Skip to content
Snippets Groups Projects
shearflow.py 7.78 KiB
Newer Older
__copyright__ = "Copyright (C) 2008 Andreas Kloeckner"

__license__ = """
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
"""



from __future__ import division
Andreas Klöckner's avatar
Andreas Klöckner committed
from __future__ import absolute_import
from __future__ import print_function
import numpy
import numpy.linalg as la




class SteadyShearFlow:
    def __init__(self):
        self.gamma = 1.5
        self.mu = 0.01
        self.prandtl = 0.72
        self.spec_gas_const = 287.1

    def __call__(self, t, x_vec):
        # JSH/TW Nodal DG Methods, p.326

        rho = numpy.ones_like(x_vec[0])
        rho_u = x_vec[1] * x_vec[1]
        rho_v = numpy.zeros_like(x_vec[0])
        e = (2 * self.mu * x_vec[0] + 10) / (self.gamma - 1) + x_vec[1]**4 / 2

Andreas Klöckner's avatar
Andreas Klöckner committed
        from grudge.tools import join_fields
        return join_fields(rho, e, rho_u, rho_v)

    def properties(self):
        return(self.gamma, self.mu, self.prandtl, self.spec_gas_const)

    def volume_interpolant(self, t, discr):
        return discr.convert_volume(
                        self(t, discr.nodes.T
                            .astype(discr.default_scalar_type)),
                        kind=discr.compute_kind)

    def boundary_interpolant(self, t, discr, tag):
        result = discr.convert_boundary(
                        self(t, discr.get_boundary(tag).nodes.T
                            .astype(discr.default_scalar_type)),
                        tag=tag, kind=discr.compute_kind)
        return result




def main():
Andreas Klöckner's avatar
Andreas Klöckner committed
    from grudge.backends import guess_run_context
    rcon = guess_run_context(
    #["cuda"]
    )

Andreas Klöckner's avatar
Andreas Klöckner committed
    from grudge.tools import EOCRecorder, to_obj_array
    eoc_rec = EOCRecorder()

    def boundary_tagger(vertices, el, face_nr, all_v):
        return ["inflow"]

    if rcon.is_head_rank:
Andreas Klöckner's avatar
Andreas Klöckner committed
        from grudge.mesh import make_rect_mesh, \
                               make_centered_regular_rect_mesh
        #mesh = make_rect_mesh((0,0), (10,1), max_area=0.01)
        refine = 1
        mesh = make_centered_regular_rect_mesh((0,0), (10,1), n=(20,4),
                            #periodicity=(True, False),
                            post_refine_factor=refine,
                            boundary_tagger=boundary_tagger)
        mesh_data = rcon.distribute_mesh(mesh)
    else:
        mesh_data = rcon.receive_mesh()

    for order in [3]:
        discr = rcon.make_discretization(mesh_data, order=order,
                        default_scalar_type=numpy.float64)

Andreas Klöckner's avatar
Andreas Klöckner committed
        from grudge.visualization import SiloVisualizer, VtkVisualizer
        #vis = VtkVisualizer(discr, rcon, "shearflow-%d" % order)
        vis = SiloVisualizer(discr, rcon)

        shearflow = SteadyShearFlow()
        fields = shearflow.volume_interpolant(0, discr)
        gamma, mu, prandtl, spec_gas_const = shearflow.properties()

Andreas Klöckner's avatar
Andreas Klöckner committed
        from grudge.models.gas_dynamics import GasDynamicsOperator
        op = GasDynamicsOperator(dimensions=2, gamma=gamma, mu=mu,
                prandtl=prandtl, spec_gas_const=spec_gas_const,
                bc_inflow=shearflow, bc_outflow=shearflow, bc_noslip=shearflow,
                inflow_tag="inflow", outflow_tag="outflow", noslip_tag="noslip")

        navierstokes_ex = op.bind(discr)

        max_eigval = [0]
        def rhs(t, q):
            ode_rhs, speed = navierstokes_ex(t, q)
            max_eigval[0] = speed
            return ode_rhs

        # needed to get first estimate of maximum eigenvalue
        rhs(0, fields)

        if rcon.is_head_rank:
Andreas Klöckner's avatar
Andreas Klöckner committed
            print("---------------------------------------------")
            print("order %d" % order)
            print("---------------------------------------------")
            print("#elements=", len(mesh.elements))
Andreas Klöckner's avatar
Andreas Klöckner committed
        from grudge.timestep import RK4TimeStepper
        stepper = RK4TimeStepper()

        # diagnostics setup ---------------------------------------------------
        from logpyle import LogManager, add_general_quantities, \
                add_simulation_quantities, add_run_info

        logmgr = LogManager("navierstokes-cpu-%d-%d.dat" % (order, refine),
                            "w", rcon.communicator)
        add_run_info(logmgr)
        add_general_quantities(logmgr)
        add_simulation_quantities(logmgr)
        discr.add_instrumentation(logmgr)
        stepper.add_instrumentation(logmgr)

        logmgr.add_watches(["step.max", "t_sim.max", "t_step.max"])

        # timestep loop -------------------------------------------------------
        try:
Andreas Klöckner's avatar
Andreas Klöckner committed
            from grudge.timestep import times_and_steps
            step_it = times_and_steps(
                    final_time=0.3,
                    #max_steps=500,
                    logmgr=logmgr,
                    max_dt_getter=lambda t: op.estimate_timestep(discr,
                        stepper=stepper, t=t, max_eigenvalue=max_eigval[0]))

            for step, t, dt in step_it:
                if step % 10 == 0:
                #if False:
                    visf = vis.make_file("shearflow-%d-%04d" % (order, step))

                    #true_fields = shearflow.volume_interpolant(t, discr)

                    from pyvisfile.silo import DB_VARTYPE_VECTOR
                    vis.add_data(visf,
                            [
                                ("rho", discr.convert_volume(op.rho(fields), kind="numpy")),
                                ("e", discr.convert_volume(op.e(fields), kind="numpy")),
                                ("rho_u", discr.convert_volume(op.rho_u(fields), kind="numpy")),
                                ("u", discr.convert_volume(op.u(fields), kind="numpy")),

                                #("true_rho", discr.convert_volume(op.rho(true_fields), kind="numpy")),
                                #("true_e", discr.convert_volume(op.e(true_fields), kind="numpy")),
                                #("true_rho_u", discr.convert_volume(op.rho_u(true_fields), kind="numpy")),
                                #("true_u", discr.convert_volume(op.u(true_fields), kind="numpy")),
                                ],
                            expressions=[
                                #("diff_rho", "rho-true_rho"),
                                #("diff_e", "e-true_e"),
                                #("diff_rho_u", "rho_u-true_rho_u", DB_VARTYPE_VECTOR),

                                ("p", "0.4*(e- 0.5*(rho_u*u))"),
                                ],
                            time=t, step=step
                            )
                    visf.close()

                fields = stepper(fields, t, dt, rhs)

            true_fields = shearflow.volume_interpolant(t, discr)
            l2_error = discr.norm(op.u(fields)-op.u(true_fields))
            eoc_rec.add_data_point(order, l2_error)
Andreas Klöckner's avatar
Andreas Klöckner committed
            print()
            print(eoc_rec.pretty_print("P.Deg.", "L2 Error"))

            logmgr.set_constant("l2_error", l2_error)

        finally:
            vis.close()
            logmgr.save()
            discr.close()

if __name__ == "__main__":
    main()