaps such a lareg bell is a bad idea for acoustic tuning?
given the drop in reflection coefficient, would this bellmouth see losses in tuned performance, just have a significantly louder intake noise, or both?
cheers
ed
RE: Ideal intake runner termination design...