Optimizing a compressor rotor

This white paper introduces an innovative technique for turbomachinery optimization, overcoming limitations of traditional adjoint methods that often require reverse engineering the computer-aided design (CAD) model or specialized CAD tool with an adjoint capability. The proposed technique couples a computation fluid dynamic (CFD) flow adjoint from CFD code with any design software without requiring adjoint capability. This is done by computing an intermediate geometric sensitivity via finite differences. This flexible approach enables direct, gradient-based optimization on complex CAD models. Demonstrating its utility, we optimized the first stage of the NASA Energy Efficient Engine (E3) turbofan engine’s high-pressure compressor, achieving nearly a 2 percent efficiency improvement with only 11 design evaluations.