[whydi]

Hey,


i am trying to simulate a bubble column via multiphase eulerian-eulerian method in combination with inhomogeneous discrete population balance modeling.

I am using 3 secondary air phases and a primary water phase.

Particle size range: (0.0015 -0.0095 m). 3 bins for every sec. phase.


For the initial BC i wanna check three dfferent superficial velocities: 2.5 mm/s, 12 mm/s and 22 mm/s. I am calculation PSD extern with log. normal distribution to split the inlet velocity to the three phases (its recommendes to use inlet vof = 0.5 for inlet BC).


For vel_1 = 2.5 mm/s the simulation is running as expected.
For higher PSD and sup. velocities i get floating point exception:


turbulent viscosity limited to viscosity ratio of 1.000000e+05 in 4500 cells
122 1.4323e+26 1.0931e+01 5.2766e-03 4.2743e-02 6.5920e-03 4.5624e+01 3.3434e-01 5.2486e-01 7.6019e-01 2.0885e-01 2.1696e-01 4.0172e-02 1.2179e-01 7.4441e-01 1.6435e+05 5.8688e-05 1.9009e-05 7.4979e-02 2.4100e-03 5.9303e-05 7.9606e-02 4.7052e-03 4.6173e-04 7.9623e-02 2.8203e-01 1.5422e-01 5.4670e-05 0:00:04 18
Stabilizing vof-1 to enhance linear solver robustness.
Stabilizing vof-2 to enhance linear solver robustness.
Stabilizing vof-3 to enhance linear solver robustness.


turbulent viscosity limited to viscosity ratio of 1.000000e+05 in 4500 cells


iter continuity u-water u-air u-air2 u-air3 v-water v-air v-air2 v-air3 w-water w-air w-air2 w-air3 k-water eps-water bf-0-air bf-0-air2 bf-0-air3 bf-1-air bf-1-air2 bf-1-air3 bf-2-air bf-2-air2 bf-2-air3 vf-air vf-air2 vf-air3 time/iter
123 1.4392e+29 7.7951e+00 1.0062e+00 1.8510e-01 2.5541e-01 1.5516e+01 5.4141e+00 1.4575e-01 1.0989e-01 2.6501e-01 8.7214e-01 1.4717e-01 3.6959e-01 7.0000e-01 3.1568e+07 4.9373e-05 6.3359e-05 2.3793e-03 2.0245e-03 1.1999e-04 1.8620e-03 3.9379e-03 6.6472e-04 1.8626e-03 3.2295e-01 1.1713e-01 1.7408e-02 0:00:03 17
Stabilizing vof-3 to enhance linear solver robustness.


turbulent viscosity limited to viscosity ratio of 1.000000e+05 in 4500 cells
124 5.4629e+33 1.1591e+01 6.5738e+00 7.5122e+01 2.4389e-01 1.6208e+01 1.0805e-01 2.0149e-01 4.6927e-01 9.2227e-01 1.7691e-02 1.4376e-01 9.6568e-01 7.0153e-01 3.9590e+10 8.5381e-05 2.2232e-04 1.8513e-03 3.4937e-03 2.6036e-04 1.7182e-03 6.7803e-03 6.1951e-04 1.7177e-03 7.9949e-01 6.8334e-01 4.0753e-01 0:00:03 16
Stabilizing mp-x-momentum to enhance linear solver robustness.
Stabilizing mp-y-momentum to enhance linear solver robustness.
Stabilizing mp-z-momentum to enhance linear solver robustness.
Stabilizing k to enhance linear solver robustness.
Stabilizing vof-1 to enhance linear solver robustness.
Stabilizing vof-2 to enhance linear solver robustness.
Stabilizing vof-3 to enhance linear solver robustness.


turbulent viscosity limited to viscosity ratio of 1.000000e+05 in 4500 cells
125 6.2593e+42 2.0201e+02 7.2521e+03 4.8546e+01 3.0622e-02 9.6404e-03 2.2526e-10 5.1150e-04 4.0377e-02 5.7064e-03 3.7114e-10 7.4107e-04 2.4628e-02 1.7421e+10 9.7762e+19 0.0000e+00 1.5961e-05 5.2211e-04 0.0000e+00 7.6861e-05 4.1404e-04 0.0000e+00 6.8129e-04 4.1398e-04 9.9960e-01 2.8941e-01 7.5497e-01 0:00:05 15
Stabilizing k to enhance linear solver robustness.
Stabilizing k using GMRES to enhance linear solver robustness.


Divergence detected in AMG solver: k Stabilizing vof-1 to enhance linear solver robustness.
Stabilizing vof-2 to enhance linear solver robustness.
Stabilizing vof-3 to enhance linear solver robustness.


turbulent viscosity limited to viscosity ratio of 1.000000e+05 in 2743 cells


Error at host: floating point exception


Error at Node 0: floating point exception


Error: floating point exception
Error Object: #f


I am not sure how to nterpret these error nodes. Only difference in simulations are the inlet BC.

Does somebody knows how to debug or how to interpret this error?