Example #1
0
def get_context():
    """Set up context for classical (NS) solver"""
    float, complex, mpitype = datatypes(params.precision)
    collapse_fourier = False if params.dealias == '3/2-rule' else True
    dim = len(params.N)
    dtype = lambda d: float if d == dim - 1 else complex
    V = [
        Basis(params.N[i], 'F', domain=(0, params.L[i]), dtype=dtype(i))
        for i in range(dim)
    ]

    kw0 = {
        'threads': params.threads,
        'planner_effort': params.planner_effort['fft']
    }
    T = TensorProductSpace(comm,
                           V,
                           dtype=float,
                           slab=(params.decomposition == 'slab'),
                           collapse_fourier=collapse_fourier,
                           **kw0)
    VT = VectorTensorProductSpace(T)

    # Different bases for nonlinear term, either 2/3-rule or 3/2-rule
    kw = {
        'padding_factor': 1.5 if params.dealias == '3/2-rule' else 1,
        'dealias_direct': params.dealias == '2/3-rule'
    }

    Vp = [
        Basis(params.N[i], 'F', domain=(0, params.L[i]), dtype=dtype(i), **kw)
        for i in range(dim)
    ]

    Tp = TensorProductSpace(comm,
                            Vp,
                            dtype=float,
                            slab=(params.decomposition == 'slab'),
                            collapse_fourier=collapse_fourier,
                            **kw0)
    VTp = VectorTensorProductSpace(Tp)

    # Mesh variables
    X = T.local_mesh(True)
    K = T.local_wavenumbers(scaled=True)
    for i in range(dim):
        X[i] = X[i].astype(float)
        K[i] = K[i].astype(float)
    K2 = np.zeros(T.local_shape(True), dtype=float)
    for i in range(dim):
        K2 += K[i] * K[i]

    # Set Nyquist frequency to zero on K that is, from now on, used for odd derivatives
    Kx = T.local_wavenumbers(scaled=True, eliminate_highest_freq=True)
    for i in range(dim):
        Kx[i] = Kx[i].astype(float)

    K_over_K2 = np.zeros(VT.local_shape(), dtype=float)
    for i in range(dim):
        K_over_K2[i] = K[i] / np.where(K2 == 0, 1, K2)

    # Velocity and pressure
    U = Array(VT)
    U_hat = Function(VT)
    P = Array(T)
    P_hat = Function(T)
    u_dealias = Array(VTp)

    # Primary variable
    u = U_hat

    # RHS array
    dU = Function(VT)
    curl = Array(VT)
    Source = Function(VT)  # Possible source term initialized to zero
    work = work_arrays()

    hdf5file = NSFile(config.params.solver,
                      checkpoint={
                          'space': VT,
                          'data': {
                              '0': {
                                  'U': [U_hat]
                              }
                          }
                      },
                      results={
                          'space': VT,
                          'data': {
                              'U': [U],
                              'P': [P]
                          }
                      })

    return config.AttributeDict(locals())
Example #2
0
def get_context():
    float, complex, mpitype = datatypes(params.precision)
    collapse_fourier = False if params.dealias == '3/2-rule' else True
    dim = len(params.N)
    dtype = lambda d: float if d == dim - 1 else complex
    V = [
        Basis(params.N[i], 'F', domain=(0, params.L[i]), dtype=dtype(i))
        for i in range(dim)
    ]

    kw0 = {
        'threads': params.threads,
        'planner_effort': params.planner_effort['fft']
    }
    T = TensorProductSpace(comm,
                           V,
                           dtype=float,
                           slab=(params.decomposition == 'slab'),
                           collapse_fourier=collapse_fourier,
                           **kw0)
    VT = VectorTensorProductSpace(T)
    VM = MixedTensorProductSpace([T] * 2 * dim)

    kw = {
        'padding_factor': 1.5 if params.dealias == '3/2-rule' else 1,
        'dealias_direct': params.dealias == '2/3-rule'
    }

    Vp = [
        Basis(params.N[i], 'F', domain=(0, params.L[i]), dtype=dtype(i), **kw)
        for i in range(dim)
    ]

    Tp = TensorProductSpace(comm,
                            Vp,
                            dtype=float,
                            slab=(params.decomposition == 'slab'),
                            collapse_fourier=collapse_fourier,
                            **kw0)
    VTp = VectorTensorProductSpace(Tp)
    VMp = MixedTensorProductSpace([Tp] * 2 * dim)

    # Mesh variables
    X = T.local_mesh(True)
    K = T.local_wavenumbers(scaled=True)
    for i in range(dim):
        X[i] = X[i].astype(float)
        K[i] = K[i].astype(float)
    K2 = np.zeros(T.local_shape(True), dtype=float)
    for i in range(dim):
        K2 += K[i] * K[i]

    # Set Nyquist frequency to zero on K that is, from now on, used for odd derivatives
    Kx = T.local_wavenumbers(scaled=True, eliminate_highest_freq=True)
    for i in range(dim):
        Kx[i] = Kx[i].astype(float)

    K_over_K2 = np.zeros(VT.local_shape(), dtype=float)
    for i in range(dim):
        K_over_K2[i] = K[i] / np.where(K2 == 0, 1, K2)

    UB = Array(VM)
    P = Array(T)
    curl = Array(VT)
    UB_hat = Function(VM)
    P_hat = Function(T)
    dU = Function(VM)
    Source = Array(VM)
    ub_dealias = Array(VMp)
    ZZ_hat = np.zeros((3, 3) + Tp.local_shape(True),
                      dtype=complex)  # Work array

    # Create views into large data structures
    U = UB[:3]
    U_hat = UB_hat[:3]
    B = UB[3:]
    B_hat = UB_hat[3:]

    # Primary variable
    u = UB_hat

    hdf5file = MHDFile(config.params.solver,
                       checkpoint={
                           'space': VM,
                           'data': {
                               '0': {
                                   'UB': [UB_hat]
                               }
                           }
                       },
                       results={
                           'space': VM,
                           'data': {
                               'UB': [UB]
                           }
                       })

    return config.AttributeDict(locals())