[samples] Use Gaussian1 functor where applicable

Author: ischoegl

samples/python/reactors/fuel_injection.py

@@ -9,7 +9,7 @@
 a `MassFlowController`, and the use of the `SolutionArray` class to store results
 during reactor network integration and use these results to generate plots.
 
-Requires: cantera >= 2.5.0, matplotlib >= 2.0
+Requires: cantera >= 3.1, matplotlib >= 2.0
 
 .. tags:: Python, combustion, reactor network, kinetics, pollutant formation, plotting
 """
@@ -33,17 +33,15 @@
 r = ct.IdealGasReactor(gas)
 r.volume = 0.001  # 1 liter
 
+def fuel_mdot(total_mass=3.0e-3, std_dev=0.5, center_time=2.0):
+    """Create a Gaussian pulse function."""
+    # units are kg for mass and seconds for times
+    amplitude = total_mass / (std_dev * np.sqrt(2 * np.pi))
+    fwhm = std_dev * 2 * np.sqrt(2 * np.log(2))
+    return ct.Func1("Gaussian", [amplitude, center_time, fwhm])
 
-def fuel_mdot(t):
-    """Create an inlet for the fuel, supplied as a Gaussian pulse"""
-    total = 3.0e-3  # mass of fuel [kg]
-    width = 0.5  # width of the pulse [s]
-    t0 = 2.0  # time of fuel pulse peak [s]
-    amplitude = total / (width * np.sqrt(2*np.pi))
-    return amplitude * np.exp(-(t-t0)**2 / (2*width**2))
-
-
-mfc = ct.MassFlowController(inlet, r, mdot=fuel_mdot)
+# Create an inlet for the fuel, supplied as a Gaussian pulse
+mfc = ct.MassFlowController(inlet, r, mdot=fuel_mdot())
 
 # Create the reactor network
 sim = ct.ReactorNet([r])

samples/python/reactors/nanosecond_pulse_discharge.py

@@ -34,9 +34,8 @@
 EN_peak = 190 * 1e-21  # 190 Td
 pulse_center = 24e-9  # 24 ns
 pulse_width = 3e-9  # standard deviation (3 ns)
-
-def gaussian_EN(t):
-    return EN_peak * np.exp(-((t - pulse_center)**2) / (2 * pulse_width**2))
+pulse_fwhm = pulse_width * 2 * (2 * np.log(2))**.5
+gaussian_EN = ct.Func1("Gaussian", [EN_peak, pulse_center, pulse_fwhm])
 
 # setup
 gas = ct.Solution('example_data/methane-plasma-pavan-2023.yaml')
@@ -55,7 +54,7 @@ def gaussian_EN(t):
 dt_chunk = 1e-9  # 1 ns chunk
 states = ct.SolutionArray(gas, extra=['t'])
 
-print('{:>10} {:>10} {:>10} {:>14}'.format('t [s]', 'T [K]', 'P [Pa]', 'h [J/kg]'))
+print(f"{'t [s]':>10} {'T [K]':>10} {'P [Pa]':>10} {'h [J/kg]':>14}")
 
 # simulate in 1 ns chunks
 t = 0.0
@@ -66,8 +65,7 @@ def gaussian_EN(t):
     while sim.time < t_end:
         sim.advance(sim.time + dt_max) #use sim.step
         states.append(r.thermo.state, t=sim.time)
-        print('{:10.3e} {:10.3f} {:10.3f} {:14.6f}'.format(
-            sim.time, r.T, r.thermo.P, r.thermo.h))
+        print(f"{sim.time:10.3e} {r.T:10.3f} {r.thermo.P:10.3f} {r.thermo.h:14.6f}")
 
     EN_t = gaussian_EN(t)
     gas.reduced_electric_field = EN_t

test/python/test_reactor.py

@@ -2474,15 +2474,15 @@ def setup_combustor_tests(self):
         fuel_mdot = factor * fuel_mw
 
         # The igniter will use a time-dependent igniter mass flow rate.
-        def igniter_mdot(t, t0=0.1, fwhm=0.05, amplitude=0.1):
-            return amplitude * math.exp(-(t - t0) ** 2 * 4 * math.log(2) / fwhm ** 2)
+        def igniter_mdot(amplitude=0.1, t0=0.1, fwhm=0.05):
+            return ct.Func1("Gaussian", [amplitude, t0, fwhm])
 
         # create and install the mass flow controllers. Controllers m1 and m2 provide
-        # constant mass flow rates, and m3 provides a short Gaussian pulse only to ignite
-        # the mixture
+        # constant mass flow rates, and m3 provides a short Gaussian pulse only to
+        # ignite the mixture
         m1 = ct.MassFlowController(fuel_in, combustor, mdot=fuel_mdot)
         m2 = ct.MassFlowController(oxidizer_in, combustor, mdot=oxidizer_mdot)
-        m3 = ct.MassFlowController(igniter, combustor, mdot=igniter_mdot)
+        m3 = ct.MassFlowController(igniter, combustor, mdot=igniter_mdot())
 
         # put a valve on the exhaust line to regulate the pressure
         valve = ct.Valve(combustor, exhaust, K=1.0)