The unique thermal and mechanical properties exhibited by shape memory alloys (SMAs) present exciting design possibilities in the field of aerospace engineering. When properly trained, SMA wires act as linear actuators by contracting when heated and returning to their original shape when cooled. These SMA wire actuators can be attached to points on the inside of an airfoil, and can be activated to alter the shape of the airfoil. This shape-change can effectively increase the efficiency of a wing in flight at several different flow regimes. To determine the necessary placement of the SMA wire actuators within the wing, a global optimization method that incorporates a coupled structural, thermal, and aerodynamic analysis has been utilized. A genetic algorithm has been chosen as the optimization tool to efficiently converge to a design solution. The genetic algorithm used in this case is a hybrid version with global search and optimization capabilities augmented by the simplex method with selective line search as a local search technique. A cost function based on the aerodynamic properties of the airfoil has been used to optimize this design problem to maximize the lift-to-drag ratio for a reconfigured airfoil shape at subsonic flow conditions. A wind tunnel model reconfigurable wing was fabricated based on the design optimization to verify the predicted structural and aerodynamic response. Wind tunnel tests indicated an increase in lift for a given flow velocity and angle of attack by activating the SMA wire actuators. The pressure data taken during the wind tunnel tests followed the trends expected from the numerical pressure results.

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Measurements of the cloud point (CP) of non-ionic surfactant polyoxyethylene (20) sorbitan monooleate (Tween 80) were performed in aqueous solution and in the presence of ceftriaxone sodium trihydrate (CFT) drug, with specific attention to CFT drug + different salts mixtures studied and discussed in detail. The CP values of Tween 80 in aqueous medium tend to reduce with enhanced concentration of surfactant. The CP values of Tween 80 solutions were also found to be decreased with increasing concentrations of drug used. The CP values of Tween 80 + drug mixtures were found to be lower in magnitude in the presence of salts in comparison to their absence, and the outcomes of sodium salts (between 0.001 and 0.2 mol·kg–1) in reducing CP values were found to be in the following order: NaCl < Na2SO4 < Na2CO3. In the case of potassium salt the order of reducing the CP values of Tween 80 + drug is similar, but in the case of ammonium salt the order is NH4Cl < Na2CO3 < (NH4)2SO4. The influence of cationic co-ions such as Na+, K+, and NH4 + on decreasing the CP of Tween 80 + drug solutions is found to be in the following order: NH4Cl < KCl < NaCl, (NH4)2SO4 < K2SO4 < Na2SO4, and (NH4)2CO3 < K2CO3 < Na2CO3. The values of ΔG 0 c were achieved to be positive for the total studied solutions which indicates the nonspontaneous nature of clouding. The ΔH 0 c and ΔS 0 c values were found to be negative in almost all cases in the presence of salts except for the CFT + water system. The negative values of ΔH 0 c and ΔS 0 c decreased with increasing concentrations of salts.

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