f0 34.5[Hz] "Frequency for optimization"
W 18[m] "Room width"
H 9[m] "Room height"
dH 1[m] "Design domain height"
Rob 1[m] "Objective domain radius"
xob 16[m] "Objective domain x-coordinate"
yob 2[m] "Objective domain y-coordinate"
rho1 1.204[kg/m^3] "Air density"
K1 141.921e3[Pa] "Air bulk modulus"
rho2 2643.0[kg/m^3] "Aluminum density"
K2 68.7e10[GPa] "Aluminum bulk modulus"
volfrac 0.85 "Design domain volume fraction"
alpha_K 0.001 "Damping coefficient"
hmax 0.3 "Maximum element size"
rmin 0.1*hmax "Minimum element size"
beta 32 "Projection slope"