Introduction to Aircraft Structural Analysis (Elsevier Aerospace Engineering)

592 CHAPTER 22 Wings FortheRthcellofanN-cellwingsectioninwhichGvariesfromwalltowall,Eq.(22.5)takestheform dθ dz = 1 2 AR ∮ R q d ...

22.3 Torsion 593 Fig.22.6 Wing section of Example 22.2. Hence, δ 12 ◦= ∫ 12 ◦ ds t∗ = 1650 1.07 = 1542 Similarly, δ 12 i= 250 δ ...

594 CHAPTER 22 Wings Fig.22.7 Shear stress (N/mm^2 )distribution in wing section of Example 22.2. Fig.22.8 N-cell wing section s ...

22.4 Shear 595 determinatestructure.Thesystemofsimultaneousequationsfromwhichthefinalshearflowsarefound willthenbe“wellcondition ...

596 CHAPTER 22 Wings Fig.22.10 Moment equilibrium ofRth cell. Bycomparingwiththepuretorsioncase,wededucethat dθ dz = 1 2 ARG ⎛ ⎝ ...

22.4 Shear 597 IfthemomentcenterischosentocoincidewiththepointofintersectionofthelinesofactionofSxand Sy,Eq.(22.11)becomes 0 = ∑ ...

598 CHAPTER 22 Wings where,fromExample22.1,Ixx= 809 × 106 mm^4 .Thus,fromEq.(i), qb=− 86.8× 103 809 × 106 ∑n r= 1 Bryr=−1.07× 10 ...

22.5 Shear Center 599 ForcellIII, dθ dz = 1 2 × 413000 GREF [− 68 qs,0,II+qs,0,III( 840 + 68 + 106 (v) + 840 + 202 )+45.5× 202 ...

600 CHAPTER 22 Wings 22.6 TaperedWings........................................................................................ W ...

22.6 Tapered Wings 601 shearmodulusisconstantthroughout,theverticalwebsareall1.0mmthick,whiletheremainingwalls areall0.8mmthick: ...

602 CHAPTER 22 Wings Fromcolumn⑥ ∑^6 r= 1 Py,r=764.4N Fromcolumn⑩ ∑^6 r= 1 Px,rηr=−117846Nmm Fromcolumn ∑^6 r= 1 Py,rξr=−43680Nm ...

22.7 Deflections 603 Fig.22.14 Shear flow (N/mm) distribution in tapered beam of Example 22.4. or 0 =− 690726 + 72000 qs,0,I+ 14 ...

604 CHAPTER 22 Wings Fig.22.15 Deflection of two-cell wing section. and Ixx= 4 × 650 × 1252 + 2 × 1300 × 1252 =81.3× 106 mm^4 al ...

22.8 Cutouts in Wings 605 giving =23.5mm 22.8 CutoutsinWings.................................................................... ...

606 CHAPTER 22 Wings Ifthewingstructurewerecontinuousandtheeffectsofrestrainedwarpingatthebuilt-inendignored, theshearflowsinthe ...

22.8 Cutouts in Wings 607 Midwaybetweenstations1500and3000apointofcontraflexureoccursinthefrontandrearsparsso thatatthispointthe ...

608 CHAPTER 22 Wings Theresultantoftheshearflowsq 2 andq 3 mustbeequivalenttotheappliedtorque.Hence,formoments aboutthecenterofs ...

22.8 Cutouts in Wings 609 Fig.22.20 Shear flows (N/mm) on wing rib at station 3000 in the wing of Example 22.6. Fig.22.21 Wing b ...

610 CHAPTER 22 Wings Fig.22.22 Shear flow (N/mm) distribution at any station in the wing box of Example 22.7 without cutout. Fig ...

22.8 Cutouts in Wings 611 SolvingEqs.(i)and(ii)gives q′ 32 =117.6N/mm q′ 14 =53.1N/mm The final shear flows in bay②are found by ...