Discharge

Functions to evaluate fuel cell discharge losses and voltage requirements. More...

Functions
def	SUAVE.Methods.Power.Fuel_Cell.Discharge.find_power_diff_larminie.find_power_diff_larminie (current_density, fuel_cell, power_desired)
def	SUAVE.Methods.Power.Fuel_Cell.Discharge.find_power_larminie.find_power_larminie (current_density, fuel_cell, sign=1.0)
def	SUAVE.Methods.Power.Fuel_Cell.Discharge.find_voltage_larminie.find_voltage_larminie (fuel_cell, current_density)
def	SUAVE.Methods.Power.Fuel_Cell.Discharge.larminie.larminie (fuel_cell, conditions, numerics)
def	SUAVE.Methods.Power.Fuel_Cell.Discharge.setup_larminie.setup_larminie (fuel_cell)
	default values representative of a hydrogen fuel cell More...
def	SUAVE.Methods.Power.Fuel_Cell.Discharge.zero_fidelity.zero_fidelity (fuel_cell, conditions, numerics)
	zero_fidelity.py More...

Detailed Description

Functions to evaluate fuel cell discharge losses and voltage requirements.

Function Documentation

find_power_diff_larminie()

def SUAVE.Methods.Power.Fuel_Cell.Discharge.find_power_diff_larminie.find_power_diff_larminie	(		current_density,
			fuel_cell,
			power_desired
	)

function that determines the power difference between the actual power
and a desired input power, based on an input current density

Assumptions:
None

Inputs:
current_density                [Amps/m**2]
power_desired                  [Watts]
fuel_cell
  

Outputs
(power_desired-power_out)**2   [Watts**2]

find_power_larminie()

def SUAVE.Methods.Power.Fuel_Cell.Discharge.find_power_larminie.find_power_larminie	(		current_density,
			fuel_cell,
			sign = 1.0
	)

Function that determines the power output per cell, based on in 
input current density

Assumptions:
None(calls other functions)

Inputs:
current_density      [Amps/m**2]
fuel cell.
    interface area   [m**2]
    
Outputs:
power_out            [W]

find_voltage_larminie()

def SUAVE.Methods.Power.Fuel_Cell.Discharge.find_voltage_larminie.find_voltage_larminie	(		fuel_cell,
			current_density
	)

function that determines the fuel cell voltage based on an input
current density and some semi-empirical values to describe the voltage
drop off with current

Assumptions:
voltage curve is a function of current density of the form
v = Eoc-r*i1-A1*np.log(i1)-m*np.exp(n*i1)

Inputs:
current_density           [A/m**2]
fuel_cell.
    r                     [Ohms*m**2]
    A1                    [V]
    m                     [V]
    n                     [m**2/A]
    Eoc                   [V]
   
Outputs:
    V                     [V]

larminie()

def SUAVE.Methods.Power.Fuel_Cell.Discharge.larminie.larminie	(		fuel_cell,
			conditions,
			numerics
	)

function that determines the mass flow rate based on a required power input

Assumptions:
None (calls other functions)

Inputs:
fuel_cell.
    inputs.
        power_in       [W]
    ideal_voltage      [V] 

Outputs:
    mdot               [kg/s]

setup_larminie()

def SUAVE.Methods.Power.Fuel_Cell.Discharge.setup_larminie.setup_larminie

(

fuel_cell

)

default values representative of a hydrogen fuel cell

sets up additional values of fuel cell to run method from Larminie and 
Dicks (Fuel Cell Systems Explained)

Inputs:
    fuel cell
 
Outputs:
    fuel_cell.
        number_of_cells
        interface_area       [m**2]
        r                    [ohms*m**2]
        Eoc                  [V]
        A1                   [V]
        m                    [V]
        n                    [m**2/A]
        ideal_voltage        [V]
        cell_density         [kg/m^3]
        porousity_coeffient  

zero_fidelity()

def SUAVE.Methods.Power.Fuel_Cell.Discharge.zero_fidelity.zero_fidelity	(		fuel_cell,
			conditions,
			numerics
	)

zero_fidelity.py

Created : Apr 2015, M. Vegh Modified: Sep 2015, M. Vegh Feb 2016, E. Botero

Assumptions:
constant efficiency

Inputs:
    fuel_cell.
        inputs.
            power_in              [W]
        propellant.
            specific_energy       [J/kg]
        efficiency    

Outputs:
    mdot                          [kg/s]