citysim_components_hydraulics

Functions to compute pressure and its derivatives for citysim components

compute_dp_pump_cs(mdot: float | ndarray, rpm: float | ndarray = 2500.0, rpm_max: float | ndarray = 5000.0, a0: float | ndarray = 1200000.0, a1: float | ndarray = 0.0, a2: float | ndarray = 0.0) → float | ndarray[source]

Computes the differential pressure in pumps using the following equation:

\[\Delta p = -\left( a_0 \frac{n^2}{n_0^2} + a_1 \frac{n}{n_0} + a_2 \ \right), \; \text{if } \dot m \geq 0\]
\[\Delta p = - a_0 \frac{n^2}{n_0^2}, \; \text{otherwise}\]
Parameters:

  • mdot (float | ndarray) – Mass flow (kg/s).

  • rpm (float | ndarray, optional) – Speed in revolutions per minute \(n\): (1/min). The default is 2500.0.

  • rpm_max (float | ndarray, optional) – Maximum speed in revolutions per minute \(n_0\): (1/min). The default is 5000.0.

  • a0 (float | ndarray, optional) – First pump parameter. The default is 1200000.0.

  • a1 (float | ndarray, optional) – Second pump parameter. The default is 0.0.

  • a2 (float | ndarray, optional) – Third pump parameter. The default is 0.0.

Returns:

Pressure difference (Pa).

Return type:

float | ndarray

compute_dp_pump_cs_der(mdot: float | ndarray[float], rpm: float | ndarray = 2500.0, rpm_max: float | ndarray = 5000.0, a0: float | ndarray = 1200000.0, a1: float | ndarray = 0.0, a2: float | ndarray = 0.0) → float | ndarray[source]

Returns the derivative of compute_dp_pump_cs().

Parameters:

  • mdot (float | ndarray) – Mass flow (kg/s).

  • rpm (float | ndarray, optional) – Speed in revolutions per minute \(n\): (1/min). The default is 2500.0.

  • rpm_max (float | ndarray, optional) – Maximum speed in revolutions per minute \(n_0\): (1/min). The default is 5000.0.

  • a0 (float | ndarray, optional) – First pump parameter. The default is 1200000.0.

  • a1 (float | ndarray, optional) – Second pump parameter. The default is 0.0.

  • a2 (float | ndarray, optional) – Third pump parameter. The default is 0.0.

Returns:

Value of the derivative.

Return type:

float | ndarray

compute_dp_valve_cs(mdot: float | ndarray, kv: float | ndarray = 0.0, rho_fluid: float | ndarray = 990.0) → float | ndarray[source]

Computes the differential pressure in valves according to the formula:

\[\Delta p = \frac{1.296 \cdot 10^9}{\rho K_v^2} \| \dot m \| \dot m\]
Parameters:

  • mdot (float | ndarray) – Mass flow in kg/s.

  • kv (float | ndarray, optional) – Flow coefficient \(K_v\). The default is 0.0.

  • rho_fluid (float | ndarray, optional) – Density (kg/m^3) of the fluid. The default is 990.0.

Returns:

Pressure difference (Pa).

Return type:

float | ndarray

compute_dp_valve_cs_der(mdot: float | ndarray, kv: float | ndarray = 0.0, rho_fluid: float | ndarray = 990.0) → float | ndarray[source]

Returns the derivative of compute_dp_valve_cs() .

Parameters:

  • mdot (float | ndarray) – Mass flow in kg/s.

  • kv (float | ndarray, optional) – Flow coefficient \(K_v\). The default is 0.0.

  • rho_fluid (float | ndarray, optional) – Density (kg/m^3) of the fluid. The default is 990.0.

Returns:

Value of the derivative.

Return type:

float | ndarray