Airbrhing Propulsion -1 Airbrhing School o Arospc Enginring Propulsion Ovrviw w will b xmining numbr o irbrhing propulsion sysms rmjs, urbojs, urbons, urboprops Prormnc prmrs o compr hm, usul o din som prmrs h r rlvn o mking good propulsion sysm hlpul i hy don dpnd on ngin siz Spciic Thrus (ST) Spciic Ful Consumpion (SFC) Vrious ngin icincis, Thn w will us cycl nlysis o prdic prormnc s uncion o vrious dsign vribls From momnum consrvion Airbrhing Propulsion - School o Arospc J Enginring Engin Thrus p T sdy, uniorm, inviscid singl nozzl xhus srm Spciic Thrus (ST) m m m u m u p p A m 1 m u u p p A 1 u u p u p m A m For subsonic nozzls, p =p m u p T 1
Airbrhing Propulsion -3 School o Arospc Ovrll Enginring Eicincy How o chrcriz n ircr propulsion sysm bsd on how wll i producs h dsird oupu (hrus) givn h cos inpu (ul) Similr o cycl icincy, W ou Q H w cn din n Ovrll Eicincy or hrus producing ngins u o m h or urboshs W sh gol o ngin is o o produc sh powr m h hrus powr hing r rom ul Thrml School o Arospc nd Enginring Propulsiv Eicincis W cn lso brk down h ovrll procss o how n ngin producs hrus ino wo sps ul nrgy KE o proplln hrus work hrml icincy propulsiv icincy Thrml Eicincy or hrus producd using nozzls.g., simpl urboj 1 1 KE m m u m u KE h m h 1 h KE KE ou KE u u h in Airbrhing Propulsion -4
Airbrhing Propulsion -5 School o Thrml Arospc Enginring Eicincy or hrus producd using nozzl his is jus h cycl icincy or cycl h oupus kinic nrgy (nozzl) insd o work (urbin) KE h m h KE in nozzl xhus conins gs h is s (KE) bu lso ho (hrml nrgy), so h < 100% or urbosh ngins (nd urboprops whr mos o h oupu powr is o h driv sh) W sh h m h ul nrgy sh powr m h KE ou Airbrhing Propulsion -6 School Propulsiv o Arospc Enginring Eicincy How icin is kinic nrgy u p chng in producing hrus KE.g., simpl urboj 1 1 m KE u m m u m u p 1 u u p p A 1 u u i p =p 1 u u 1 m m p 1 u u 1 lil KE chng 1 s u u los o wsd KE or sic hrus cs 0 or u >> u =0 or u=0 p cn b >1 sinc ul is bing jcd oo Propulsiv Eicincy, p p 1. 1 0.8 0.6 0.4 0. =0.01 0 1 1.5.5 3 u /u 0 3
School Propulsiv o Arospc Enginring Eicincy For urboprop ngins, i is ypicl o rplc propulsiv icincy wih propllr icincy pru pr W sh i urboprop drivs signiicn hrus rom n ngin xhus nozzl (in ddiion o h propllr), hn somims usul o din n quivln sh powr u nozzl W sh quiv W, sh 1 hn pr W pr pr hrus rom propllr sh, quiv ol hrus powr Airbrhing Propulsion -7 School Eicincy o Arospc Enginring lions From our diniions or or urboprop n KE h p m h u m h n o h n o h p pr u KE o only nd o know o h icincis o ind h 3 rd Airbrhing Propulsion -8 4
Spciic School o Arospc Ful Enginring Consumpion, SFC How much dos givn moun o hrus cos in ul? Thrus Spciic Ful Consumpion (TSFC) lowr SFC grr rng or n ircr TSFC m SFC hs unis u o m h u TSFC o h lso rld o ST m m m i you know o you know TSFC ST whr rprsns ll h ul ddd Airbrhing Propulsion -9 Airbrhing Propulsion -10 Spciic School o Arospc Enginring Ful Consumpion For urbosh ngins, cn din sh powr bsd SFC m BSFC W his mric cn b pplid o ny yp o ulburning (combusion) ngin h producs sh powr (disls, sprk-igniion, ) brk is hold-ovr nm rom h wy h shpowr ws ypiclly sd on dynmomr whr h sh powr is bsorbd ( brk ) nd msurd sh 5
J Engin School o Arospc Enginring Prormnc Hisory How hs j ngin prormnc improvd sinc urboj wr irs dvlopd in h 1930 s Th ollowing inormion is dpd rom Progrss in Aro Engin Tchnology (1939-003) by Dilip. Blll (Univrsiy o Dyon) nd Josph Zlin (AFL) Airbrhing Propulsion -11 Srch School o Arospc Enginring or Highr Thrus 1903: 134 lb Wrigh Flyr 1939: 1,000 lb (~4450N) von Ohin/Whil 004 35,000 lb Miliry Engin 115,000 lb (GE90-115B) sd up o 10,000 lb ~8% o singl F-1 ngin in Surn V Airbrhing Propulsion -1 Adpd rom Blll nd Zlin 6
Spciic Thrus (N/kg/s) Thrus (kn) Gs Turbin School o Arospc Enginring Thrus Improvmns 600 500 400 300 00 100 Sinc 1939, sic hrus incrsd >110 or civil ngins nd 0 or miliry ngins Airbrhing Propulsion -13 Adpd rom Blll nd Zlin Spciic School o Arospc Enginring Thrus Improvmns 10,000 1000 Airbrhing Propulsion -14 Adpd rom Blll nd Zlin 7
003: 7 olls oyc Trn 003: 6.5 Miliry Engin 1939: 1. von Ohin/Whil 1903: 0.67 Wrigh Flyr School o Arospc Thrus/Wigh Enginring For comprison ~85 or Surn V F-1 Engin Airbrhing Propulsion -15 Adpd rom Blll nd Zlin h = K m h School o Arospc Enginring Eicincis r hrml Ovrll icincis 1903: 10% (Wrigh Flyr) 1939: 15% (von Ohin nd Whil) 003: 30% (Miliry Engin) 40% (Civil Engin) Modrn rongin hrml icincy pproching 50% Airbrhing Propulsion -16 Adpd rom Blll nd Zlin 8
SFC (kg/hr/n) Spciic School o Arospc Enginring Ful Consumpion 0.15 0.1 0.05 0 Tk-o hrus spciic ul consumpion is nr 0.34 (0.034) Airbrhing Propulsion -17 Adpd rom Blll nd Zlin School o Arospc Enginring Li on Wing Erly j ngins lsd <10 hours Modrn civil ngins cn sy on wing or >10,000 hours Miliry ngins ls up o 800 hours Airbrhing Propulsion -18 Adpd rom Blll nd Zlin 9
School o Arospc Enginring libiliy Airbrhing Propulsion -19 Adpd rom Blll nd Zlin 10