Beispiel #1
0
    def j(self, m):
        ''' This memoised function returns the functional value for the parameter choice m. '''
        info_green('Start evaluation of j')
        timer = dolfin.Timer("j evaluation")
        j = self.compute_functional_mem(m)
        timer.stop()

        if self.__config__.params["save_checkpoints"]:
            self.save_checkpoint("checkpoint")

        if self.plot:
            self.plotter.addPoint(j)
            self.plotter.savefig("functional_plot.png")
        info_blue('Runtime: ' + str(timer.value()) + " s")
        info_green('j = ' + str(j))

        if self.__config__.params['automatic_scaling']:
            if not self.automatic_scaling_factor:
                # Computing dj will set the automatic scaling factor.
                info_blue(
                    "Computing derivative to determine the automatic scaling factor"
                )
                dj = self.dj(m, forget=False)
            return j * self.scale * self.automatic_scaling_factor
        else:
            return j * self.scale
    def dj(self, m, forget, optimisation_iteration=True):
        ''' This memoised function returns the gradient of the functional for the parameter choice m. '''
        info_green('Start evaluation of dj')
        timer = dolfin.Timer("dj evaluation")
        dj = self.compute_gradient_mem(m, forget)

        # We assume that the gradient is computed at and only at the beginning of each new optimisation iteration.
        # Hence, this is the right moment to store the turbine friction field and to increment the optimisation iteration
        # counter.
        if optimisation_iteration:
            self.__config__.optimisation_iteration += 1
            if self.__config__.params["dump_period"] > 0:
                # A cache hit skips the turbine cache update, so we need
                # trigger it manually.
                if self.compute_gradient_mem.has_cache(m, forget):
                    self.update_turbine_cache(m)
                if "dynamic_turbine_friction" in self.__config__.params["controls"]:
                    info_red("Turbine VTU output not yet implemented for dynamic turbine control")
                else:
                    self.turbine_file << self.__config__.turbine_cache.cache["turbine_field"]
                    # Compute the total amount of friction due to turbines
                    if self.__config__.params["turbine_parametrisation"] == "smeared":
                        print "Total amount of friction: ", assemble(self.__config__.turbine_cache.cache["turbine_field"] * dx)

        if self.save_functional_values and MPI.process_number() == 0:
            with open("functional_values.txt", "a") as functional_values:
                functional_values.write(str(self.last_j) + "\n")

        if self.plot:
            self.plotter.addPoint(self.last_j)
            self.plotter.savefig("functional_plot.png")

        if self.__config__.params["save_checkpoints"]:
            self.save_checkpoint("checkpoint")

        # Compute the scaling factor if never done before
        if self.__config__.params['automatic_scaling'] and not self.automatic_scaling_factor:
            if not 'turbine_pos' in self.__config__.params['controls']:
                raise NotImplementedError("Automatic scaling only works if the turbine positions are control parameters")

            if len(self.__config__.params['controls']) > 1:
                assert(len(dj) % 3 == 0)
                # Exclude the first third from the automatic scaling as it contains the friction coefficients
                djl2 = max(abs(dj[len(dj) / 3:]))
            else:
                djl2 = max(abs(dj))

            if djl2 == 0:
                raise ValueError("Automatic scaling failed: The gradient at the parameter point is zero")
            else:
                self.automatic_scaling_factor = abs(self.__config__.params['automatic_scaling_multiplier'] * max(self.__config__.params['turbine_x'], self.__config__.params['turbine_y']) / djl2 / self.scale)
                info_blue("The automatic scaling factor was set to " + str(self.automatic_scaling_factor * self.scale) + ".")

        info_blue('Runtime: ' + str(timer.stop()) + " s")
        info_green('|dj| = ' + str(numpy.linalg.norm(dj)))

        if self.__config__.params['automatic_scaling']:
            return dj * self.scale * self.automatic_scaling_factor
        else:
            return dj * self.scale
Beispiel #3
0
    def dj(self, m, forget):
        ''' This memoised function returns the gradient of the functional for the parameter choice m. '''
        info_green('Start evaluation of dj')
        timer = dolfin.Timer("dj evaluation")
        dj = self.compute_gradient_mem(m, forget)

        # We assume that at the gradient is computed if and only if at the beginning of each new optimisation iteration.
        # Hence, let this is the right moment to store the turbine friction field.
        if self.__config__.params["dump_period"] > 0:
            # A cache hit skips the turbine cache update, so we need
            # trigger it manually.
            if self.compute_gradient_mem.has_cache(m, forget):
                self.update_turbine_cache(m)
            if "dynamic_turbine_friction" in self.__config__.params[
                    "controls"]:
                info_red(
                    "Turbine VTU output not yet implemented for dynamic turbine control"
                )
            else:
                self.turbine_file << self.__config__.turbine_cache.cache[
                    "turbine_field"]

        if self.__config__.params["save_checkpoints"]:
            self.save_checkpoint("checkpoint")

        # Compute the scaling factor if never done before
        if self.__config__.params[
                'automatic_scaling'] and not self.automatic_scaling_factor:
            if not 'turbine_pos' in self.__config__.params['controls']:
                raise NotImplementedError, "Automatic scaling only works if the turbine positions are control parameters"

            if len(self.__config__.params['controls']) > 1:
                assert (len(dj) % 3 == 0)
                # Exclude the first third from the automatic scaling as it contains the friction coefficients
                djl2 = max(abs(dj[len(dj) / 3:]))
            else:
                djl2 = max(abs(dj))

            if djl2 == 0:
                raise ValueError, "Automatic scaling failed: The gradient at the parameter point is zero"
            else:
                self.automatic_scaling_factor = abs(
                    self.__config__.params['automatic_scaling_multiplier'] *
                    max(self.__config__.params['turbine_x'],
                        self.__config__.params['turbine_y']) / djl2 /
                    self.scale)
                info_blue("The automatic scaling factor was set to " +
                          str(self.automatic_scaling_factor * self.scale) +
                          ".")

        info_blue('Runtime: ' + str(timer.stop()) + " s")
        info_green('|dj| = ' + str(numpy.linalg.norm(dj)))

        if self.__config__.params['automatic_scaling']:
            return dj * self.scale * self.automatic_scaling_factor
        else:
            return dj * self.scale
    def dj_with_check(self, m, seed=0.1, tol=1.8, forget=True):
        ''' This function checks the correctness and returns the gradient of the functional for the parameter choice m. '''

        info_red("Checking derivative at m = " + str(m))
        p = numpy.random.rand(len(m))
        minconv = helpers.test_gradient_array(self.j, self.dj, m, seed=seed, perturbation_direction=p)
        if minconv < tol:
            info_red("The gradient taylor remainder test failed.")
            sys.exit(1)
        else:
            info_green("The gradient taylor remainder test passed.")

        return self.dj(m, forget)
    def dj(self, m, forget):
        ''' This memoised function returns the gradient of the functional for the parameter choice m. '''
        info_green('Start evaluation of dj')
        timer = dolfin.Timer("dj evaluation") 
        dj = self.compute_gradient_mem(m, forget)

        # We assume that at the gradient is computed if and only if at the beginning of each new optimisation iteration.
        # Hence, let this is the right moment to store the turbine friction field. 
        if self.__config__.params["dump_period"] > 0:
            # A cache hit skips the turbine cache update, so we need 
            # trigger it manually.
            if self.compute_gradient_mem.has_cache(m, forget):
                self.update_turbine_cache(m)
            if "dynamic_turbine_friction" in self.__config__.params["controls"]:
                info_red("Turbine VTU output not yet implemented for dynamic turbine control")
            else:    
                self.turbine_file << self.__config__.turbine_cache.cache["turbine_field"] 

        if self.__config__.params["save_checkpoints"]:
            self.save_checkpoint("checkpoint")

        # Compute the scaling factor if never done before
        if self.__config__.params['automatic_scaling'] and not self.automatic_scaling_factor:
            if not 'turbine_pos' in self.__config__.params['controls']:
                raise NotImplementedError, "Automatic scaling only works if the turbine positions are control parameters"

            if len(self.__config__.params['controls']) > 1:
                assert(len(dj) % 3 == 0)
                # Exclude the first third from the automatic scaling as it contains the friction coefficients
                djl2 = max(abs(dj[len(dj)/3:]))
            else:
                djl2 = max(abs(dj))

            if djl2 == 0:
                raise ValueError, "Automatic scaling failed: The gradient at the parameter point is zero"
            else:
                self.automatic_scaling_factor = abs(self.__config__.params['automatic_scaling_multiplier'] * max(self.__config__.params['turbine_x'], self.__config__.params['turbine_y']) / djl2 / self.scale)
                info_blue("The automatic scaling factor was set to " + str(self.automatic_scaling_factor * self.scale) + ".")

        info_blue('Runtime: ' + str(timer.stop())  + " s")
        info_green('|dj| = ' + str(numpy.linalg.norm(dj)))

        if self.__config__.params['automatic_scaling']:
            return dj * self.scale * self.automatic_scaling_factor
        else:
            return dj * self.scale
Beispiel #6
0
    def dj_with_check(self, m, seed=0.1, tol=1.8, forget=True):
        ''' This function checks the correctness and returns the gradient of the functional for the parameter choice m. '''

        info_red("Checking derivative at m = " + str(m))
        p = numpy.random.rand(len(m))
        minconv = helpers.test_gradient_array(self.j,
                                              self.dj,
                                              m,
                                              seed=seed,
                                              perturbation_direction=p)
        if minconv < tol:
            info_red("The gradient taylor remainder test failed.")
            sys.exit(1)
        else:
            info_green("The gradient taylor remainder test passed.")

        return self.dj(m, forget)
    def j(self, m, annotate=True):
        ''' This memoised function returns the functional value for the parameter choice m. '''
        info_green('Start evaluation of j')
        timer = dolfin.Timer("j evaluation")
        j = self.compute_functional_mem(m, annotate=annotate)
        timer.stop()

        if self.__config__.params["save_checkpoints"]:
            self.save_checkpoint("checkpoint")

        info_blue('Runtime: ' + str(timer.value()) + " s")
        info_green('j = ' + str(j))
        self.last_j = j

        if self.__config__.params['automatic_scaling']:
            if not self.automatic_scaling_factor:
                # Computing dj will set the automatic scaling factor.
                info_blue("Computing derivative to determine the automatic scaling factor")
                self.dj(m, forget=False, optimisation_iteration=False)
            return j * self.scale * self.automatic_scaling_factor
        else:
            return j * self.scale
def sw_solve(config, state, turbine_field=None, functional=None, annotate=True, u_source=None):
    '''Solve the shallow water equations with the parameters specified in params.
       Options for linear_solver and preconditioner are:
        linear_solver: lu, cholesky, cg, gmres, bicgstab, minres, tfqmr, richardson
        preconditioner: none, ilu, icc, jacobi, bjacobi, sor, amg, additive_schwarz, hypre_amg, hypre_euclid, hypre_parasails, ml_amg
    '''

    ############################### Setting up the equations ###########################

    # Define variables for all used parameters
    ds = config.domain.ds
    params = config.params

    # To begin with, check if the provided parameters are valid
    params.check()

    theta = params["theta"]
    dt = params["dt"]
    g = params["g"]
    depth = params["depth"]
    # Reset the time
    params["current_time"] = params["start_time"]
    t = params["current_time"]
    quadratic_friction = params["quadratic_friction"]
    include_advection = params["include_advection"]
    include_diffusion = params["include_diffusion"]
    include_time_term = params["include_time_term"]
    diffusion_coef = params["diffusion_coef"]
    newton_solver = params["newton_solver"]
    picard_relative_tolerance = params["picard_relative_tolerance"]
    picard_iterations = params["picard_iterations"]
    linear_solver = params["linear_solver"]
    preconditioner = params["preconditioner"]
    bctype = params["bctype"]
    strong_bc = params["strong_bc"]
    free_slip_on_sides = params["free_slip_on_sides"]
    steady_state = params["steady_state"]
    functional_final_time_only = params["functional_final_time_only"]
    functional_quadrature_degree = params["functional_quadrature_degree"]
    is_nonlinear = (include_advection or quadratic_friction)
    turbine_thrust_parametrisation = params["turbine_thrust_parametrisation"]
    implicit_turbine_thrust_parametrisation = params["implicit_turbine_thrust_parametrisation"]
    cache_forward_state = params["cache_forward_state"]

    if not 0 <= functional_quadrature_degree <= 1:
        raise ValueError("functional_quadrature_degree must be 0 or 1.")

    if implicit_turbine_thrust_parametrisation:
        function_space = config.function_space_2enriched
    elif turbine_thrust_parametrisation:
        function_space = config.function_space_enriched
    else:
        function_space = config.function_space

    # Take care of the steady state case
    if steady_state:
        dt = 1.
        params["finish_time"] = params["start_time"] + dt / 2
        theta = 1.

    # Define test functions
    if implicit_turbine_thrust_parametrisation:
        v, q, o, o_adv = TestFunctions(function_space)
    elif turbine_thrust_parametrisation:
        v, q, o = TestFunctions(function_space)
    else:
        v, q = TestFunctions(function_space)

    # Define functions
    state_new = Function(function_space, name="New_state")  # solution of the next timestep
    state_nl = Function(function_space, name="Best_guess_state")  # the last computed state of the next timestep, used for the picard iteration

    if not newton_solver and (turbine_thrust_parametrisation or implicit_turbine_thrust_parametrisation):
        raise NotImplementedError("Thrust turbine representation does currently only work with the newton solver.")

    # Split mixed functions
    if is_nonlinear and newton_solver:
        if implicit_turbine_thrust_parametrisation:
            u, h, up_u, up_u_adv = split(state_new)
        elif turbine_thrust_parametrisation:
            u, h, up_u = split(state_new)
        else:
            u, h = split(state_new)
    else:
        u, h = TrialFunctions(function_space)

    if implicit_turbine_thrust_parametrisation:
        u0, h0, up_u0, up_u_adv0 = split(state)
    elif turbine_thrust_parametrisation:
        u0, h0, up_u0 = split(state)
    else:
        u0, h0 = split(state)
        u_nl, h_nl = split(state_nl)

    # Create initial conditions and interpolate
    state_new.assign(state, annotate=annotate)

    # u_(n+theta) and h_(n+theta)
    u_mid = (1.0 - theta) * u0 + theta * u
    h_mid = (1.0 - theta) * h0 + theta * h

    # If a picard iteration is used we need an intermediate state
    if is_nonlinear and not newton_solver:
        u_nl, h_nl = split(state_nl)
        state_nl.assign(state, annotate=annotate)
        u_mid_nl = (1.0 - theta) * u0 + theta * u_nl

    # The normal direction
    n = FacetNormal(function_space.mesh())

    # Mass matrix

    M = inner(v, u) * dx
    M += inner(q, h) * dx
    M0 = inner(v, u0) * dx
    M0 += inner(q, h0) * dx

    # Divergence term.
    Ct_mid = -depth * inner(u_mid, grad(q)) * dx
    #+inner(avg(u_mid),jump(q,n))*dS # This term is only needed for dg element pairs

    if bctype == 'dirichlet':
        if steady_state:
            raise ValueError("Can not use a time dependent boundary condition for a steady state simulation")
        # The dirichlet boundary condition on the left hand side
        expr = config.params["weak_dirichlet_bc_expr"]
        bc_contr = - depth * dot(expr, n) * q * ds(1)

        # The dirichlet boundary condition on the right hand side
        bc_contr -= depth * dot(expr, n) * q * ds(2)

        # We enforce a no-normal flow on the sides by removing the surface integral.
        # bc_contr -= dot(u_mid, n) * q * ds(3)

    elif bctype == 'flather':
        if steady_state:
            raise ValueError("Can not use a time dependent boundary condition for a steady state simulation")
        # The Flather boundary condition on the left hand side
        expr = config.params["flather_bc_expr"]
        bc_contr = - depth * dot(expr, n) * q * ds(1)
        Ct_mid += sqrt(g * depth) * inner(h_mid, q) * ds(1)

        # The contributions of the Flather boundary condition on the right hand side
        Ct_mid += sqrt(g * depth) * inner(h_mid, q) * ds(2)

    elif bctype == 'strong_dirichlet':
        # Do not replace anything in the surface integrals as the strong Dirichlet Boundary condition will do that
        bc_contr = -depth * dot(u_mid, n) * q * ds(1)
        bc_contr -= depth * dot(u_mid, n) * q * ds(2)
        if not free_slip_on_sides:
            bc_contr -= depth * dot(u_mid, n) * q * ds(3)

    else:
        info_red("Unknown boundary condition type: %s" % bctype)
        sys.exit(1)

    # Pressure gradient operator
    C_mid = g * inner(v, grad(h_mid)) * dx
    #+inner(avg(v),jump(h_mid,n))*dS # This term is only needed for dg element pairs

    # Bottom friction
    friction = params["friction"]

    if turbine_field:
        if type(turbine_field) == list:
            tf = Function(turbine_field[0], name="turbine_friction", annotate=annotate)
        else:
            tf = Function(turbine_field, name="turbine_friction", annotate=annotate)

        if turbine_thrust_parametrisation or implicit_turbine_thrust_parametrisation:
            print0("Adding thrust force")
            # Compute the upstream velocities

            if implicit_turbine_thrust_parametrisation:
                up_u_eq = upstream_u_implicit_equation(config, tf, u, up_u, o, up_u_adv, o_adv)
            elif turbine_thrust_parametrisation:
                up_u_eq = upstream_u_equation(config, tf, u, up_u, o)

            def thrust_force(up_u, min=smooth_uflmin):
                ''' Returns the thrust force for a given upstream velcocity '''
                # Now apply a pointwise transformation based on the interpolation of a loopup table
                c_T_coeffs = [0.08344535, -1.42428216, 9.13153605, -26.19370168, 28.8752054]
                c_T_coeffs.reverse()
                c_T = min(0.88, sum([c_T_coeffs[i] * up_u ** i for i in range(len(c_T_coeffs))]))

                # The amount of forcing we want to apply
                turbine_radius = 15.
                A_c = pi * Constant(turbine_radius ** 2)  # Turbine cross section
                f = 0.5 * c_T * up_u ** 2 * A_c
                return f

            # Apply the force in the opposite direction of the flow
            f_dir = -thrust_force(up_u) * u / norm_approx(u, alpha=1e-6)
            # Distribute this force over the turbine area
            thrust = inner(f_dir * tf / (Constant(config.turbine_cache.turbine_integral()) * config.params["depth"]), v) * dx

    # Friction term
    # With Newton we can simply use a non-linear form
    if quadratic_friction and newton_solver:
        R_mid = friction / depth * dot(u_mid, u_mid) ** 0.5 * inner(u_mid, v) * dx

        if turbine_field and not (turbine_thrust_parametrisation or implicit_turbine_thrust_parametrisation):
            R_mid += tf / depth * dot(u_mid, u_mid) ** 0.5 * inner(u_mid, v) * config.site_dx(1)

    # With a picard iteration we need to linearise using the best guess
    elif quadratic_friction and not newton_solver:
        R_mid = friction / depth * dot(u_mid_nl, u_mid_nl) ** 0.5 * inner(u_mid, v) * dx

        if turbine_field and not (turbine_thrust_parametrisation or implicit_turbine_thrust_parametrisation):
            R_mid += tf / depth * dot(u_mid_nl, u_mid_nl) ** 0.5 * inner(u_mid, v) * config.site_dx(1)

    # Use a linear drag
    else:
        R_mid = friction / depth * inner(u_mid, v) * dx

        if turbine_field and not (turbine_thrust_parametrisation or implicit_turbine_thrust_parametrisation):
            R_mid += tf / depth * inner(u_mid, v) * config.site_dx(1)

    # Advection term
    # With a newton solver we can simply use a quadratic form
    if include_advection and newton_solver:
        Ad_mid = inner(dot(grad(u_mid), u_mid), v) * dx
    # With a picard iteration we need to linearise using the best guess
    if include_advection and not newton_solver:
        Ad_mid = inner(dot(grad(u_mid), u_mid_nl), v) * dx

    if include_diffusion:
        # Check that we are not using a DG velocity function space, as the facet integrals are not implemented.
        if "Discontinuous" in str(function_space.split()[0]):
            raise NotImplementedError("The diffusion term for discontinuous elements is not implemented yet.")
        D_mid = diffusion_coef * inner(grad(u_mid), grad(v)) * dx

    # Create the final form
    G_mid = C_mid + Ct_mid + R_mid
    # Add the advection term
    if include_advection:
        G_mid += Ad_mid
    # Add the diffusion term
    if include_diffusion:
        G_mid += D_mid
    # Add the source term
    if u_source:
        G_mid -= inner(u_source, v) * dx
    F = dt * G_mid - dt * bc_contr
    # Add the time term
    if include_time_term and not steady_state:
        F += M - M0

    if turbine_thrust_parametrisation or implicit_turbine_thrust_parametrisation:
        F += up_u_eq
        if turbine_field:
            F -= thrust

    # Preassemble the lhs if possible
    use_lu_solver = (linear_solver == "lu")
    if not is_nonlinear:
        lhs_preass = assemble(dolfin.lhs(F))
        # Precompute the LU factorisation
        if use_lu_solver:
            info("Computing the LU factorisation for later use ...")
            if bctype == 'strong_dirichlet':
                raise NotImplementedError("Strong boundary condition and reusing LU factorisation is currently not implemented")
            lu_solver = LUSolver(lhs_preass)
            lu_solver.parameters["reuse_factorization"] = True

    solver_parameters = {"linear_solver": linear_solver, "preconditioner": preconditioner}

    # Do some parameter checking:
    if "dynamic_turbine_friction" in params["controls"]:
        if len(config.params["turbine_friction"]) != (params["finish_time"] - t) / dt + 1:
            print0("You control the turbine friction dynamically, but your turbine friction parameter is not an array of length 'number of timesteps' (here: %i)." % ((params["finish_time"] - t) / dt + 1))
            import sys
            sys.exit(1)

    ############################### Perform the simulation ###########################

    if params["dump_period"] > 0:
        try:
            statewriter_cb = config.statewriter_callback
        except AttributeError:
            statewriter_cb = None 

        writer = StateWriter(config, optimisation_iteration=config.optimisation_iteration, callback=statewriter_cb)
        if not steady_state and include_time_term:
            print0("Writing state to disk...")
            writer.write(state)

    step = 0

    if functional is not None:
        if steady_state or functional_final_time_only:
            j = 0.
            if params["print_individual_turbine_power"]:
                j_individual = [0] * len(params["turbine_pos"])
                force_individual = [0] * len(params["turbine_pos"])

        else:
            if functional_quadrature_degree == 0:
                quad = 0.0
            else:
                quad = 0.5
            j = dt * quad * assemble(functional.Jt(state, tf))
            if params["print_individual_turbine_power"]:
                j_individual = []
                force_individual = []
                for i in range(len(params["turbine_pos"])):
                    j_individual.append(dt * quad * assemble(functional.Jt_individual(state, i)))
                    force_individual.append(dt * quad * assemble(functional.force_individual(state, i)))

    print0("Start of time loop")
    adjointer.time.start(t)
    timestep = 0
    while (t < params["finish_time"]):
        timestep += 1
        t += dt
        params["current_time"] = t

        # Update bc's
        if bctype == "strong_dirichlet":
            strong_bc.update_time(t)
        else:
            expr.t = t - (1.0 - theta) * dt
        # Update source term
        if u_source:
            u_source.t = t - (1.0 - theta) * dt
        step += 1

        # Solve non-linear system with a Newton sovler
        if is_nonlinear and newton_solver:
            # Use a Newton solver to solve the nonlinear problem.
            #solver_parameters["linear_solver"] = "gmres"
            #solver_parameters["linear_solver"] = "superlu_dist"
            #solver_parameters["preconditioner"] = "ilu" # does not work in parallel
            #solver_parameters["preconditioner"] = "amg"
            #solver_parameters["linear_solver"] = "mumps"
            #solver_parameters["linear_solver"] = "umfpack"
            solver_parameters["newton_solver"] = {}
            solver_parameters["newton_solver"]["error_on_nonconvergence"] = True
            solver_parameters["newton_solver"]["maximum_iterations"] = 20
            solver_parameters["newton_solver"]["convergence_criterion"] = "incremental"
            solver_parameters["newton_solver"]["relative_tolerance"] = 1e-16

            if cache_forward_state and state_cache.has_key(t):
                print0("Load initial guess from cache for time %f." % t)
                # Load initial guess for solver from cache
                state_new.assign(state_cache[t], annotate=False)
            elif not include_time_term:
                print0("Set the initial guess for the nonlinear solver to the initial condition.")
                # Reset the initial guess after each timestep
                ic = config.params['initial_condition']
                state_new.assign(ic, annotate=False)

            info_blue("Solve shallow water equations at time %s (Newton iteration) ..." % params["current_time"])
            if bctype == 'strong_dirichlet':
                solve(F == 0, state_new, bcs=strong_bc.bcs, solver_parameters=solver_parameters, annotate=annotate)
            else:
                solve(F == 0, state_new, solver_parameters=solver_parameters, annotate=annotate)

            if turbine_thrust_parametrisation or implicit_turbine_thrust_parametrisation:
                print0("Inflow velocity: ", u[0]((10, 160)))
                print0("Estimated upstream velocity: ", up_u((640. / 3, 160)))
                print0("Expected thrust force: ", thrust_force(u[0]((10, 160)), min=min)((0)))
                print0("Total amount of thurst force applied: ", assemble(inner(Constant(1), thrust_force(up_u) * tf / config.turbine_cache.turbine_integral()) * dx))

                us.append(u[0]((10, 160)))
                thrusts.append(thrust_force(u[0]((10, 160)))((0)))
                thrusts_est.append(assemble(inner(Constant(1), thrust_force(up_u) * tf / config.turbine_cache.turbine_integral()) * dx))

                import matplotlib.pyplot as plt
                plt.clf()
                plt.plot(us, thrusts, label="Analytical")
                plt.plot(us, thrusts_est, label="Approximated")
                plt.legend(loc=2)
                plt.savefig("thrust_plot.pdf", format='pdf')

        # Solve non-linear system with a Picard iteration
        elif is_nonlinear:
            # Solve the problem using a picard iteration
            iter_counter = 0
            while True:
                info_blue("Solving shallow water equations at time %s (Picard iteration %d) ..." % (params["current_time"], iter_counter))
                if bctype == 'strong_dirichlet':
                    solve(dolfin.lhs(F) == dolfin.rhs(F), state_new, bcs=strong_bc.bcs, solver_parameters=solver_parameters)
                else:
                    solve(dolfin.lhs(F) == dolfin.rhs(F), state_new, solver_parameters=solver_parameters, annotate=annotate)
                iter_counter += 1
                if iter_counter > 0:
                    relative_diff = abs(assemble(inner(state_new - state_nl, state_new - state_nl) * dx)) / assemble(inner(state_new, state_new) * dx)
                    info_blue("Picard iteration " + str(iter_counter) + " relative difference: " + str(relative_diff))

                    if relative_diff < picard_relative_tolerance:
                        info("Picard iteration converged after " + str(iter_counter) + " iterations.")
                        break
                    elif iter_counter >= picard_iterations:
                        info_red("Picard iteration reached maximum number of iterations (" + str(picard_iterations) + ") with a relative difference of " + str(relative_diff) + ".")
                        break

            state_nl.assign(state_new)

        # Solve linear system with preassembled matrices
        else:
            # dolfin can't assemble empty forms which can sometimes happen here.
            # A simple workaround is to add a dummy term:
            dummy_term = Constant(0) * q * dx
            rhs_preass = assemble(dolfin.rhs(F + dummy_term))
            # Apply dirichlet boundary conditions
            info_blue("Solving shallow water equations at time %s (preassembled matrices) ..." % (params["current_time"]))
            if bctype == 'strong_dirichlet':
                [bc.apply(lhs_preass, rhs_preass) for bc in strong_bc.bcs]
            if use_lu_solver:
                info("Using a LU solver to solve the linear system.")
                lu_solver.solve(state.vector(), rhs_preass, annotate=annotate)
            else:
                solve(lhs_preass, state_new.vector(), rhs_preass, solver_parameters["linear_solver"], solver_parameters["preconditioner"], annotate=annotate)

        # After the timestep solve, update state
        state.assign(state_new)
        if cache_forward_state:
            # Save state for initial guess cache
            print0("Cache initial guess for time %f." % t)
            if not state_cache.has_key(t):
                state_cache[t] = Function(state_new.function_space())
            state_cache[t].assign(state_new, annotate=False)

        # Set the control function for the upcoming timestep.
        if turbine_field:
            if type(turbine_field) == list:
                tf.assign(turbine_field[timestep])
            else:
                tf.assign(turbine_field)

        if params["dump_period"] > 0 and step % params["dump_period"] == 0:
            print0("Write state to disk...")
            writer.write(state)

        if functional is not None:
            if not (functional_final_time_only and t < params["finish_time"]):
                if steady_state or functional_final_time_only or functional_quadrature_degree == 0:
                    quad = 1.0
                elif t >= params["finish_time"]:
                    quad = 0.5 * dt
                else:
                    quad = 1.0 * dt

                j += quad * assemble(functional.Jt(state, tf))
                if params["print_individual_turbine_power"]:
                    info_green("Computing individual turbine power extraction contribution...")
                    individual_contribution_list = ['x_pos', 'y_pos', 'turbine_power', 'total_force_on_turbine', 'turbine_friction']
                    fr_individual = range(len(params["turbine_pos"]))
                    for i in range(len(params["turbine_pos"])):
                        j_individual[i] += dt * quad * assemble(functional.Jt_individual(state, i))
                        force_individual[i] += dt * quad * assemble(functional.force_individual(state, i))

                        if len(params["turbine_friction"]) > 0:
                            fr_individual[i] = params["turbine_friction"][i]
                        else:
                            fr_individual = [params["turbine_friction"]] * len(params["turbine_pos"])

                        individual_contribution_list.append((params["turbine_pos"][i])[0])
                        individual_contribution_list.append((params["turbine_pos"][i])[1])
                        individual_contribution_list.append(j_individual[i])
                        individual_contribution_list.append(force_individual[i])
                        individual_contribution_list.append(fr_individual[i])

                        print0("Contribution of turbine number %d at co-ordinates:" % (i + 1), params["turbine_pos"][i], ' is: ', j_individual[i] * 0.001, 'kW', 'with friction of', fr_individual[i])

        # Increase the adjoint timestep
        adj_inc_timestep(time=t, finished=(not t < params["finish_time"]))
    print0("End of time loop.")

    # Write the turbine positions, power extraction and friction to a .csv file named turbine_info.csv
    if params['print_individual_turbine_power']:
        f = config.params['base_path'] + os.path.sep + "iter_" + str(config.optimisation_iteration) + '/'
        # Save the very first result in a different file
        if config.optimisation_iteration == 0 and not os.path.isfile(f):
            f += 'initial_turbine_info.csv'
        else:
            f += 'turbine_info.csv'

        output_turbines = open(f, 'w')
        for i in range(0, len(individual_contribution_list), 5):
            print >> output_turbines, '%s, %s, %s, %s, %s' % (individual_contribution_list[i], individual_contribution_list[i + 1], individual_contribution_list[i + 2], individual_contribution_list[i + 3], individual_contribution_list[i + 4])
        print 'Total of individual turbines is', sum(j_individual)

    if functional is not None:
        return j
Beispiel #9
0
    def update(self, config):
        ''' Creates a list of all turbine function/derivative interpolations. This list is used as a cache
          to avoid the recomputation of the expensive interpolation of the turbine expression. '''

        # If the parameters have not changed, then there is no need to do anything
        if self.params is not None:

            if (len(self.params["turbine_friction"]) == len(config.params["turbine_friction"]) and
               len(self.params["turbine_pos"]) == len(config.params["turbine_pos"]) and
               (self.params["turbine_friction"] == config.params["turbine_friction"]).all() and
               (self.params["turbine_pos"] == config.params["turbine_pos"]).all()):
                return

        if config.params["turbine_parametrisation"] == "smeared":
            tf = Function(config.turbine_function_space, name="turbine_friction_cache")

            optimization.set_local(tf, config.params["turbine_friction"])
            self.cache["turbine_field"] = tf
            return

        info_green("Updating turbine cache")

        # Store the new turbine parameters
        self.params = ParameterDictionary(config.params)
        self.params["turbine_friction"] = numpy.copy(config.params["turbine_friction"])
        self.params["turbine_pos"] = numpy.copy(config.params["turbine_pos"])

        # Precompute the interpolation of the friction function of all turbines
        turbines = Turbines(config.turbine_function_space, self.params)

        if "dynamic_turbine_friction" in self.params["controls"]:
            # If the turbine friction is controlled dynamically, we need to cache the turbine
            # field for every timestep
            self.cache["turbine_field"] = []
            for t in range(len(self.params["turbine_friction"])):
                tf = turbines(name="turbine_friction_cache_t_" + str(t), timestep=t)
                self.cache["turbine_field"].append(tf)
        else:
            tf = turbines(name="turbine_friction_cache")
            self.cache["turbine_field"] = tf

        # Precompute the interpolation of the friction function for each individual turbine
        if self.params["print_individual_turbine_power"]:
            info_green("Building individual turbine power friction functions for caching purposes...")
            self.cache["turbine_field_individual"] = []
            for i in range(len(self.params["turbine_friction"])):
                params_cpy = ParameterDictionary(self.params)
                params_cpy["turbine_pos"] = [self.params["turbine_pos"][i]]
                params_cpy["turbine_friction"] = [self.params["turbine_friction"][i]]
                turbine = Turbines(config.turbine_function_space, params_cpy)
                tf = turbine()
                self.cache["turbine_field_individual"].append(tf)

        # Precompute the derivatives with respect to the friction magnitude of each turbine
        if "turbine_friction" in self.params["controls"]:
            self.cache["turbine_derivative_friction"] = []
            for n in range(len(self.params["turbine_friction"])):
                tfd = turbines(derivative_index_selector=n,
                               derivative_var_selector='turbine_friction',
                               name="turbine_friction_derivative_with_respect_friction_magnitude_of_turbine_" + str(n))
                self.cache["turbine_derivative_friction"].append(tfd)

        elif "dynamic_turbine_friction" in self.params["controls"]:
            self.cache["turbine_derivative_friction"] = []
            for t in range(len(self.params["turbine_friction"])):
                self.cache["turbine_derivative_friction"].append([])

                for n in range(len(self.params["turbine_friction"][t])):
                    tfd = turbines(derivative_index_selector=n,
                                   derivative_var_selector='turbine_friction',
                                   name="turbine_friction_derivative_with_respect_friction_magnitude_of_turbine_" + str(n) + "t_" + str(t),
                                   timestep=t)
                    self.cache["turbine_derivative_friction"][t].append(tfd)

        # Precompute the derivatives with respect to the turbine position
        if "turbine_pos" in self.params["controls"]:

            if not "dynamic_turbine_friction" in self.params["controls"]:
                self.cache["turbine_derivative_pos"] = []
                for n in range(len(self.params["turbine_pos"])):
                    self.cache["turbine_derivative_pos"].append({})
                    for var in ('turbine_pos_x', 'turbine_pos_y'):
                        tfd = turbines(derivative_index_selector=n,
                                       derivative_var_selector=var,
                                       name="turbine_friction_derivative_with_respect_position_of_turbine_" + str(n))
                        self.cache["turbine_derivative_pos"][-1][var] = tfd
            else:
                self.cache["turbine_derivative_pos"] = []

                for t in range(len(self.params["turbine_friction"])):
                    self.cache["turbine_derivative_pos"].append([])

                    for n in range(len(self.params["turbine_pos"])):
                        self.cache["turbine_derivative_pos"][t].append({})
                        for var in ('turbine_pos_x', 'turbine_pos_y'):
                            tfd = turbines(derivative_index_selector=n,
                                           derivative_var_selector=var,
                                           name="turbine_friction_derivative_with_respect_position_of_turbine_" + str(n),
                                           timestep=t)
                            self.cache["turbine_derivative_pos"][t][-1][var] = tfd
Beispiel #10
0
    def update(self, config):
        ''' Creates a list of all turbine function/derivative interpolations. This list is used as a cache 
          to avoid the recomputation of the expensive interpolation of the turbine expression. '''

        # If the parameters have not changed, then there is no need to do anything
        if self.params != None:
            if (self.params["turbine_friction"]
                    == config.params["turbine_friction"]).all() and (
                        self.params["turbine_pos"]
                        == config.params["turbine_pos"]).all():
                return

        if config.params["turbine_parametrisation"] == "smooth":
            tf = Function(config.turbine_function_space,
                          name="turbine_friction_cache")

            optimization.set_local(tf, config.params["turbine_friction"])
            self.cache["turbine_field"] = tf
            return

        info_green("Updating turbine cache")

        # Store the new turbine parameters
        self.params = ParameterDictionary(config.params)
        self.params["turbine_friction"] = numpy.copy(
            config.params["turbine_friction"])
        self.params["turbine_pos"] = numpy.copy(config.params["turbine_pos"])

        # Precompute the interpolation of the friction function of all turbines
        turbines = Turbines(config.turbine_function_space, self.params)

        if "dynamic_turbine_friction" in self.params["controls"]:
            # If the turbine friction is controlled dynamically, we need to cache the turbine
            # field for every timestep
            self.cache["turbine_field"] = []
            for t in range(len(self.params["turbine_friction"])):
                tf = turbines(name="turbine_friction_cache_t_" + str(t),
                              timestep=t)
                self.cache["turbine_field"].append(tf)
        else:
            tf = turbines(name="turbine_friction_cache")
            self.cache["turbine_field"] = tf

        # Precompute the derivatives with respect to the friction magnitude of each turbine
        if "turbine_friction" in self.params["controls"]:
            self.cache["turbine_derivative_friction"] = []
            for n in range(len(self.params["turbine_friction"])):
                tfd = turbines(
                    derivative_index_selector=n,
                    derivative_var_selector='turbine_friction',
                    name=
                    "turbine_friction_derivative_with_respect_friction_magnitude_of_turbine_"
                    + str(n))
                self.cache["turbine_derivative_friction"].append(tfd)

        elif "dynamic_turbine_friction" in self.params["controls"]:
            self.cache["turbine_derivative_friction"] = []
            for t in range(len(self.params["turbine_friction"])):
                self.cache["turbine_derivative_friction"].append([])

                for n in range(len(self.params["turbine_friction"][t])):
                    tfd = turbines(
                        derivative_index_selector=n,
                        derivative_var_selector='turbine_friction',
                        name=
                        "turbine_friction_derivative_with_respect_friction_magnitude_of_turbine_"
                        + str(n) + "t_" + str(t),
                        timestep=t)
                    self.cache["turbine_derivative_friction"][t].append(tfd)

        # Precompute the derivatives with respect to the turbine position
        if "turbine_pos" in self.params["controls"]:

            if not "dynamic_turbine_friction" in self.params["controls"]:
                self.cache["turbine_derivative_pos"] = []
                for n in range(len(self.params["turbine_pos"])):
                    self.cache["turbine_derivative_pos"].append({})
                    for var in ('turbine_pos_x', 'turbine_pos_y'):
                        tfd = turbines(
                            derivative_index_selector=n,
                            derivative_var_selector=var,
                            name=
                            "turbine_friction_derivative_with_respect_position_of_turbine_"
                            + str(n))
                        self.cache["turbine_derivative_pos"][-1][var] = tfd
            else:
                self.cache["turbine_derivative_pos"] = []

                for t in range(len(self.params["turbine_friction"])):
                    self.cache["turbine_derivative_pos"].append([])

                    for n in range(len(self.params["turbine_pos"])):
                        self.cache["turbine_derivative_pos"][t].append({})
                        for var in ('turbine_pos_x', 'turbine_pos_y'):
                            tfd = turbines(
                                derivative_index_selector=n,
                                derivative_var_selector=var,
                                name=
                                "turbine_friction_derivative_with_respect_position_of_turbine_"
                                + str(n),
                                timestep=t)
                            self.cache["turbine_derivative_pos"][t][-1][
                                var] = tfd