Numerical optimization design of advanced transonic wing configurations

A computationally efficient and versatile technique for use in the-design of advanced transonic wing configurations has been developed.A reliable and fast transonic wing flow-field analysis program, TWING, has been coupled with a modified quasi-Newton method, unconstrained optimization algorithm, QNMDIF, to create a new design tool.Fully three-dimensional wing designs utilizing both specified wing pressure distributions and drag-to-lift ratio minimization as design objectives are demonstrated.Because of the ix 15.TWING/QNM drag-to-lift ratio minimization result, Gates Learjet Century III wing: 48.5% span station...... 63 16.TWING/QNM drag-to-1ift ratio minimization result, Gates Learjet Century III wing: 72.7% span station...... 64 17.TWING/QNM drag-to-lift ratio minimization result, Gates Learjet Century III wing: 90.9% span station...... 65 18.Objective function (CD/C L x 100) versus the number of TWING flow solutions: Learjet wing................... 67 19.TWING/QNM pressure-design mode result, Gates Learjet Century III wing p1anform: root span station............ 69 20.TWING/QNM pressure-design mode result.Gates Learjet Century III wing planform: 48.5% span station........... 70 21.TWING/QNM pressure-design mode result, Gates Learjet ~entury III wing planform: 90.9% span station........... 71 22. Two views of the Cessna Citation III Model 650 wing geometry with aspect ratio 9.0 and leading-edge sweep of 27.2°.(a) Planform view; (b) isometric view......... 72 23.Location of the fixed (+) and movable (*) splinesupport points on the three Cessna airfoils.(a) Root station; (b) break station; (c) tip station.............. 74 24.TWING/QNM drag-to-lift ratio minimization result, Cessna Model 650 wing design: root span station......... 75 25.TWING/QNM drag-to-lift ratio minimization result.Cessna Model 650 wing design: 24.2% span station........ 76 26.TWING/QNM drag-to-lift ratio minimization result.Cessna Model 650 wing design: 48.5% span station........ 77 27.TWING/QNM drag-to-lift ratio minimization result, Cessna Model 650 wing design: 72.7% span station........ 78 28.TWING/QNM drag-to-lift ratio minimization result, Cessna Model 650 wing design: 90.9% span station........ 79 29.Objective function (CDiCL x 100) versus the number of TWING flow solutions: Cessna 650 wing................