IBM gives different results with MPI #875
Description
IBM simulations don't produce the same results when an immersed boundary lies on a processor boundary when running with multiple ranks. This case file
import json
import math
Mu = 1.84e-05
gam_a = 1.4
# Configuring case dictionary
print(
json.dumps(
{
# Logistics
"run_time_info": "T",
# Computational Domain Parameters
# For these computations, the cylinder is placed at the (0,0,0)
# domain origin.
# axial direction
"x_domain%beg": 0.0e00,
"x_domain%end": 8.0e-03,
# r direction
"y_domain%beg": 0.0e00,
"y_domain%end": 6.0e-03,
"cyl_coord": "F",
"m": 199,
"n": 149,
"p": 0,
"cfl_adap_dt": "T",
"cfl_target": 0.3,
"n_start": 0,
"t_save": 2e-5,
"t_stop": 2e-3,
# Simulation Algorithm Parameters
# Only one patches are necessary, the air tube
"num_patches": 1,
# Use the 5 equation model
"model_eqns": 2,
"alt_soundspeed": "F",
# One fluids: air
"num_fluids": 1,
# No need to ensure the volume fractions sum to unity at the end of each
# time step
"mpp_lim": "F",
# Correct errors when computing speed of sound
"mixture_err": "T",
# Use TVD RK3 for time marching
"time_stepper": 3,
# Use WENO5
"weno_order": 5,
"weno_eps": 1.0e-16,
# 'weno_Re_flux' : 'T',
"weno_avg": "T",
"avg_state": 2,
"mapped_weno": "T",
"null_weights": "F",
"mp_weno": "T",
"riemann_solver": 2,
"wave_speeds": 1,
# We use ghost-cell
"bc_x%beg": -3,
"bc_x%end": -3,
"bc_y%beg": -2,
"bc_y%end": -2,
# Set IB to True and add 1 patch
"ib": "T",
"num_ibs": 1,
"viscous": "T",
# Formatted Database Files Structure Parameters
"format": 1,
"precision": 2,
"prim_vars_wrt": "T",
"E_wrt": "T",
"parallel_io": "T",
"c_wrt": "T",
# Patch: Constant Tube filled with air
# Specify the cylindrical air tube grid geometry
"patch_icpp(1)%geometry": 3,
"patch_icpp(1)%x_centroid": 4.0e-03,
# Uniform medium density, centroid is at the center of the domain
"patch_icpp(1)%y_centroid": 3.0e-03,
"patch_icpp(1)%length_x": 8.0e-03,
"patch_icpp(1)%length_y": 6.0e-03,
# Specify the patch primitive variables
"patch_icpp(1)%vel(1)": 5e00,
"patch_icpp(1)%vel(2)": 0.0e00,
"patch_icpp(1)%pres": 1.0e00,
"patch_icpp(1)%alpha_rho(1)": 1.0e00,
"patch_icpp(1)%alpha(1)": 1.0e00,
# Patch: Cylinder Immersed Boundary
"patch_ib(1)%geometry": 2,
"patch_ib(1)%x_centroid": 3.9e-03,
"patch_ib(1)%y_centroid": 3.15e-03,
"patch_ib(1)%radius": 0.5e-03,
"patch_ib(1)%slip": "F",
# Fluids Physical Parameters
"fluid_pp(1)%gamma": 1.0e00 / (gam_a - 1.0e00), # 2.50(Not 1.40)
"fluid_pp(1)%pi_inf": 0,
"fluid_pp(1)%Re(1)": 250000,
}
)
)
can be used to recreate the problem with two and four ranks (comparing results to one rank).