“…Limit cycle oscillation (LCO) is frequently encountered in engineering applications, such as, aeroelastics (Thomas et al, 2002;Huang et al, 2018;He et al, 2019a;Li and Ekici, 2019;Jonsson et al, 2019;Riso et al, 2020), bipedal robotics (Grizzle et al, 2001;Shiriaev et al, 2008;Manchester et al, 2011), and combustion (Waugh et al, 2014;Xu et al, 2020). In the context of design optimization, the scalability of computational cost with respect to the number of design variables is essential for problems with a large number of design variables and with a PDE governing equation.…”