The util submodule

Hydraulic utility functions and conversion helpers.

This module contains standalone helpers used across fluidsolve for common engineering calculations and unit-safe conversions. It is not centered on a single class; instead, it provides reusable computational primitives.

Main responsibilities:

  • pressure/head/velocity/flow conversion utilities,

  • helper formulas for hydraulic loss calculations,

  • convenience wrappers around selected fluids correlations,

  • small numerical helper routines shared by components and tools.

Design intent:

  • keep frequently reused equations in one importable location,

  • avoid duplicating conversion logic in component classes,

  • preserve unit consistency by using the shared quantity system.

Typical usage:

H = PtoH(2.0 * u.bar, 998 * u.kg / u.m**3)
P = Htop(10 * u.m, 998 * u.kg / u.m**3)
out = calcOrifice(Q=2.5 * u.m**3 / u.h, d=50 * u.mm, orifice=20 * u.mm)

These helpers are intended as low-level building blocks used by higher-level objects such as components, paths, and network solvers.

fluidsolve.util.calcOrifice(**kwargs: Any) → Any[source]
This function calculates either the flow rate, the upstream pressure,

the second pressure or the orifice diameter for an orifice.

For details see https://fluids.readthedocs.io/fluids.flow_meter.html

Parameters:

  • medium (Medium, optional) – The medium to be used. Defaults to water

  • Q (int | float | Quantity, optional) – The flow rate. If not provided, this is the variable to be calculated.

  • d (int | float | Quantity, optional) – The pipe diameter (in mm) If not provided, this is the variable to be calculated.

  • orifice (int | float | Quantity | str, optional) – The orifice diameter size (in mm). If not provided, this is the variable to be calculated.

  • Pin (int | float | Quantity, optional) – The pressure before the orifice (in bar). If not provided, this is the variable to be calculated.

  • Pout (int | float | Quantity, optional) – The pressure after the orifice (in bar). If not provided, this is the variable to be calculated.

  • meter (str, optional) – Fluids orifice meter type.

  • orifice – Orifice diameter (in mm) or, when used as the orifice_taps slot, the tap position string (e.g. 'corner').

fluidsolve.util.calcOrifice2(circuit: ~typing.Any, Q: ~typing.Any, d: ~typing.Any, Puit: ~typing.Any = <Quantity(1, 'bar')>, meter_type: ~typing.Any = 'ISO 5167 orifice', orifice_taps: ~typing.Any = 'corner') → Any[source]

Solve for the orifice beta ratio that matches a given flow rate and circuit head.

Parameters:

  • circuit – Circuit object providing fluid properties and head curve.

  • Q (Quantity) – Flow rate.

  • d (Quantity) – Pipe diameter.

  • Puit (Quantity, optional) – Downstream pressure.

  • meter_type (str, optional) – Fluids orifice meter type.

  • orifice_taps (str, optional) – Fluids orifice taps.

Returns:

Orifice diameter.

Return type:

Quantity

fluidsolve.util.KtoFd(K: int | float, L: int | float | Quantity, D: int | float | Quantity) → float[source]

Calculate friction factor Fd from loss coefficient K

Parameters:

  • K (int | float) – loss coefficient

  • L (int | float | Quantity) – Length (default in m)

  • D (int | float | Quantity) – (Hydraulic) Diameter (default in mm)

Returns:

friction factor

Return type:

float

fluidsolve.util.FdtoK(Fd: int | float, L: int | float | Quantity, D: int | float | Quantity) → float[source]

Calculate loss coefficient K from friction factor Fd

Parameters:

  • Fd (int | float) – friction factor

  • L (int | float | Quantity) – Length (default in m)

  • D (int | float | Quantity) – (Hydraulic) Diameter (default in mm)

Returns:

loss coefficient

Return type:

float

fluidsolve.util.KvtoK(Kv: int | float | Quantity, D: int | float | Quantity) → float[source]

Calculate loss coefficient K from valve flow coefficient Kv

Parameters:

  • Kv (int | float| Quantity) – valve flow coefficient (default in m3/h)

  • D (int | float | Quantity) – (Hydraulic) Diameter (default in mm)

Returns:

loss coefficient

Return type:

float

fluidsolve.util.KtoKv(K: int | float, D: int | float | Quantity) → Quantity[source]

Calculate valve flow coefficient Kv from loss coefficient K

Parameters:

  • K (int | float) – loss coefficient

  • D (int | float | Quantity) – (Hydraulic) Diameter (default in mm)

Returns:

valve flow coefficient (in m3/h)

Return type:

Quantity

fluidsolve.util.CvtoK(Cv: int | float | Quantity, D: int | float | Quantity) → float[source]

Calculate loss coefficient K from imperial valve flow coefficient Cv

Parameters:

  • Cv (int | float| Quantity) – imperial valve flow coefficient (default in gallons/min)

  • D (int | float | Quantity) – (Hydraulic) Diameter (default in mm)

Returns:

loss coefficient

Return type:

float

fluidsolve.util.KtoCv(K: int | float, D: int | float | Quantity) → Quantity[source]

Calculate imperial valve flow coefficient Kv from loss coefficient K

Parameters:

  • K (int | float) – loss coefficient

  • D (int | float | Quantity) – (Hydraulic) Diameter (default in mm)

Returns:

valve flow coefficient (in gallons/min)

Return type:

Quantity

fluidsolve.util.CvtoKv(Cv: int | float | Quantity) → float[source]

Calculate valve flow coefficient Kv from imperial valve flow coefficient Cv

Parameters:

Cv (int | float| Quantity) – imperial valve flow coefficient (default in gallons/min)

Returns:

valve flow coefficient (in m3/h)

Return type:

Quantity

fluidsolve.util.KvtoCv(Kv: int | float | Quantity) → float[source]

Calculate imperial valve flow coefficient Cv from valve flow coefficient Kv

Parameters:

Kv (int | float | Quantity) – valve flow coefficient (default in m3/h)

Returns:

imperial valve flow coefficient (in gallons/min)

Return type:

Quantity

fluidsolve.util.KtoH(K: int | float, v: int | float | Quantity) → Quantity[source]

Calculate hydraulic height from loss coefficient K

Parameters:

  • K (int | float) – loss coefficient

  • v (int | float | Quantity) – fluid velocity (default in m/s)

Returns:

hydraulic heigh (in m)

Return type:

Quantity

fluidsolve.util.Ktop(K: int | float, v: int | float | Quantity, rho: int | float | Quantity) → Quantity[source]

Calculate hydraulic pressure from loss coefficient K

Parameters:

  • K (int | float) – loss coefficient

  • v (int | float | Quantity) – fluid velocity (default in m/s)

  • rho (int | float | Quantity) – density (default in kg/m3)

Returns:

hydraulic pressure (in bar)

Return type:

Quantity

fluidsolve.util.Htop(H: int | float | Quantity, rho: int | float | Quantity) → Quantity[source]

Calculate hydraulic pressure from hydraulic height

Parameters:

  • H (int | float | Quantity) – hydraulic height (default in m)

  • rho (int | float | Quantity) – density (default in kg/m3)

Returns:

hydraulic pressure (in bar)

Return type:

Quantity

fluidsolve.util.ptoH(p: int | float | Quantity, rho: int | float | Quantity) → Quantity[source]

Calculate hydraulic height from hydraulic pressure

Parameters:

  • p (int | float | Quantity) – hydraulic pressure (default in bar)

  • rho (int | float | Quantity) – density (default in kg/m3)

Returns:

hydraulic height (in m)

Return type:

Quantity

fluidsolve.util.Qtov(Q: int | float | Quantity, D: int | float | Quantity) → Quantity[source]

Calculate velocity (in m/s) from flow rate depending on diameter.

Parameters:

  • Q (int | float | Quantity) – Flow to convert (default in m3/h).

  • D (int | float | Quantity) – diameter (default in mm).

Returns:

Corresponding velocity (in m/s).

Return type:

Quantity

fluidsolve.util.vtoQ(v: int | float | Quantity, D: int | float | Quantity) → Quantity[source]

Calculate flow rate (in m/s) from velocity depending on diameter.

Parameters:

  • v (int | float | Quantity) – Velocity to convert (default in m/s).

  • D (int | float | Quantity) – diameter (default in mm).

Returns:

Corresponding flow rate (in m3/h).

Return type:

Quantity

fluidsolve.util.calcCurve(xb: Any, xe: Any, xn: Any, yfun: Any, yb: Any, ye: Any) → Any[source]

Sample a function over a range and return clipped x/y arrays.

Parameters:

  • xb (float) – Start of x range.

  • xe (float) – End of x range.

  • xn (int) – Number of sample points.

  • yfun (Callable) – Function mapping x values to y values.

  • yb (float) – Lower y clip bound.

  • ye (float) – Upper y clip bound.

Returns:

Clipped x and y arrays.

Return type:

tuple[np.ndarray, np.ndarray]