スートブロワ用超音速ノズル噴流の可視化計測とピトー圧分布

概要

論文の詳細を見る
A sootblower uses supersonic free jets obtained from nozzles to wash off deposit accumulated on the fireside surface of boiler tubes． To remove deposit effectively， it is desirable that the jet maintains high Pitot pressure even in the far downstream of the nozzle exit． In the present work， supersonic free jets obtained from three nozzles are investigated by visualizing the flow field with the schlieren method and also by measuring the Pitot pressure distributions along the jet center line． These nozzles have different shapes but have the same throat and exit areas；the exit Mach number calculated from the one-dimensional isentropic theory is 2．4． The experiments cover from over-to under-expansion pressure ratio． It is found that the complex wave pattern exists in the jets and this pattern depends strongly on the pressure ratio as well as on the nozzle shape． The decay process of the Pitot pressure in the downstream region is also clarified．These results will provide valuable information for the． design of the sootblower nozzles．
九州大学の論文
1999-12-30