flowtube.kinetics

Kinetics calculations for flow tube experiments.

Functions

correction_factor(N_eff_Shw, Kn, gamma)	Calculate correction factor for uptake coefficient - eq.
cylinder_loss(obj, diameter, N_eff_Shw, Kn, ...)	Calculate penetration (unitless) - eq.
diffusion_limited_rate_constant(obj, ...)	Calculate diffusion limited rate constant (s-1) - eq.
diffusion_limited_uptake_coefficient(obj, ...)	Calculate diffusion limited effective uptake coefficient - eq.
fit_first_order_kinetics(obj, ...)	Fits the observed loss to a first order kinetic model to extract the uptake coefficient.
gamma_from_k(obj, k, diameter)	Calculate effective uptake coefficient from rate constant.
observed_loss_rate(obj, diameter, gamma_eff)	Calculate observed loss rate (s-1) - eq.

flowtube.kinetics.diffusion_limited_rate_constant(obj, N_eff_Shw, diameter)

Calculate diffusion limited rate constant (s-1) - eq. 10 from Knopf et al., 2015.

Parameters:

• obj (full_attrs) – Object with full attributes (P in Pa, T in K, reactant_diffusion_rate in cm2 s-1, carrier_dynamic_viscosity in kg m-1 s-1, carrier_density in kg m-3).

• N_eff_Shw (float) – Effective Sherwood number.

• diameter (float) – Diameter of the cylinder (cm).

Returns:

Diffusion limited rate constant (s-1).

Return type:

float

flowtube.kinetics.diffusion_limited_uptake_coefficient(obj, diameter, k_diff)

Calculate diffusion limited effective uptake coefficient - eq. 19 from Knopf et al., 2015.

Parameters:

• obj (full_attrs) – Object with full attributes (P in Pa, T in K, reactant_diffusion_rate in cm2 s-1, carrier_dynamic_viscosity in kg m-1 s-1, carrier_density in kg m-3).

• diameter (float) – Diameter of the cylinder (cm).

• k_diff (float) – Diffusion limited rate constant (s-1).

Returns:

Diffusion limited effective uptake coefficient (cm s-1).

Return type:

float

flowtube.kinetics.correction_factor(N_eff_Shw, Kn, gamma)

Calculate correction factor for uptake coefficient - eq. 20 from Knopf et al., 2015.

Parameters:

• N_eff_Shw (float) – Effective Sherwood number (unitless).

• Kn (float) – Knudsen number (unitless).

• hypothetical_gamma (float) – Hypothetical uptake coefficient (unitless).

• gamma (ndarray[tuple[Any, ...], dtype[float64]] | float)

Returns:

Correction factor (unitless).

Return type:

float

flowtube.kinetics.observed_loss_rate(obj, diameter, gamma_eff)

Calculate observed loss rate (s-1) - eq. 19 from Knopf et al., 2015.

Parameters:

• obj (full_attrs) – Object with full attributes (P in Pa, T in K, reactant_diffusion_rate in cm2 s-1, carrier_dynamic_viscosity in kg m-1 s-1, carrier_density in kg m-3).

• diameter (float) – Diameter of the cylinder (cm).

• gamma_eff (float) – Effective uptake coefficient (unitless).

Returns:

Observed loss rate (s-1).

Return type:

float

flowtube.kinetics.cylinder_loss(obj, diameter, N_eff_Shw, Kn, gamma, time)

Calculate penetration (unitless) - eq. 21 from Knopf et al., 2015.

Parameters:

• obj (full_attrs) – Object with full attributes (P in Pa, T in K, reactant_diffusion_rate in cm2 s-1, carrier_dynamic_viscosity in kg m-1 s-1, carrier_density in kg m-3).

• time (float) – Residence time in cylinder (s).

• diameter (float)

• N_eff_Shw (float)

• Kn (float)

• gamma (ndarray[tuple[Any, ...], dtype[float64]] | float)

Returns:

Penetration - fraction of initial reactant after passing

through cylinder (unitless).

Return type:

float

flowtube.kinetics.gamma_from_k(obj, k, diameter)

Calculate effective uptake coefficient from rate constant.

Parameters:

• obj (full_attrs) – Object with full attributes (P in Pa, T in K, reactant_diffusion_rate in cm2 s-1, carrier_dynamic_viscosity in kg m-1 s-1, carrier_density in kg m-3).

• k (float) – Rate constant (s-1).

• diameter (float) – Diameter of the cylinder (cm).

Returns:

Effective uptake coefficient (unitless).

Return type:

float

flowtube.kinetics.fit_first_order_kinetics(obj, concentrations, exposure, exposure_units)

Fits the observed loss to a first order kinetic model to extract the uptake coefficient.

Parameters:

• obj (full_attrs) – Object with full attributes (P in Pa, T in K, reactant_diffusion_rate in cm2 s-1, carrier_dynamic_viscosity in kg m-1 s-1, carrier_density in kg m-3).

• concentrations (NDArray[np.float64]) – Array of observed concentrations (unitless).

• exposure (NDArray[np.float64]) – Array of exposures (s or cm).

• exposure_units (str) – Units of exposure (“s”, “sec”, “second”, “seconds”, “cm”, “centimeter”, “centimeters”).

Returns:

Tuple containing the

slope, intercept, r-value, p-value, and standard error of the regression.

Return type:

tuple[float, float, float, float, float]