mfc3 = MassFlowController(upstream = igniter, downstream = mixer,
mdot = 0.05)
# connect the mixer to the downstream reservoir with a valve.
outlet = Valve(upstream = mixer, downstream = downstream, Kv = 1.0)
sim = ReactorNet([mixer])
# Since the mixer is a reactor, we need to integrate in time to reach
# steady state. A few residence times should be enough.
t = 0.0
for n in range(30):
tres = mixer.mass()/(mfc1.massFlowRate() + mfc2.massFlowRate())
t += 0.5*tres
sim.advance(t)
# if ignited, turn the igniter off.
# We also need to restart the integration in this case.
if mixer.temperature() > 1200.0:
mfc3.set(mdot = 0.0)
sim.setInitialTime(t)
print '%14.5g %14.5g %14.5g %14.5g %14.5g' % (t, mixer.temperature(),
mixer.enthalpy_mass(),
mixer.pressure(),
mixer.massFraction('CH4'))
# view the state of the gas in the mixer
print mixer.contents()
# flow rates change or if there is chemistry occurring.
mixer = Reactor(gas_b)
# create two mass flow controllers connecting the upstream reservoirs
# to the mixer, and set their mass flow rates to values corresponding
# to stoichiometric combustion.
mfc1 = MassFlowController(upstream=res_a,
downstream=mixer,
mdot=rho_a * 2.5 / 0.21)
mfc2 = MassFlowController(upstream=res_b, downstream=mixer, mdot=rho_b * 1.0)
# connect the mixer to the downstream reservoir with a valve.
outlet = Valve(upstream=mixer, downstream=downstream, Kv=1.0)
sim = ReactorNet([mixer])
# Since the mixer is a reactor, we need to integrate in time to reach
# steady state. A few residence times should be enough.
t = 0.0
for n in range(30):
tres = mixer.mass() / (mfc1.massFlowRate() + mfc2.massFlowRate())
t += 0.5 * tres
sim.advance(t)
print '%14.5g %14.5g %14.5g %14.5g %14.5g' % (
t, mixer.temperature(), mixer.enthalpy_mass(), mixer.pressure(),
mixer.massFraction('CH4'))
# view the state of the gas in the mixer
print mixer.contents()
# methods
sdot = surf.netProductionRates(surf)
cdot = surf.creationRates(surf)
ddot = surf.destructionRates(surf)
for ks in range(nsurf):
ratio = sdot[ks] / (cdot[ks] + ddot[ks])
if ratio < 0.0: ratio = -ratio
if ratio > 1.0e-9 or time < 10 * dt:
alldone = 0
if alldone: break
# set the gas object state to that of this reactor, in
# preparation for the simulation of the next reactor
# downstream, where this object will set the inlet conditions
gas = r.contents()
dist = n * rlen * 1.0e3 # distance in mm
# write the gas mole fractions and surface coverages
# vs. distance
writeCSV(f, [dist, r.temperature() - 273.15,
r.pressure() / OneAtm] + list(gas.moleFractions()) +
list(surf.coverages()))
f.close()
# make a reaction path diagram tracing carbon. This diagram will show
# the pathways by the carbon entering the bed in methane is convered
# into CO and CO2. The diagram will be specifically for the exit of
# the bed; if the pathways are desired at some interior point, then
# methods
sdot = surf.netProductionRates(surf)
cdot = surf.creationRates(surf)
ddot = surf.destructionRates(surf)
for ks in range(nsurf):
ratio = sdot[ks]/(cdot[ks] + ddot[ks])
if ratio < 0.0: ratio = -ratio
if ratio > 1.0e-9 or time < 10*dt:
alldone = 0
if alldone: break
# set the gas object state to that of this reactor, in
# preparation for the simulation of the next reactor
# downstream, where this object will set the inlet conditions
gas = r.contents()
dist = n*rlen * 1.0e3 # distance in mm
# write the gas mole fractions and surface coverages
# vs. distance
writeCSV(f, [dist, r.temperature() - 273.15,
r.pressure()/OneAtm] + list(gas.moleFractions())
+ list(surf.coverages()))
f.close()
# make a reaction path diagram tracing carbon. This diagram will show
# the pathways by the carbon entering the bed in methane is convered
# into CO and CO2. The diagram will be specifically for the exit of
# the bed; if the pathways are desired at some interior point, then
def PFR(self, volume, NReactors):
initial_gas = self.InitialGas()
gas = self._gas1
T = gas.temperature()
P = gas.pressure()
x = gas.moleFractions()
initial_gas.setState_TPX(T, P, x)
upstreams = numpy.empty(self._code - 1, dtype=object)
ms = numpy.empty(self._code - 1, dtype=object)
mass_flow = self._args[1]
TOL = 1.0E-10
Niter = 20
nsp = gas.nSpecies()
wdot = [''] * nsp
wold = [''] * nsp
volume_n = volume / NReactors
tres = 0.0
for i in range(0, NReactors):
reactor = Reactor(initial_gas, volume=volume_n, energy='on')
upstream = Reservoir(initial_gas)
downstream = Reservoir(initial_gas)
m = MassFlowController()
m.install(upstream, reactor)
m.set(mass_flow)
if (i == 0):
ControllerCount = 0
for code in range(2, self._argslength, 2):
upstreams[ControllerCount] = Reservoir(self._args[code])
ms[ControllerCount] = MassFlowController()
ms[ControllerCount].install(upstreams[ControllerCount],
reactor)
ms[ControllerCount].set(self._args[code + 1])
mass_flow += self._args[code + 1]
ControllerCount += 1
v = Valve()
v.install(reactor, downstream)
v.setValveCoeff(Kv=0.1)
sim = ReactorNet([reactor])
dt = reactor.mass() / mass_flow
tnow = 0.0
wold = initial_gas.netProductionRates()
while (tnow < Niter * dt):
tnow += dt
sim.advance(tnow)
max_change = 0.0
wdot = initial_gas.netProductionRates()
for k in range(0, nsp):
max_change = max(math.fabs(wdot[k] - wold[k]), max_change)
wold[k] = wdot[k]
if (max_change < TOL):
break
tres += reactor.mass() / mass_flow
T = reactor.temperature()
P = reactor.pressure()
reactor = Reactor(initial_gas)
x = reactor.contents().moleFractions()
initial_gas.setState_TPX(T, P, x)
f = self.FuelMassAnalyzer(initial_gas, mass_flow)
return initial_gas, mass_flow, tres, f
def PSRCalc(self, volume, tfinal):
initial_gas = self.InitialGas()
gas = self._gas1
NoGas = 0 ## Ignition isn't provided if NoGas = 0
mass_flow = 0
upstreams = numpy.empty(self._code, dtype=object)
ms = numpy.empty(self._code, dtype=object)
reactor = Reactor(initial_gas, volume=volume, energy='on')
ControllerCount = 0
for code in range(0, self._argslength, 2):
upstreams[ControllerCount] = Reservoir(self._args[code])
ms[ControllerCount] = MassFlowController()
ms[ControllerCount].install(upstreams[ControllerCount], reactor)
ms[ControllerCount].set(self._args[code + 1])
mass_flow += self._args[code + 1]
ControllerCount += 1
exhaust = Reservoir(gas)
v = Valve()
v.install(reactor, exhaust)
v.setValveCoeff(Kv=0.5) #Change made from 1.0 to 0.5
sim = ReactorNet([reactor])
tnow = 0.0
tracker = datetime.now()
LoopCounter = 0
while (tnow < tfinal):
LoopCounter += 1
tnow = sim.step(tfinal)
tres = reactor.mass() / mass_flow
currenttime = datetime.now()
d = reactor.massFractions()
IndexCounter = 0
for item in d:
if item > 1:
badguy = 1
baditem = item
break
else:
badguy = 0
IndexCounter += 1
if badguy:
break
b = (currenttime.time().minute - tracker.time().minute)
if (b > 2):
break
if (IndexCounter >= gas.nSpecies()):
badSpecie = 'No Bad Species present'
baditem = 'None'
else:
badSpecie = gas.speciesName(IndexCounter)
tres = reactor.mass() / v.massFlowRate()
T = reactor.temperature()
P = reactor.pressure()
reactor = Reactor(initial_gas)
x = reactor.contents().moleFractions()
initial_gas.setState_TPX(T, P, x)
return initial_gas, mass_flow, tres
