Some references which might be helpful:
 Kyriakos C. Giannakoglou and Dimitrios I. Papadimitriou ,"Adjoint Methods for Shape Optimization", in Optimization and Computational Fluid Dynamics. Thévenin, Dominique; Janiga, Gábor (Eds.) 2008, XVI, 294 p. 149 illus.
 O. Soto and R. Löhner, "On the Computation of Flow Sensitivities From Boundary Integrals", AIAA-04-0112 (2004).
 C. Othmer, "A continuous adjoint formulation for the computation of topological and surface sensitivities of ducted flows", Int. J. Num. Meth. Fluids, Vol. 58, pp. 861–877 (2008).
 K. Morimoto, Y. Suzuki, N. Kasagi, "Optimal Shape Design of Compact Heat Exchangers Based on Adjoint Analysis of Momentum and Heat Transfer", J. Therm. Sci. Tech., Vol. 5, No. 1, pp.24-35 (2010).