updated code to use pymapdl to create geometry

Author: krishnatejas12

examples/00-systemcoupling/cht_pipe.py

@@ -40,11 +40,11 @@
 the heated wall of the pipe conducts heat to the inner wall, which in turns heats the fluid and
 cools down the walls of the pipe.
 
-#image
+
 
 The flow is smooth inside the pipe and the outer wall of the pipe is adiabatic. Fluid enters
-at an initial temperature of 300K while the outside pipe of the wall is at some higher
-temperature. The setup is simulated for a few iterations to allow the examination
+at an initial temperature of 300K while the outside pipe of the wall is at 400K. 
+The setup is simulated for a few iterations to allow the examination
 of the temperature field in the pipe.
 
 """
@@ -58,189 +58,185 @@
 # ~~~~~~~~~~~~~~~~~~~~~~~~
 # Import ``ansys-systemcoupling-core``, ``ansys-fluent-core``
 
+import ansys.mapdl.core as pymapdl
 import ansys.fluent.core as pyfluent
-
 import ansys.systemcoupling.core as pysyc
+from ansys.systemcoupling.core import examples
 
-# ===
-
-# launch Fluent session and read in mesh file
-pipe_fluid_session = pyfluent.launch_fluent(start_transcript=False)
-pipe_fluid_mesh_file = "pipe_fluid.msh.h5"
-pipe_fluid_session.file.read(file_type="mesh", file_name=pipe_fluid_mesh_file)
-
-# turn on energy model
-pipe_fluid_session.setup.models.energy.enabled = True
-
-# add water material
-pipe_fluid_session.setup.materials.database.copy_by_name(
-    type="fluid", name="water-liquid"
-)
-
-# set up cell zone conditions
-pipe_fluid_session.setup.cell_zone_conditions.fluid["fluid"].material = "water-liquid"
-
-# set up boundary conditions
-pipe_fluid_session.setup.boundary_conditions.velocity_inlet[
-    "inlet"
-].momentum.velocity = 0.1
-pipe_fluid_session.setup.boundary_conditions.wall["wall"].thermal.thermal_bc = (
-    "via System Coupling"
-)
-
-# set up solver settings - 1 fluent iteration per 1 coupling iteration
-pipe_fluid_session.solution.run_calculation.iter_count = 1
-
-# ===
-
-# launch another Fluent session and read in mesh file
-pipe_solid_session = pyfluent.launch_fluent(start_transcript=False)
-pipe_solid_mesh_file = "pipe_solid.msh.h5"
-pipe_solid_session.file.read(file_type="mesh", file_name=pipe_solid_mesh_file)
-
-# turn on energy model
-pipe_solid_session.setup.models.energy.enabled = True
-
-# add copper material
-pipe_solid_session.setup.materials.database.copy_by_name(type="solid", name="copper")
-
-# set up cell zone conditions
-pipe_solid_session.setup.cell_zone_conditions.solid["solid"].material = "copper"
-
-# set up boundary conditions
-pipe_solid_session.setup.boundary_conditions.wall["outer_wall"].thermal.thermal_bc = (
-    "Temperature"
-)
-pipe_solid_session.setup.boundary_conditions.wall["outer_wall"].thermal.t.value = 350
-
-pipe_solid_session.setup.boundary_conditions.wall["inner_wall"].thermal.thermal_bc = (
-    "via System Coupling"
-)
-
-pipe_solid_session.setup.boundary_conditions.wall["insulated1"].thermal.thermal_bc = (
-    "Heat Flux"
-)
-pipe_solid_session.setup.boundary_conditions.wall["insulated1"].thermal.q.value = 0
-
-pipe_solid_session.setup.boundary_conditions.wall["insulated2"].thermal.thermal_bc = (
-    "Heat Flux"
+# %%
+# Download the mesh file
+fluent_msh_file = examples.download_file(
+    "fluid_domain.msh", "pysystem-coupling/cht_pipe"
 )
-pipe_solid_session.setup.boundary_conditions.wall["insulated2"].thermal.q.value = 0
-
-# set up solver settings - 1 fluent iteration per 1 coupling iteration
-pipe_solid_session.solution.run_calculation.iter_count = 1
-
-
-rho_water = 998.2
-mu_water = 1.002e-3
-k_water = 0.6
-Pr_water = 7.0
 
-rho_al = 2700
-k_al = 237
-cp_al = 900
+mapdl=pymapdl.launch_mapdl()
+mapdl.clear()
+mapdl.prep7()
+
+#%%
+#Define material properties
+mapdl.mp("EX", 1, 69e9)
+mapdl.mp("NUXY", 1, 0.33)
+mapdl.mp("DENS", 1, 2700)
+mapdl.mp("ALPX", 1, 23.6e-6)
+mapdl.mp("KXX", 1, 237)
+mapdl.mp("C", 1 , 900)
+
+#%%
+#Set element type to SOLID279
+mapdl.et(1, 279)
+mapdl.keyopt(1, 2, 1)
+print(mapdl)
+
+#%%
+#Parameter of the pipe
+r_in=0.025
+r_out=0.035
+l=0.2
+
+#%%
+#Create hollow pipe
+mapdl.cyl4(0, 0, rad1=r_in, rad2=r_out, depth=l)  
+mapdl.esize(0.002)
+mapdl.vsweep(1)
+print(mapdl.geometry.anum)
 
+# %%
+# Biot number prediction
+def biot_number(
+        rho=1000,
+        mu=1e-3,
+        cp=4180,
+        k_f=0.6,
+        k_s=237,
+        L_c=r_out-r_in,
+        U=0.1
+):
+    Re= (rho*U*L_c)/mu
+    Pr= (mu*cp)/ k_f
+    Nu= 0.023 * Re**0.8 * Pr**0.4
+    h= Nu * k_f / L_c
+    Bi= h *L_c / k_s
+    return Bi
+Bi=biot_number()
+print("The Biot number is ", Bi)
 
-# Flow and Geometry
-
-u = 0.5  # velocity [m/s]
-L = 0.5  # pipe length [m]
-D = 0.1  # inner diameter [m] → characteristic length for fluid
-t_wall = 0.12  # wall thickness [m] → characteristic length for solid conduction
-
-
-# Functions
-
-
-def getReynoldsNumber(rho, u, D, mu):
-    return rho * u * D / mu
-
-
-def getPrandtlNumber(mu, cp, k):
-    return mu * cp / k
-
-
-def getNusseltNumber(Re, Pr, L_over_D):
-
-    if Re < 2300:
-        Nu = 3.66  # laminar, fully developed
-    elif Re < 10000:
-        Nu = 0.023 * Re**0.8 * Pr**0.4  # transitional approximation
-    else:
-        Nu = 0.023 * Re**0.8 * Pr**0.4  # fully turbulent
-    return Nu
-
-
-def getConvectionCoefficient(Nu, k_fluid, D):
-    return Nu * k_fluid / D
-
-
-def getBiotNumber(h, k_solid, t_wall):
-    return h * t_wall / k_solid
-
+# %%
+# Creating the regions from the geometry for named selections
+#Inner wall NS
+mapdl.asel('S', 'AREA', '', 5, 6)
+mapdl.nsla('S', 1)
+mapdl.cm("FSIN_1", "NODE")
+mapdl.allsel()
+
+#Outer wall NS
+mapdl.asel('S', 'AREA', '', 3, 4)
+mapdl.cm("Outer_wall", "AREA")
+mapdl.allsel()
+
+#Outlet NS
+mapdl.asel('S', 'AREA', '', 2)
+mapdl.cm("Outlet", "AREA")
+mapdl.allsel()
+
+#Inlet NS
+mapdl.asel('S', 'AREA', '', 1)
+mapdl.cm("Inlet", "AREA")
+mapdl.allsel()
+
+#%%
+#Boundary conditions
+mapdl.cmsel('S', 'Outer_wall')
+mapdl.d('Outer_wall', 'TEMP', 77)
+mapdl.allsel()
+
+mapdl.cmsel('S', 'Inlet')
+mapdl.sf('ALL', 'HFLUX', 0)
+mapdl.allsel()
+
+mapdl.cmsel('S', 'Outlet')
+mapdl.sf('ALL', 'HFLUX', 0)
+mapdl.allsel()
+
+mapdl.cmsel('S', 'FSIN_1')
+mapdl.sf('FSIN_1', 'FSIN', 1)
+mapdl.allsel()
+
+#%%
+#Setup the rest of the analysis
+mapdl.run("/SOLU")
+mapdl.antype(0)
 
-Re = getReynoldsNumber(rho_water, u, D, mu_water)
-Pr = Pr_water  # directly used
-L_over_D = L / D
+# %%
+# Set up the fluid analysis
+# ~~~~~~~~~~~~~~~~~~~~~~~~~
 
-Nu = getNusseltNumber(Re, Pr, L_over_D)
-h = getConvectionCoefficient(Nu, k_water, D)
-Bi = getBiotNumber(h, k_al, t_wall)
+# %%
+# Read the pre-created mesh file
 
+fluent=pyfluent.launch_fluent(start_transcript=False)
+fluent.file.read(file_type="mesh", file_name=fluent_msh_file)
 
-print(f"{'Parameter':<25} {'Value':<15} {'Unit'}")
-print("-" * 50)
-print(f"{'Reynolds Number (Re)':<25} {Re:<15.2f}")
-print(f"{'Prandtl Number (Pr)':<25} {Pr:<15.1f}")
-print(f"{'Nusselt Number (Nu)':<25} {Nu:<15.2f}")
-print(f"{'Convection coeff (h)':<25} {h:<15.1f} W/m²·K")
-print(f"{'Biot Number (Bi)':<25} {Bi:<15.6f}")
-print("-" * 50)
-print(f"The Biot number is {Bi:.6f}")
+#%%
+#Define the fluid solver settings
+fluent.setup.models.energy.enabled =True
 
+#%%
+#Add the material
+fluent.setup.materials.database.copy_by_name(type="fluid", name="water-liquid")
 
-if Bi < 0.1:
-    print("→ Bi < 0.1 → Lumped capacitance valid (uniform wall temperature)")
-elif Bi > 10:
-    print("→ Bi > 10 → Significant temperature gradient in wall")
-else:
-    print("→ 0.1 < Bi < 10 → Moderate internal resistance")
-# ===
+fluent.setup.cell_zone_conditions.fluid["fff_fluiddomain"].material = "water-liquid"
 
-# launch System Coupling session
-syc = pysyc.launch()
-syc.start_output()
+#%%
+#Define boundary conditions
+fluent.setup.boundary_conditions.velocity_inlet["inlet"].momentum.velocity = 0.1
+fluent.setup.boundary_conditions.velocity_inlet["inlet"].thermal.temperature = 300
+fluent.setup.boundary_conditions.wall["inner_wall"].thermal.thermal_bc = "via System Coupling"
 
-# add two Fluent sessions above as participants
-fluid_name = syc.setup.add_participant(participant_session=pipe_fluid_session)
-solid_name = syc.setup.add_participant(participant_session=pipe_solid_session)
-syc.setup.coupling_participant[fluid_name].display_name = "Fluid"
-syc.setup.coupling_participant[solid_name].display_name = "Solid"
+fluent.solution.run_calculation.iter_count = 20
 
-# add a coupling interface
-interface = syc.setup.add_interface(
-    side_one_participant=fluid_name,
-    side_one_regions=["wall"],
-    side_two_participant=solid_name,
-    side_two_regions=["inner_wall"],
+# %%
+# Set up the coupled analysis
+# ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+# System Coupling setup involves adding the structural and fluid
+# participants, adding coupled interfaces and data transfers,
+# and setting other coupled analysis properties.
+syc=pysyc.launch(start_output= True)
+
+#%%
+# Add participants by passing session handles to System Coupling.
+fluid_name=syc.setup.add_participant(participant_session= fluent)
+solid_name=syc.setup.add_participant(participant_session= mapdl)
+
+syc.setup.coupling_participant[fluid_name].display_name= "Fluid"
+syc.setup.coupling_participant[solid_name].display_name= "Solid"
+
+#%%
+#Add coupling face and data transfers
+interface_name=syc.setup.add_interface(
+    side_one_participant= fluid_name, side_one_regions= ["inner_wall"],
+    side_two_participant= solid_name, side_two_regions= ["FSIN_1"]
 )
 
-# set up 2-way coupling - add temperature and heat flow data transfers
-syc.setup.add_thermal_data_transfers(interface=interface)
+#%%
+#Set up 2-way thermal FSI coupling
+syc.setup.add_thermal_data_transfers(interface = interface_name)
 
-# set up coupled analysis settings
-# it should take about 80 iterations to converge
-syc.setup.solution_control.maximum_iterations = 100
+# %%
+# Time step size, end time, output controls
+syc.setup.solution_control.time_step_size = "0.1 [s]"  # time step is 0.1 [s]
+syc.setup.solution_control.end_time = 10  # end time is 10.0 [s]
 
-# ===
+syc.setup.solution_control.maximum_iterations=100
 
-# solve the coupled analysis
+# %%
+# Solution
+# --------
 syc.solution.solve()
 
-# ===
-
-# clean up at the end
+# %%
+# Exit
+# ----
 syc.end_output()
-pipe_fluid_session.exit()
-pipe_solid_session.exit()
 syc.exit()
+