a 0.25[m] Pipe radius
L 1.5[m] Pipe length
rho_air 1.25[kg/m^3] Air density
c_air 343[m/s] Speed of sound in air
a0 1[m/s^2] Applied piston acceleration
fmin 10[Hz] Minimum study frequency
fmax 1000[Hz] Maximum study frequency
hmax c_air/fmax/6 Mesh size to resolve the minimum wavelength
alpha11 3.832 Zero of the first derivative of the Bessel function
fcut (alpha11*c_air/a)/(2*pi) Cutoff frequency