Dynamic Influent

QSDsan: Quantitative Sustainable Design for sanitation and resource recovery systems

This module is developed by:

Joy Zhang <joycheung1994@gmail.com>

This module is under the University of Illinois/NCSA Open Source License. Please refer to https://github.com/QSD-Group/QSDsan/blob/main/LICENSE.txt for license details.

class qsdsan.sanunits._dynamic_influent.DynamicInfluent(ID='', ins: Sequence[AbstractStream] | None = None, outs: Sequence[AbstractStream] | None = (), data_file=None, by_mass=False, interpolator=None, derivative_approximator=None, thermo=None, init_with='WasteStream', isdynamic=True, load_data_kwargs={}, intpl_kwargs={}, **kwargs)

A fake SanUnit to generate a dynamic WasteStream at its outlet by interpolating time-series data.

Parameters:

  • ID (str, optional) – ID for the dynamic influent generator. The default is ‘’.

  • outs (WasteStream) – Dynamic influent.

  • data_file (str, optional) – The file path for the time-series data. Acceptable file extensions are .xlsx, .xls, .csv, .tsv. If none specified, will load the default time-series data of dry-weather influent with components from ASM1.

  • by_mass (bool, optional) –

    Whether time-series data indicate mass flowrates. If True, all columns assumed in kg/hr. If False, data are assumed to indicate concentrations [mg/L] and total volumetric flowrate [m3/d]. The default is False.

    Note

    When by_mass is set to True, the state array of the unit as well as the state array of its effluent by default indicate mass flow rates in g/d. This may not be consistent with downstream assumptions.

interpolatorstr|int|callable, optional

Interpolation method to use. It can be a string (e.g., ‘slinear’, ‘quadratic’, ‘cubic’) or an integer within [1,5] to specify the order of a spline interpolation. Other strings will be passed on to scipy.interpolate.interp1d as the ‘kind’ argument. It can also be a class in scipy.interpolate that takes time-series data as input upon initiation. Interpolant that is not at least first-order differentiable is not recommended (e.g., linear interpolation). The default is scipy.interpolate.CubicSpline.

derivative_approximatorcallable, optional

Function that returns derivative of the variable at given time. If none specified, will use the derivative() method of (if available) of the interpolant.

load_data_kwargsdict, optional

Keyword arguments for loading the data file with the qsdsan.utils.load_data() function. The default is {}.

intpl_kwargsdict, optional

Keyword arguments for initiating the interpolant. The default is {}.

See also

scipy.interpolate.CubicSpline

scipy.interpolate.InterpolatedUnivariateSpline

scipy.interpolate.interp1d

derivative(t)

Returns the estimated time derivatives at time t.

property derivative_approximator

[callable] The function to estimate time derivatives.

interpolant(t)

Returns the interpolated values at time t.

property interpolator

[callable] The interpolation method.

line: str = 'Dynamic influent'

class-attribute Name denoting the type of Unit class. Defaults to the class name of the first child class

run()

Run mass and energy balance. This method also runs specifications user defined specifications unless it is being run within a specification (to avoid infinite loops).

See also

_run, specifications, add_specification, add_bounded_numerical_specification