Compact crossover diffuser?

[madrocketscientist]

I came across this diffuser design,

www.degruyter.com/view/j/tjj.ahead-of-print/tjj-2017-0021/tjj-2017-0021.xml

Has anyone had any experience with this style of diffuser? They claim over 80% thrust increase with the new compressor and diffuser, The old compressor/diffuser combo must have been pretty bad to get that sort of increase?

Opinions anyone?

Shannon

[racket]

Hi Shannon

Most of the thrust increase would have been from the larger compressor they squeezed into the casing , from both increased mass flow and a higher pressure ratio from a higher tip speed , simply modifying the diffuser would only give a limited amount of change .

Another Paper with a similar diffuser setup espace.library.uq.edu.au/data/UQ_121065/Ling_afmc_16_07.pdf?Expires=1511241389&Signature=W5y0emSZZM~3q6QWRTxsZ78Qeq~bv4VJi6cNVCVktYsP6Lrr-B2NWOq3PX-AjsPw9RLVWda98Zh32VdnV8yuKyJkv1gfcBI1XOtmxHXjoZ5aY9sLUTuSNB7L5VAj9HKMTFNMvbKXD6Mq1fAiAQPj45~~KPaj3d11j-HX7f3TTsaF0NDO8ofBDMXnLFjSH5iESWmJrZI0Gvt4YCxA7V-BzWBBbW5zg0jIHpBxqmGDSpP-rTeMcdwk8KHlUcrVPv00tWdXVEwl9X8QRQAlgHFG0NJZ6f~pkPXohzZ0nCy~wcy8FnHj9PYmAMOMWgU2WSLuH2SAeRZ1c5QUiz1v21pQoQ__&Key-Pair-Id=APKAJKNBJ4MJBJNC6NLQ

Cheers
John

[madrocketscientist]

That makes sense, the paper did say the were limited by the turbine, which indicates to me that the new compressor was then mismatched on the side of being too large for the turbine?

[racket]

Hi Shannon

Yeh , everything needs to match everything else otherwise theres "difficulties" , and we can't fudge the numbers , when you see an 80% improvement in thrust you know theres gotta be a "bigger hole in the front" :-)

Cheers
John