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AERODYNAMIC SUMMARY SHEET Prepared by Vladimir SMOLKO 1 Nomenclature Subscripts A Aspect Ratio n Load Factor (g’s) Γ Circulation (Ft2/sec) A Aileron S Static Flow Cross Section Area (Ft2) P pressure (psf) γ Flight Path Angle (Deg) ac aerodynamic center T Total a Speed of Sound (Ft/Sec) Roll Rate Body Axis (Rad/sec) Specific Heat Ratio CP/CV am ambient True Acceleration (Ft/Sec2) Time to Oscillate One Cycle (sec) ∆ Increment Notation C calibrated Tropopause Lift Curve Slope (1/Deg) Q Pitch Rate Body Axis (Rad/sec) δ Pressure Ratio P/P0 Compressible Thrust b Wing Span q Dynamic Pressure (Psf) Boundary Layer Thickness (Ft) Chord t tail C Coefficient R Yaw Rate Body Axis (Rad/sec) Control Surface Deflection (Deg) CG Center of gravity W Wind c Wing Mean Aerodynamic Chord (Ft) Gas Constant ε Temperature Probe Recovery Factor D Drag Wing D Drag Radius (Ft) Atmospheric Eddy Viscosity DP Positive Drag Y Side Force e wing efficiency factor RN Reynolds Number Downwash Angle (Deg) d Damping F Thrust (Lbs) R/C Ratio of Climb (Ft/Min) ζ Damping Ratio E Elevator Force (Lbs) S Wing Area (Ft2) θ Temperature Ratio T/T0 e Equivalent FC Compressibility Factor Take Off Distance (Ft) Pitch Attitude Earth Axis System f Friction G(s) Forward Loop Transfer Function T Thrust (Lbs) Λ Sweep Angle (Deg) G Gross g Acceleration of gravity (Ft/Sec2) Temperature (0R) λ Taper Ratio Ground H Altitude Geopotential (Ft) TSFC Thrust Specific Fuel Consumption µ Friction coefficient I Indicated H(s) Feedback Transfer Function t Time (sec) Viscosity (Lb·Sec/Ft2) i Incidence K Gain V Velocity (Ft/Sec) ν Cinematic Viscosity (Ft2/Sec) L Lift L Lift (Lbs) Volume (Ft3) ρ Mass Air density (slug/Ft3) l Roll Ln Natural logarithm W Gross Weight (Lbs) σ Density ratio ρ/ρ0 m Pitch L’ Rolling Moment (Ft·Lbs) WA Mass Flow Air (Lbs/Sec) Side Angle (Deg) n Yaw L Characteristic Length (Ft) Wf Fuel Flow(Lbs/Hr) τ Time Constant (Sec) North M Pitching Moment (Ft·Lbs) w Specific Weight ф Bank Angle (Earth Axis System) Natural M Mach Number Y Side Force (Lbs) Runway Gradient (deg) 0 Sea level m mass (slugs) α Angle of Attack (Deg) ψ Yaw Angle (Earth Axis System) p Pressure N Yawing Moment (Ft·Lbs) β Angle of Sideslip (Deg) ω Frequency (Rad/sec) R Rudder ATMOSPHERE Pressure Density Alt Ft PSF δ SLUG/FT3 σ TEMP 0R 0 2,116.22 1.0000 .002377 1.0000 518.67 10,000 1,455.32 .6877 .001766 .7385 483.01 20,000 972.48 .4595 .001266 .6328 447.35 30,000 628.43 .2970 .000689 .3741 411.69 40,000 391.69 .1851 .000585 .2452 389.97 50,000 242.22 .1145 .000362 .1522 389.97 THERMODYNAMICS P=Pressure (PSF) V= Volume (Ft3/Slug) T=Temp (0R) RTPV = TgRTP ρρ 1716== V1=ρ Isentropic (reversible Adiabatic) γ = 2 1 12 V V PP 1 1 2 12 − = γ γ T T PP γ 1 2 1 12 = P P VV 1 1 2 1 12 − = γ T T VV γ γ 1 1 2 12 − = P P TT 1 2 1 12 − = γ V V TT For Air Atmospheric Temperature, below 50,000Ft FLbBTUCP 0/240. ⋅= FLbBTUC V 0/1715. ⋅= 40.1== VP CCγ ⋅ ⋅= T T P P 0 0 002327.0ρ w=ρg Lbs/Ft3 Speed of sound, Standard Day sea level a=1116.45Ft/sec )()(04.29)/()(02.49 00 KnotsRTSecFtRTa ⋅=⋅= BOUNDARY LAYER Flat Plate Laminar Flow NR l2.5 =δ Turbulent Flow 2.0 37.0 NR l =δ νµ ρ lVlV R TTN == 72.198 102697.2 8 + ⋅ = − T TT µ Standard Day sea level µ=3.7372·10-5 Lb·Sec/Ft2 ν=µ/ρ AERODYNAMICS BASIC LAWS Continuity Equation Momentum Equation tConsAV tan=ρ VmF ∆= ⋅ Bernoullis Equation Incompressible Compressible 2 2V PPT ρ += 211 2VPP T T +⋅ − =⋅ − ργ γ ργ γ AERODYNAMIC COEFFICIENTS qS L CL = qS D CD = cqS M CM = q P CP ∆ = qSb L Cl ' = qSb N CN = qS Y CY = qS T CT = GEOMETRY For Straight Tapered Surface Aspect Ratio S b A 2 = + ++ ⋅⋅= 1 1 3 2 2 λ λλ tCc Taper Ratio r t C C =λ + + ⋅= λ λ 1 21 6 b v Area ( ) 2 rt CCb S +⋅ = Altitude (Ft) Sea Level->36,089 A1=6.87536·10 -6 Pressure ratio δ=(1-A1H) 5.2563 H=145,448(1-δ0.19026) Density ratio σ=(1-A1H) 4.2563 H=145,448(1-σ0.23496) Temperature ratio θ=(1-A1H) H=145,448(1-θ) Altitude (Ft) 36,089->65,617 A2=4.80634 10 -5 65,617->104,987; A3=3.17176 10 -5 Pressure ratio δ=0.22336·e-A2·(H-36,089) δ=A3θ -34.1632 Density ratio σ=0.29708·e-A2·(H-36,089) σ=A3θ -34.1632 Temperature ratio θ=0.75187 θ=0.68246+1.05778·10-6 Airspeed/Mach/Dynamic Pressure/Total Conditions Dynamic Pressure )( 295 )( 1481 2 2 2 2 PSF KtsV M V q eT =⋅⋅== δ ρ Impact Pressure (Pitot-Static Measure) ++++=⋅=−= ... 80404 1;; 842 MMM FFqqPPq CCCSTC ( )[ ] SC PMq ⋅−⋅+= 12.01 5.32 Mach No − + − ⋅+⋅= 111 5.661 )( 2.015 286.0 5.3 2 0 KtsV P P M C Indicated Airspeed VI = VC + ∆Vpitot Static Source Error Calibrated Airspeed )(1 _ 11.1479 28571.0 0 Knots P PP V ST c − +⋅= Equivalent Airspeed )(11174.32 28571.0 Knots P PP PV S ST Se − − +⋅= True Airspeed a V M V V TeT == σ Total condition M < 1.0 γ=1.4 ( )22 2.01 2 1 1 MTMTTT ⋅+⋅= ⋅ − +⋅= εε γ ( ) 5.22 1 1 2 2.01 2 1 1 MMT ⋅+⋅= ⋅ − +⋅= − ρ γ ρρ γ ( ) 5.32 1 2 2.01 2 1 1 MPMPPT ⋅+⋅= ⋅ − +⋅= −γ γ γ Total condition M = 1.0 γ=1.4 528.0634.0833.0 === TTT P P T T ρ ρ Conversion Factors bars x 75.006 =CM Hg 00C Ft/sec x0.6818 =MPH BTU x 778.169 =Ft·Lbs Ft/sec x1.0973 =Km/Hr BTU/sec x1054.118x =Watts Ft·Lbs/Sec x1.1818·10-3 =H.P. CM Hg x 27.845 =Lbs/Ft2 Fluid Oz x29.6 =Cu CM Ft3 x 28.317 =Liter Gals Imp x1.201 =U.S. Gal dynes x2.248·10-6 =Lbs Kilogram x2.205 =Lbs Ergs x7.376·10-8 =Ft·Lbs Knots x1.688 =Ft/sec Ft x0.3048 =Meters Liters x0.2642 =U.S. Gals Ft/sec x0.5925 =Kts Rad x57.29 =Deg Constants Weigths Lbs/Gal At 0C g=32.174 Ft/Sec2 JP-4 6.55 20 R= 63.35 Ft·Lbs/LB0R Water 8.345 4 γ=1.4 AERODYNAMIC SUMMARY SHEET Prepared by Vladimir SMOLKO 2 LONGITUDINAL STABILITY LATERAL DIRECTIONAL STABILITY AXIS TRANSFORMATION Component Along Earth Axes X Y Z XE YE ZE XB ψθ coscos ⋅ ψθ sin⋅cos θsin− YB ψφψθφ sinsinsin ⋅−⋅⋅ coscos ψφψθφ coscos ⋅+⋅⋅ sinsinsin θφ cos⋅sin Body Axes Component ZB ψφψθφ sinsinsin ⋅+⋅⋅ coscos ψφψθφ coscos ⋅−⋅⋅ sinsinsin θφ coscos ⋅ Angular Velocity relations θψφ sinP ⋅−= && θφθφψ seccossec ⋅⋅+⋅⋅= RsinQ& θφψφθ coscos ⋅⋅+⋅= sinQ & φφθ sinRQ ⋅−⋅= cos& θφψφθ coscos ⋅⋅+⋅−= && sinR θφθφφ tancostan ⋅⋅+⋅⋅+= RsinQP& Lateral –Directional Axis System Small perturbation Assumption Lateral-Directional Equation of motion RArp RA YYrYpYYgrUv δδβθφ δδβ ++++∆+⋅=+ 00 cos& Ft/Sec2 ( ) RArpxxxz RA LLrLpLLrIIp δδβ δδβ ++++∆=⋅− && Rad/Sec2 ( ) RArpzzxz RA NNrNpNNpIIr δδβ δδβ ++++∆=⋅− && Rad/Sec2 Lateral-Directional Dimensional Stability Derivatives Side force due to sideslip Roll moment due to aileron deflection )sec( 2−⋅= Ft m qSC Y Yβ β )( 12 −− ⋅= DegSec I qSC L xx l A A δ δ Side force due to roll rate Roll moment due to rudder deflection )sec( 2 1 0 −⋅= Ft mU qSbC Y pY p )( 12 −− ⋅= DegSec I qSC L xx l R R δ δSide force due to rate of yaw Aircraft’s directional stability )sec( 2 1 0 −⋅= Ft mU qSbC Y r Y r )( 2−= Sec I qSC N zz nβ β Side force due to aileron deflection )sec( 12 −− ⋅⋅= DegFt m qSC Y A A δ δ )( 2−= Sec I qSC N zz n T Tβ β Side force due to rudder deflection Yaw moment due to roll rate )sec( 12 −− ⋅⋅= DegFt m qSC Y R R δ δ )( 2 1 0 2 −= Sec UI CqSb N zz n p p ‘Dihedral effect’, lateral stability ‘Yaw damping’ )( 2−= Sec I qSbC L xx lβ β )( 2 1 0 2 −= Sec UI CqSb N zz n r r ‘Roll damping’ Yaw moment due to aileron deflection )( 2 1 0 2 −= Sec UI CqSb L xx l p p )( 12 −− ⋅= DegSec I qSbC N zz n A A δ δ Roll moment due to yaw rate Yaw moment due to rudder deflection )( 2 1 0 2 −= Sec UI CqSb L xx l r r )( 12 −− ⋅= DegSec I qSbC N zz n R R δ δ Perturbation Equation vVV += 0 0Uv=∆β pPP += 0 0Uv& & =∆β rRR += 0 ψψψ ∆+= 0 φφ ∆= XE, YE - Earth Axes XSo, YSo – Initial Stability Axes XS YS – Disturbed Stability Axes βo=0 Longitudinal Axis System Small perturbation Assumption Longitudinal Equation of motion ETu Eu XXuXuXgu δαθθ δα +∆+++⋅−= 0cos& Ft/Sec2 Equ E ZqZZZuZsingqUw δααθθ δαα ++∆+∆++⋅−=− && &00 Ft/Sec2 EqTTu Eu MqMMMMuMuMq δααα δαα α ++∆+∆+∆++= && & Rad/Sec2 Longitudinal Dimensional Stability Derivatives ‘Speed damping’ derivative Z-force due to Elevator )(sec )2( 1 0 0 − +− = mU CCqS X DD u u )( 12 −− ⋅⋅ − = DegSecFt m qSC Z E E Lδ δ Thrust changes due to speed ‘Speed effect stability’ )(sec )2( 1 0 − + = mU CCqS X XuX u TT T ( ) )( 2 11 0 0 −− ⋅ +− = SecFt UI CCcqS M YY mm u u X-force due to AoA M due to Thrust / Speed changes )sec( )( 20 −⋅ −− = Ft m CCqS X LDα α ( ) )( 2 11 0 −− ⋅ +− = SecFt UI CCcqS M YY mm T TuT u ‘Trim drag’ ‘AoA stability’ )sec( 12 −− ⋅⋅ − = DegFt m qSC X E E Dδ δ )( 2−= Sec I CcqS M YY mα α Z-force due to forward speed M due to Thrust / AoA changes )(sec )2( 1 0 0 − +− = mU CCqS Z LL u u )( 2−= Sec I CcqS M YY m T Tα α Z-force due to AoA ‘Downwash lag’ derivative )sec( )( 20 −⋅ +− = Ft m CCqS Z DLα α )( 2 1 0 2 −= Sec UI CcqS M YY mα α & & Z-force due to AoA rate ‘Pitch damping’ )sec( 2 1 0 −⋅ − = Ft mU qSC Z L εα α & & )( 2 1 0 2 −= Sec UI CcqS M YY m q q Z-force due to rate of pitch Elevator control effectiveness )sec( 2 1 0 −⋅ − = Ft mU qSC Z qL q ε )( 2−= Sec I CcqS M YY m E E δ δ Perturbation Equation uUU += 0 0Uw=∆α wWW += 0 0Uw&& =∆α qQQ += 0 ααα ∆+= 0 θθθ ∆+= 0 αθγ ∆−= XE, ZE - Earth Axes XSo, ZSo – Initial Stability Axes XS ZS – Disturbed Stability Axes Earth to body Axis Yaw-Pitch-Roll Sequence Vector Transformation Matrix Earth to body Axes (Yaw-Pitch-Roll Sequence) Component Along Wind Axes X Y Z XW YW ZW XB βα coscos ⋅ βα sin⋅− cos αsin− YB βsin βcos 0 Body Axes Component ZB βα cos⋅sin βα cos⋅− sin αcos Angular Velocity relations αβ sinP ⋅= & ααβ cscsec ⋅=⋅−= PR& α&=Q Q=α& αβ cos⋅−= &R αtan0 ⋅+= RP Body Axis to stability Axis Angular Velocity relations αα sinRPP s ⋅+⋅= cos αα sinRPP ss ⋅−⋅= cos QQ s = s QQ = αα cos⋅+⋅−= RsinPR s αα cos⋅+⋅= ss RsinPR AERODYNAMIC SUMMARY SHEET Prepared by Vladimir SMOLKO 3 LONGITUDINAL Static trim H t LMDLMM V q q CC c Z C c X CCC tNACWBcaCG ⋅⋅−+⋅+⋅+= .. For symmetrical Airfoil ( )εααα −+−⋅= it tiWtL aC Static Stability −⋅⋅⋅−+⋅+⋅= α ε αα ααα d d V q q C d dC c Z d dC c X CC H t L MD LM H NAC 1 Elevator/g Turn n A PullUpForA SW gAcC dC dC Cq SW dn d PMCG PMN m L m MZ e q e += = ⋅ +⋅ ⋅ = − − 2 .. .. 1 1 1 4 0 444 3444 21 43421 ρδ δ Neutral Point (N0) AirplaneL M CG dC dC XN −=0 ( )0NXCC CGLM −⋅= αα cS lS V d d V q q a a dC dC NN HHHH t w t L M Nac BODYWING ⋅ ⋅ = −⋅⋅ ⋅+−= α ε 100 Manoeuvre Point (M.P.) 4444 84444 7644 844 76 Turn M UpPull M nW qcSC N W qcSC NN qq +⋅ ⋅ −= ⋅ −= 2000 1 1 44 ρρ Short Period Approximation Natural Freq.,Damping sp sp n q q n M U Z M SecRadM U MZ ω ςω α α α α ⋅ ++− =−= 2 ;/ 0 0 & Phugoid Approximation p p n UU n X SecRad U gZ ω ςω ⋅ − = − = 2 ;/ 0 Hinge Moments αδδ αδδ ⋅+⋅+⋅+= ⋅⋅ = HcHTABHHH cc H CCCCC cSq HM C cTAB0 Oscillatory Motion d d P π ω 2 = n ωζσ ⋅= 2 1 ζωω −⋅= nd 12 2 1 TT X X Ln − =σ n Amp T ωζ ⋅ = 693.0 2 1 Feedback Control system Transfer Function Block Diagram Closed Loop ⋅+ = )()(1 )( )( )( sHsG sG sX sY Open loop )()( sHsG Root Locus Analysis )( )( 1 )( )( )( sD sN K sG sX sY + = )()()( )()()( )( )( 21 21 n m PsPsPs ZsZsZs K sD sN K +⋅⋅⋅+⋅+ +⋅⋅⋅+⋅+ = s ~ Laplace operator (o) Zeros~Roots of Nominator Z1, Z2,···Zm (x) Poles~Roots of Denominator P1, P2,···Pn Table of Laplace Transforms Time Function Laplace Transform Unit Impulse δ(t) 1 Unit Step u(t) s 1 Unit Ramp t 2 1 s Polinomial tn 1 ! +ns n Exponential e-at as + 1 Sine Wave sin(ωt) 22 ω ω +s Cosine Wave cos(ωt) 22 ω+s s Damping Sine Wave e-atsin(ωt) 22)( ω ω ++ as Damping Cosine Wave e-atcos(ωt) 22)( ω++ + as as Stability Derivative Effect Stability Derivative Quantity Most Affected How affected Cmq Damping of the short period Increase Cmq to increase the damping Cmα Natural frequency of the short period Increase Cmα to increase the frequency CXu Damping of the phugoid Increase CXu to increase the damping Longitudinal Czu Natural frequency of phugoid Increase to increase the frequency Cnr Damping of the Dutch Roll Increase Cnr to increase the damping Cnβ Natural Frequency of the Dutch Roll Increase Cnβ to increase the natural frequency Clp Roll subsidence Increase Clp to increase 1/TR Lateral Directional Clβ Spiral divergence Increase Clβ for spiral stability LATERAL-DIRECTIONAL Static trim 0 ' =+++ qSbLCCC TRlAll RA δδβ δδβ 0=+++ qSbNCCC TRnAnn RA δδβ δδβ 0cos =⋅⋅+++ γφδδβ δδβ sinCCCC LRYAYY RA Static Stability bS lS V d d V q q aC VVVV t Vn ⋅ ⋅ = −⋅⋅ ⋅−= β σ β 1 Roll Performance ( )1)( 2 −⋅ ⋅ +⋅ ⋅ −= tL P A P A PAA e L L t L L t δδ φ δδ P A ss T t ss L L PePtP AR δδ ⋅ −= −⋅= − 1)( RadAngleHelix C C V bP A l l P A δδ ⋅= ⋅ ⋅ 2 Roll Time Constant 1 2 2 0 sec 2 4 1 − −⋅ ⋅ ⋅ ⋅+⋅−= pP nL ZZ n l l XXR CC bm I C C C I bSU T β βρ Spiral Time Constant 1 0 sec 1 − −⋅ ⋅ −= rr P ln n l lS CC C C CU g T β β Dutch Roll Approximation ( ) SecRadYNUNNY U rrn / 1 0 0 βββω −+= ⋅−⋅ ⋅−+−= pr n ZZ L n l XX ZZ n ZZ Y n d C I mb C C C I I C I mb C m SU 224 22 0 β β βω ρ ς 22 1 1 Rd XXn ZZl d T IC IC ω β φ β β + −= AERODYNAMIC SUMMARY SHEET Prepared by Vladimir SMOLKO 4 Jet Airplane Performance Ground ( )[ ]φµµ sinWqSCCWT W g a LDTx ⋅−⋅−−−⋅= For average Values TT, W, CD, CL, µ, ф (Runway Gradient) At 0.707 VT.O. )( 0444.0 tan 2 .. 2 Feet BVA BVA Ln B W ceDis OT W − − ⋅ ⋅ = )( 1 11 1026.0 .. .. Sec VAB VAB VAB VAB Ln BA W Time W W OT OT ⋅+ ⋅− ⋅− ⋅+ ⋅ ⋅ ⋅ = ( ) ( )KtsVKTASV WOT →→.. ( )φµ sinWWTA T ⋅−−= ( ) LD CCSB µσ −⋅⋅⋅= 00339.0 In Flight AxisXAccelLongu S →& AxisZAccelVertw S →& Wing level ф=0 ( )γsinWDaT W g u ⋅−−⋅⋅= cos& ( )αγ sinTWL W g w ⋅−⋅−⋅= cos& ⋅ −−= g V g w nZ θ&& 1 Energy Equation T.E. =P.E.+K.E.=W·h+1/2mVT 2 Specific Energy ( ) W VDT dt dV g V dt dh dt dE g V hE hh ⋅− =⋅+=+= 2 2 T.E. – Total Energy, P.E. – Potential Energy, K.E. – Kinetic Energy Navigation Two points A and B )( WestDegLatitudeLat +→ )( NothernDegLongitudeLong +→ Straight Line Navigation (Rhumb line Navigation)- Loxodromia [ ] ( ) ( )( ) ( )( )[ ] ⋅+−⋅+⋅ −⋅ = − A 0 B 00 BA1 NorthDeg Lat5.045tanLnLat5.045tanLn180 LongLong tan π Ψ [ ] ( ) 44444 844444 76 0cosif AB AB .M.N )Latcos(LongLong60 cos LatLat 60S = ⋅−⋅= − ⋅= Ψ Ψ Great Circle Navigation - Orthdomia [ ] [ ])LongLongcos()Latcos()Latcos()Lat(sin)Lat(sincos60 ABBABA 1 .M.N S −⋅⋅+⋅⋅= − Jet Airplane Performance Climb__ Descent min/Ft dH dV g V 1 )Kts(V W DT 28.101CR T ⋅+ ⋅ − ⋅= ⋅ dH dV g V For constant VC Ve M Above 36089 --- 0.7�M2 0 Below 36089 -0.014055�M+0.65667�M2-0.214204�M3 0.567�M2 -0.133�M2 Range ⋅= ⋅ ⋅ ⋅⋅ = 2 1 2 10 .)M.N( W W LnW W W Ln D L TSFC Ma R θ Lb NAM W Range Factor Endurance = ⋅ ⋅= 2 1 2 1 )Hours( W W Ln V W W W Ln D L TSFC 1 T a0–Speed Sound knots at Sea level Lb NAM Nautical Air Miles Per Lb Fuel Parabolic Drag Polar ( )21 D 21 L .)M.N( MAX WW C C STSFC 40.34 R RANGE MAX − ⋅ ⋅⋅ = σ eA C CC 2 L DD 0 π += 3 eAC C 0 RANGE MAX D L π = 0 RANGE MAX RANGE MAX D L D 21 L C4 C 3 C C = ⋅ ⋅= 2 1 D L )Hours( MAX W W Ln C C TSFC 1 T RANGE MAX 0 ENDURANCE MAX DL AeCC π= Range Correction Factor +⋅ + = + TSFC TSFC 1 C C 1 1 R R 1 D D ∆∆ ∆ Manoeuvres Steady State Pull Up 22 PP XRRZ −−= ( ))cosn(29.11VR 2 )Kts()Ft( P γ−⋅= V )cosn(g Q )Sec/Rad( γ γ −⋅ == & Steady State Turn φcos 1n = ⇒ ⋅ = Sec Rad V tang φ Ψ& ( )φtang5.2132VR 2 )Kts()Ft( T ⋅⋅= φΨ sinQ ⋅= & φΨ cosR ⋅= & Stability Axis −⋅= n 1 n V g Q )Sec/Rad( 1n Vn g R 2 )Sec/Rad( −⋅ ⋅ = )utes(mintanV0055.0360TurnToTime Kts 0 φψ ⋅= TRAJECTORY +⋅−= W SqC sing dt dV Dγ V cosg dt d γγ ⋅− = γcosVV TTx = γsinVV TTz = Drag Coefficient Data One side Flat Plate Laminar Flow n f R 328.1 C = Turbulent Flow ( ) 58.2n10 f Rlog 455.0 C = CD Rn 10 4 To 106 Based on Frontal Area Wetted Area Direction Of Flow � � � ⊳600 | Rn=9�10 6 t/c=12% 2-Dim 1.17 1.20 2.30 2.05 1.55 1.55 1.98 0.0058 3-Dim .47 0.38 1.42 1.05 0.80 0.50 1.17 0.0030 JET ENGINE PERFORMANCE Gross Thrust P&W Engine Station (J-57 and TF-33) ( )0999aG PPAV g W F −⋅−⋅= ( ) ( )09909an PPAVV g W F −⋅−−⋅= 444444 3444444 21 4444444 34444444 21 444 3444 21 44 344 21 DragRam am t t t t ta t ta tr ThrustGross imaryPr c h cgp0 Fan fff0 am n P P P PW W F A A ACPACP F 1 1 2 2 2 2 2 2 ⋅ ⋅ ⋅ − ⋅⋅⋅⋅+⋅⋅⋅= δ θ δ θ δ ΨΨ δ − ⋅ − = − 1 P P 1 2 1 am t unchoked γ γ γ γ Ψ 1 1 2 P P 2 1 1 am t choked − + ⋅⋅= −γ γ Ψ fC Fan Gross Thrust Coefficient )PP(f amT3 gC Primary Gross Thrust Coefficient )PP(f amT7 cf A,A Exhaust Exit Area Fan, Primary ch AA Ratio A9 hot to cold )PT(f amT7 2 2 t taW δ θ is Corrected engine airflow Lbs/sec ) N ,PP(f 2 2 t amT θ 2 2 2 t ta tr W F δ θ δ is Ram Drag Parameter Lbs/(Lbs/Sec) 2 0 M 2 1 1 M g a − + ⋅ γ 1 2 t t P P is inlet pressure recovery ratio, dimensionless M, W f 2 2 t ta δ θ am t P P 1 is ram pressure ratio, dimensionless 1 2 M 2 1 1 − − + γ γ γ