Utility modules

constants

exceptions

exception src.utils.exceptions.SupplyDataMissingError

Bases: Exception

A custom exception raised when supply data is missing before return calculation.

functions

src.utils.functions.calculate_average_flow_velocity(v_flow_m_per_s)

Calculates the average velocity of the fluid flow in the pipeline in [m/s].

Parameters:

v_flow_m_per_s (list) – list of fluid values in each pipe section in [m/s]

Return v_avg_m_per_s:

average flow velocity in the pipeline in [m/s]

Return type:

float

src.utils.functions.calculate_flow_velocity(den_fluid, mdot_flow, d_pipe_inner)

Calculates the velocity inside an individual segment of the pipeline (based on mass flow) in [m/s].

Parameters:

• den_fluid (float) – density of the fluid in [kg/m3]

• mdot_flow (float) – fluid mass flow in [kg/s]

• d_pipe_inner (float) – the internal diameter of the pipeline section in [m]

Return v_flow:

velocity of flow [m/s]

Return type:

float

src.utils.functions.calculate_fluid_density(p, t, fluid='Water')

Defines the fluid density in [kg/m3].

Parameters:

• p (float) – avrega pressure in the pipeline in [Pa]

• t (float) – temperature in [K]

• fluid (str) – fluid type

Return den:

density in [kg/m3]

Return type:

float

src.utils.functions.calculate_fluid_specific_heat(p, t, fluid='Water')

Defines the fluid specific heat in [Ws/kgK].

Parameters:

• p (float) – avrega pressure in the pipeline in [Pa]

• t (float) – temperature in [K]

• fluid (str) – fluid type

Return cp:

specific heat coefficient in [Ws/kgK]

Return type:

float

src.utils.functions.calculate_heat_flow(t_high, t_low, mdot, cp)

Calculates the flow of thermal energy inside the pipeline [W].

Parameters:

• t_high (float) – higher temperature in [°C]

• t_low (float) – lower temperature in [°C]

• mdot (float) – mass flow in [kg/s]

• cp (float) – specific heating capacity coefficient in [Ws/kgK]

Return qdot:

heat flow in [W]

Return type:

float

src.utils.functions.calculate_heat_flow_loss(r_tot, t_outer, t_inner)

Calculates the flow of thermal energy loss in [W].

Parameters:

• r_tot (float) – total thermal resistance of a pipe section in [K/W]

• t_outer (float) – ambient temperature in [K]

• t_inner (float) – temperature of the fluid inside the pipeline in [K]

Return qdot_loss:

heat loss flow in [W]

Return type:

float

src.utils.functions.calculate_insulation_external_diameter(d_pipe_external, th_insulation)

Calculates the external diameter of the insulation of a chosen pipe section.

Parameters:

• d_pipe_external (float) – external diameter of the chosen pipe section in [m]

• th_insulation (float) – insulation thickness of the chosen section in [m]

Return d_insulation_external:

external diameter of the chosen section in [m]

Return type:

float

src.utils.functions.calculate_insulation_thickness(location, d_pipe_nominal, th_insulation_dict)

Calculates the thickness of pipe section insulation based on its location in [m].

Parameters:

• location (str) – ‘channel’, ‘surface’, or ‘soil’

• d_pipe_external – External pipe diameter at the given index in [m]

• th_insulation_dict (dict) – Dictionary with thickness data

Return th_insulation:

Insulation thickness in [m]

Return type:

float

src.utils.functions.calculate_output_temperature(t_in, t_amb, mdot, cp, r_tot, tolerance=0.001)

Iteratively compute the outlet temperature accounting for energy loss and return the final heat loss.

Parameters:

• t_in (float) – Inlet temperature in [°C]

• t_amb (float) – Ambient temperature in [°C]

• mdot (float) – Mass flow rate in [kg/s]

• cp (float) – Specific heat coefficient in [Ws/kgK]

• r_tot (float) – Total thermal resistance in [K/W]

• tolerance (float) – Convergence tolerance (default 0.01 = 1%)

Return type:

Tuple[float, float]

Returns:

t_out_c: Final outlet temperature in [°C] qdot_loss: Final heat flow loss in [W]

src.utils.functions.calculate_pipe_internal_diameter(d_pipe_external, th_pipe)

Calculates the internal diameter of a chosen pipe section.

Parameters:

• d_pipe_external (float) – external diameter of the chosen pipe section in [m]

• th_pipe (float) – pipe wall thickness of the chosen section in [m]

Return d_pipe_internal:

internal diameter of the chosen pipe section in [m]

Return type:

float

src.utils.functions.calculate_r_conduction(d_outer_m, d_inner_m, l_m, k_w_per_mk)

Calculates the conduction resistance of a cylindrical element.

Parameters:

• d_outer – pipe external diameter in [m]

• d_inner – pipe internal diameter in [m]

• l_m (float) – pipe (section) lenght in [m]

• k_w_per_mk (float) – the material conductivity coefficient in [W/mK]

Return r_cond:

conduction resistance in [K/W]

Return type:

float

src.utils.functions.calculate_r_convection(d_m, l_m, h_w_per_m2k)

Calculates the convection resistance of a cylindrical element.

Parameters:

• d_m (float) – diameter of the surface for the convection in [m]

• l_m (float) – pipe (section) lenght in [m]

• h_w_per_m2k (float) – the material convection coefficient in [W/m2K]

Return r_conv:

convection resistance in [K/W]

Return type:

float

src.utils.functions.calculate_r_total(d_pipe_inner_m, l_m, h_mat1_w_per_m2k, d_pipe_outer_m, k_mat1_w_per_mk, d_ins_outer_m, k_mat2_w_per_mk, h_loc_w_per_m2k)

Calculates the total thermal resistance of a cylindrical element —> fluid-pipe-insulation-air.

Parameters:

• d_pipe_inner_m (float) – diameter of the surface for the convection inside the pipe section in [m]

• l_m (float) – pipe section lenght in [m]

• h_mat1_w_per_m2k (float) – the pipe heat transfer coefficient in [W/m2K]

• d_pipe_outer_m (float) – external diameter of the pipe section in [m]

• k_mat1_w_per_mk (float) – the pipe conductivity coefficient in [W/mK]

• d_ins_outer_m (float) – external diameter of the insulation in [m]

• k_mat2_w_per_mk (float) – the insulation conductivity coefficient in [W/mK]

• h_loc_w_per_m2k (float) – heat transfer coefficient based on the location of the pipe section (surface, channel, soil) in [W/m2K]

Return r_tot:

total thermal resistance in [K/W]

Return type:

float

src.utils.functions.select_ambient_temperature(location)

Selects the external temperature based on the location of the pipeline section.

Parameters:

location (str) – position of pipeline section

Return t_amb:

temperature of the sorounding ambient in [°C]

Return type:

float

src.utils.functions.select_heat_transfer_coeff(location)

Selects the heat transfer coefficient based on the location of the pipeline section.

Parameters:

location (str) – position of pipeline section

Return h_conv:

value of the heat transfer coefficient read from data table

Return type:

float

validation

src.utils.validation.validate_damage(mode, percent)

Validates and processes the insulation damage percentage input.

Parameters:

• mode (str) – The mode of damage input (‘average’ or ‘element’).

• percent (Union[float, int, List[Union[float, int]]]) – The value(s) representing insulation damage percentage.

Return type:

Tuple[Optional[float], Optional[List[float]]]

Returns:

average_percent element_percent_list

Raises:

TypeError, ValueError –