3D-Euler flow analysis of fanjet engine and turbine powered simulator with experimental comparison in transonic speed

Transonic 3-0 Eu le r f l o w a n a l y s i s code f o r f a n j e t engine and Turbine Powered Simulator (T. P. S. 1 wind tunnel t e s t i n g was developed u t i l i z i n g MacCormack's scheme i n f i n i t e volume form. The purpose i s t o val idate the T.P.S. t es t i ng method a t NAL Transonic Wind Tunnel developed f o r the Exper imental STOL Plane 'Aska' and other t ranspor t a i r c r a f t t e s t i n g s as w e l l a s t o analyze the f a n j e t engine f low f i e l d . Cmparison of the cmputat ions wi th an experimental data f o r a pre l im ina ry ax i smmet r i c T.P.S. conf igurat ion was made. The pressure d i s t r i b u t i o n s on the i n l e t cowl and co re je t cowl surfaces show an excel lent agreement. The e f f e c t s o f t he engine c o n d i t i o n d i f f e rence between the rea l fanje t engine and T. P. S. simulation: j e t temperature and massflux r e l a t i o n s . were analyzed. The r e s u l t shows l i t t l e di f ferences in the external flow f i e l d surrounding the exhaust-jet plume. 3-0 f low analysis was also made and i t revealed angle o f a t t a c k e f f e c t s i n the i n l e t f l ow f i e l d and exhaust-jet plume. A pa i r of longi tudinal vortex was observed in t h e shear l a y e r between the j e t and the external flows. 1 . In t roduct ion I n l e t aerodynamics and f low analys is around a f a n j e t engine is increas ing i t s importance as high bypass r a t i o turbo-fanjet engine wi th large fan diameter became i n use for the advanced transport . The design of engine nacel le requires the de ta i l ed f low analysis. In teract ion of engine f l o w f i e l d w i t h main wing is a lso of s ign i f i can t concern t o avoid d e t e r i o r a t i o n of aerodynamic cha rac te r i s t i cs of the wing. Flowthrough and e jector nacelles have been used i n the past. Experimental f low analyses on them were made by Baglev-Kurn ' , Langley ' and Crook a for example. Recently. Turbine-Poweied Simulator(T. P. S. ) is u t i l i z e d in the wind tunne l t o account f o r more accurate engine ef fects on the aerodynamic model. The junior author, K.Asai e t a i . developed t e s t i n g method of T.P.S. i n NAL 2m X2m Transonic Wind Tunnel. A prel iminary a x i s m e t r i c T. P. S. conf igurat ion experiment was done t o establ ish the tes t i ng technique. Then the method was applied t o the test of the NAL Experimental STOL Plane 'Aska' which adopts the Upper Surface Blowing ( US8 ) as the high l i f t device '. Although T. P. S. s imulat ion i s considered most excellent aerodynamic s imulat ion method today, there ex is t yet some dif ferences between the T.P.S. and the rea l fanje t engine ; i . e . , (I) T.P.S. c o r e j e t temperature i s co ld whi le the r e a l engine exhausts hot combustion gas and (2) dif ference in the r e l a t i o n o f mass f l ow r a t i o ( M.F.R.) and bypass * Branch Chief. A i rcraf t Aerodynamics Division. * * Research Scient ist , A i r c ra f t Aerodynamics Division, t Graduate student ( present ly UNISYS JAPAN ) Associate Fellow. A I A A .