def run_reacting_surface(self, xch4, tsurf, mdot, width):
# Simplified version of the example 'catalytic_combustion.py'
gas = ct.Solution('ptcombust-simple.cti', 'gas')
surf_phase = ct.Interface('ptcombust-simple.cti', 'Pt_surf', [gas])
tinlet = 300.0 # inlet temperature
comp = {'CH4': xch4, 'O2': 0.21, 'N2': 0.79}
gas.TPX = tinlet, ct.one_atm, comp
surf_phase.TP = tsurf, ct.one_atm
# integrate the coverage equations holding the gas composition fixed
# to generate a good starting estimate for the coverages.
surf_phase.advance_coverages(1.)
sim = ct.ImpingingJet(gas=gas, width=width, surface=surf_phase)
sim.set_refine_criteria(10.0, 0.3, 0.4, 0.0)
sim.inlet.mdot = mdot
sim.inlet.T = tinlet
sim.inlet.X = comp
sim.surface.T = tsurf
sim.solve(loglevel=0, auto=True)
self.assertTrue(all(np.diff(sim.T) > 0))
self.assertTrue(all(np.diff(sim.Y[gas.species_index('CH4')]) < 0))
self.assertTrue(all(np.diff(sim.Y[gas.species_index('CO2')]) > 0))
def test_save_restore(self):
comp = {'CH4': 0.095, 'O2': 0.21, 'N2': 0.79}
self.sim = self.create_reacting_surface(comp, tsurf=900, tinlet=300, width=0.1)
self.sim.inlet.mdot = 0.06
self.sim.inlet.T = 300
self.sim.inlet.X = comp
self.sim.surface.T = 900
self.sim.solve(loglevel=0, auto=False)
filename = self.test_work_path / "impingingjet1.yaml"
self.sim.save(filename)
self.surf_phase.TPX = 300, ct.one_atm, "PT(S):1"
sim2 = ct.ImpingingJet(gas=self.gas, width=0.12, surface=self.surf_phase)
sim2.restore(filename)
self.assertArrayNear(self.sim.grid, sim2.grid)
self.assertArrayNear(self.sim.Y, sim2.Y)
for i in range(self.sim.surface.n_components):
self.assertNear(
self.sim.value("surface", i, 0),
sim2.value("surface", i, 0)
)
def create_reacting_surface(self, comp, tsurf, tinlet, width):
gas = ct.Solution('ptcombust-simple.cti', 'gas')
surf_phase = ct.Interface('ptcombust-simple.cti', 'Pt_surf', [gas])
gas.TPX = tinlet, ct.one_atm, comp
surf_phase.TP = tsurf, ct.one_atm
# integrate the coverage equations holding the gas composition fixed
# to generate a good starting estimate for the coverages.
surf_phase.advance_coverages(1.)
return ct.ImpingingJet(gas=gas, width=width, surface=surf_phase)
def create_reacting_surface(self, comp, tsurf, tinlet, width):
self.gas = ct.Solution("ptcombust-simple.yaml", "gas")
self.surf_phase = ct.Interface("ptcombust-simple.yaml", "Pt_surf", [self.gas])
self.gas.TPX = tinlet, ct.one_atm, comp
self.surf_phase.TP = tsurf, ct.one_atm
# integrate the coverage equations holding the gas composition fixed
# to generate a good starting estimate for the coverages.
self.surf_phase.advance_coverages(1.)
return ct.ImpingingJet(gas=self.gas, width=width, surface=self.surf_phase)
# Grid refinement parameters
ratio = 3
slope = 0.1
curve = 0.2
prune = 0.06
# Set up the problem
gas = ct.Solution(rxnmech)
# set state to that of the unburned gas at the burner
gas.TPX = tburner, p, comp
# Create the stagnation flow object with a non-reactive surface. (To make the
# surface reactive, supply a surface reaction mechanism. See example
# catalytic_combustion.py for how to do this.)
sim = ct.ImpingingJet(gas=gas, width=width)
# set the mass flow rate at the inlet
sim.inlet.mdot = mdot[0]
# set the surface state
sim.surface.T = tsurf
sim.set_grid_min(1e-4)
sim.set_refine_criteria(ratio=ratio, slope=slope, curve=curve, prune=prune)
sim.set_initial_guess(
products='equil') # assume adiabatic equilibrium products
sim.show_solution()
sim.solve(loglevel, auto=True)
#
# This phase definition also references the phase 'gas' in the same input file,
# which will be created and used to evaluate all thermodynamic, kinetic, and
# transport properties. It is a stripped-down version of GRI-Mech 3.0.
surf_phase = ct.Interface("ptcombust.yaml", "Pt_surf")
surf_phase.TP = tsurf, p
gas = surf_phase.adjacent["gas"]
gas.TPX = tinlet, p, comp1
# integrate the coverage equations in time for 1 s, holding the gas
# composition fixed to generate a good starting estimate for the coverages.
surf_phase.advance_coverages(1.0)
# create the object that simulates the stagnation flow, and specify an initial
# grid
sim = ct.ImpingingJet(gas=gas, width=width, surface=surf_phase)
# Objects of class ImpingingJet have members that represent the gas inlet
# ('inlet') and the surface ('surface'). Set some parameters of these objects.
sim.inlet.mdot = mdot
sim.inlet.T = tinlet
sim.inlet.X = comp1
sim.surface.T = tsurf
# Show the initial solution estimate
sim.show_solution()
# Solving problems with stiff chemistry coupled to flow can require a
# sequential approach where solutions are first obtained for simpler problems
# and used as the initial guess for more difficult problems.
# Grid refinement parameters
ratio = 3
slope = 0.1
curve = 0.2
prune = 0.06
# Set up the problem
gas = ct.Solution(rxnmech)
# set state to that of the unburned gas at the burner
gas.TPX = tburner, p, comp
# Create the stagnation flow object with a non-reactive surface. (To make the
# surface reactive, supply a surface reaction mechanism. See example
# catalytic_combustion.py for how to do this.)
sim = ct.ImpingingJet(gas=gas, grid=initial_grid)
# set the mass flow rate at the inlet
sim.inlet.mdot = mdot[0]
# set the surface state
sim.surface.T = tsurf
sim.flame.set_steady_tolerances(default=tol_ss)
sim.flame.set_transient_tolerances(default=tol_ts)
sim.set_grid_min(1e-4)
sim.energy_enabled = False
sim.set_initial_guess(
products='equil') # assume adiabatic equilibrium products
sim.show_solution()
#
# This object will be used to evaluate all surface chemical production rates.
# It will be created from the interface definition 'Pt_surf' in input file
# 'ptcombust.cti,' which implements the reaction mechanism of Deutschmann et
# al., 1995 for catalytic combustion on platinum.
#
surf_phase = ct.Interface('ptcombust.cti', 'Pt_surf', [gas])
surf_phase.TP = tsurf, p
# integrate the coverage equations in time for 1 s, holding the gas
# composition fixed to generate a good starting estimate for the coverages.
surf_phase.advance_coverages(1.0)
# create the object that simulates the stagnation flow, and specify an initial
# grid
sim = ct.ImpingingJet(gas=gas, grid=initial_grid, surface=surf_phase)
# Objects of class StagnationFlow have members that represent the gas inlet
# ('inlet') and the surface ('surface'). Set some parameters of these objects.
sim.inlet.mdot = mdot
sim.inlet.T = tinlet
sim.inlet.X = comp1
sim.surface.T = tsurf
# Set error tolerances
sim.flame.set_steady_tolerances(default=tol_ss)
sim.flame.set_transient_tolerances(default=tol_ts)
# Show the initial solution estimate
sim.show_solution()
