Hello,
I’ve recently started using PyFR and wanted to move beyond the tutorials to something a bit more challenging. I chose the well-known T106C test case, using the baseline mesh from the HiOCFD5 workshop (21k hex elements).
I’ve read on this forum that the T106C requires a rather careful flow initialization. I’ve tried several approaches, but so far none have been stable:
-
p-progression (p0 → p1 → …): blows up
-
p-progression with entropy filter: still blows up
-
p-controller: too intrusive
-
starting directly at p=1: blows up as well
Interestingly, the solution looks reasonably physical and transient before the solver diverges.
Below I’ve included my .ini file. Any advice or suggestions would be greatly appreciated!
Andrea
[backend]
precision = single
[constants]
gamma = 1.4
mu = 0.000008
Pr = 0.71
[solver]
system = navier-stokes
order = 1
;anti-alias = flux
viscosity-correction = none
shock-capturing = none
[solver-time-integrator]
formulation = std
scheme = rk45
controller = none
atol = 1e-5
rtol= 1e-5
tstart = 0
tend = 200.00
dt = 0.00005
[soln-plugin-dtstats]
flushsteps = 100
file = dtstats.csv
header = true
[solver-interfaces]
riemann-solver = rusanov
ldg-beta = 0.5
ldg-tau = 0.1
[solver-interfaces-quad]
flux-pts = gauss-legendre
[solver-elements-hex]
soln-pts = gauss-legendre
[soln-plugin-nancheck]
nsteps = 1
[soln-plugin-writer]
dt-out = 1
basedir = ./output
basename = t106c-{t:.2f}
[solver-entropy-filter]
d-min = 1e-6
p-min = 1e-6
e-tol = 1e-6
niters = 2
formulation = nonlinear
[soln-bcs-inlet]
type = sub-in-ftpttang
pt = 1
cpTt = 3.5
theta = 32.7
phi = 90
;[soln-bcs-inlet]
;type = sub-in-frv
;rho = 0.816
;u = 0.6214730
;v = 0.3989786
;w = 0.0
[soln-bcs-outlet]
type = sub-out-fp
p = 0.753
[soln-bcs-wall]
type = no-slp-adia-wall
[soln-ics]
rho = 0.8
u = 0.0
v = 0.0
w = 0.0
p = 0.753
[soln-plugin-fluidforce-wall]
nsteps = 10
file = blade-forces.csv
header = true
quad-deg = 6
morigin = (0.0, 0.0, 0.5)