divertor

st_div(stellarator, f_output)

Routine to call the stellarator divertor model

This routine calls the divertor model for a stellarator

Parameters:

Name	Type	Description	Default
stellarator		An object containing stellarator configuration and output handle	required
f_output	bool		required

References

Stellarator Divertor Model for the Systems Code PROCESS, F. Warmer, 21/06/2013

Source code in process/models/stellarator/divertor.py

def st_div(stellarator, f_output: bool):
    """Routine to call the stellarator divertor model

    This routine calls the divertor model for a stellarator

    Parameters
    ----------
    stellarator :
        An object containing stellarator configuration and output handle
    f_output:

    References
    ----------
    Stellarator Divertor Model for the Systems Code PROCESS, F. Warmer, 21/06/2013
    """
    Theta = stellarator_variables.flpitch  # ~bmn [rad] field line pitch
    r = physics_variables.rmajor
    p_div = physics_variables.p_plasma_separatrix_mw
    alpha = divertor_variables.anginc
    xi_p = divertor_variables.xpertin
    T_scrape = divertor_variables.tdiv

    #  Scrape-off temperature in Joules

    e = T_scrape * constants.ELECTRON_CHARGE

    #  Sound speed of particles (m/s)

    c_s = np.sqrt(e / (physics_variables.m_fuel_amu * constants.UMASS))

    #  Island size (m)

    w_r = 4.0e0 * np.sqrt(
        stellarator_variables.bmn
        * r
        / (stellarator_variables.shear * stellarator_variables.n_res)
    )

    #  Perpendicular (to plate) distance from X-point to divertor plate (m)

    Delta = stellarator_variables.f_w * w_r

    #  Length 'along' plasma (m)

    l_p = 2 * np.pi * r * (stellarator_variables.m_res) / stellarator_variables.n_res

    #  Connection length from X-point to divertor plate (m)

    l_x_t = Delta / Theta

    #  Power decay length (m)

    l_q = np.sqrt(xi_p * (l_x_t / c_s))

    #  Channel broadening length (m)

    l_b = np.sqrt(xi_p * l_p / (c_s))

    #  Channel broadening factor

    f_x = 1.0e0 + (l_b / (l_p * Theta))

    #  Length of a single divertor plate (m)

    l_d = f_x * l_p * (Theta / alpha)

    #  Total length of divertor plates (m)

    l_t = 2.0e0 * stellarator_variables.n_res * l_d

    #  Wetted area (m2)

    a_eff = l_t * l_q

    #  Divertor plate width (m): assume total area is wetted area/stellarator_variables.fdivwet

    darea = a_eff / stellarator_variables.fdivwet
    l_w = darea / l_t

    #  Divertor heat load (MW/m2)

    q_div = stellarator_variables.f_asym * (p_div / a_eff)

    #  Transfer to global variables

    divertor_variables.pflux_div_heat_load_mw = q_div
    divertor_variables.a_div_surface_total = darea

    fwbs_variables.f_ster_div_single = darea / first_wall_variables.a_fw_total

    if f_output:
        output(stellarator, a_eff, l_d, l_w, f_x, l_q, w_r, Delta)

output(stellarator, a_eff, l_d, l_w, f_x, l_q, w_r, Delta)

Outputs a summary of divertor-related parameters and results to the stellartor object. stellarator: An object containing stellarator configuration and output handle.

The function writes various physical and geometric parameters related to the divertor, including power, angles, heat transport coefficients, resonance numbers, field perturbations, and other relevant quantities, to the output file associated with the stellarator object.

Parameters:

Name	Type	Description	Default
stellarator		An object containing stellarator configuration and output handle	required
a_eff		Effective divertor wetted area (m²).	required
l_d		Divertor plate length (m).	required
l_w		Divertor plate width (m).	required
f_x		Flux channel broadening factor.	required
l_q		Power decay width (m).	required
w_r		Island width (m).	required
Delta		Perpendicular distance from X-point to plate (m).	required

Source code in process/models/stellarator/divertor.py

def output(stellarator, a_eff, l_d, l_w, f_x, l_q, w_r, Delta):
    """Outputs a summary of divertor-related parameters and results to the stellartor object.
        stellarator: An object containing stellarator configuration and output handle.

    The function writes various physical and geometric parameters related to the divertor,
    including power, angles, heat transport coefficients, resonance numbers, field perturbations,
    and other relevant quantities, to the output file associated with the stellarator object.

    Parameters
    ----------
    stellarator :
        An object containing stellarator configuration and output handle
    a_eff :
        Effective divertor wetted area (m²).
    l_d :
        Divertor plate length (m).
    l_w :
        Divertor plate width (m).
    f_x :
        Flux channel broadening factor.
    l_q :
        Power decay width (m).
    w_r :
        Island width (m).
    Delta :
        Perpendicular distance from X-point to plate (m).

    """

    po.oheadr(stellarator.outfile, "Divertor")

    po.ovarre(
        stellarator.outfile,
        "Power to divertor (MW)",
        "(p_plasma_separatrix_mw.)",
        physics_variables.p_plasma_separatrix_mw,
    )
    po.ovarre(
        stellarator.outfile,
        "Angle of incidence (deg)",
        "(anginc)",
        divertor_variables.anginc * 180.0e0 / np.pi,
    )
    po.ovarre(
        stellarator.outfile,
        "Perp. heat transport coefficient (m2/s)",
        "(xpertin)",
        divertor_variables.xpertin,
    )
    po.ovarre(
        stellarator.outfile,
        "Divertor plasma temperature (eV)",
        "(tdiv)",
        divertor_variables.tdiv,
    )
    po.ovarre(
        stellarator.outfile,
        "Radiated power fraction in SOL",
        "(f_rad)",
        stellarator_variables.f_rad,
    )
    po.ovarre(
        stellarator.outfile,
        "Heat load peaking factor",
        "(f_asym)",
        stellarator_variables.f_asym,
    )
    po.ovarin(
        stellarator.outfile,
        "Poloidal resonance number",
        "(m_res)",
        stellarator_variables.m_res,
    )
    po.ovarin(
        stellarator.outfile,
        "Toroidal resonance number",
        "(n_res)",
        stellarator_variables.n_res,
    )
    po.ovarre(
        stellarator.outfile,
        "Relative radial field perturbation",
        "(bmn)",
        stellarator_variables.bmn,
    )
    po.ovarre(
        stellarator.outfile,
        "Field line pitch (rad)",
        "(flpitch)",
        stellarator_variables.flpitch,
    )
    po.ovarre(
        stellarator.outfile,
        "Island size fraction factor",
        "(f_w)",
        stellarator_variables.f_w,
    )
    po.ovarre(
        stellarator.outfile,
        "Magnetic stellarator_variables.shear (/m)",
        "(shear)",
        stellarator_variables.shear,
    )
    po.ovarre(stellarator.outfile, "Divertor wetted area (m2)", "(A_eff)", a_eff)
    po.ovarre(
        stellarator.outfile,
        "Wetted area fraction of total plate area",
        "(fdivwet)",
        stellarator_variables.fdivwet,
    )
    po.ovarre(stellarator.outfile, "Divertor plate length (m)", "(L_d)", l_d)
    po.ovarre(stellarator.outfile, "Divertor plate width (m)", "(L_w)", l_w)
    po.ovarre(stellarator.outfile, "Flux channel broadening factor", "(F_x)", f_x)
    po.ovarre(stellarator.outfile, "Power decay width (cm)", "(100*l_q)", 100.0e0 * l_q)
    po.ovarre(stellarator.outfile, "Island width (m)", "(w_r)", w_r)
    po.ovarre(
        stellarator.outfile,
        "Perp. distance from X-point to plate (m)",
        "(Delta)",
        Delta,
    )
    po.ovarre(
        stellarator.outfile,
        "Peak heat load (MW/m2)",
        "(pflux_div_heat_load_mw)",
        divertor_variables.pflux_div_heat_load_mw,
    )