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Class: MassFlowRate

The MassFlowRate class is a subclass of Variable designed to represent the mass of a substance passing per unit of time. It ensures accurate calculations by storing all values internally in its base SI unit, kilograms per second (kg/s).

Supported Units

The following units are supported for initialization and conversion.

Unit str Conversion Factor to Kilograms per Second (kg/s)
kilograms per second kg/s 1
kilograms per hour kg/h 1/3600
grams per second g/s 0.001
grams per minute g/min 0.001/60
grams per hour g/h 0.001/3600
pounds per second lb/s 0.453592
pounds per minute lb/min 0.453592/60
pounds per hour lb/h 0.453592/3600
kilograms per day kg/day 1/86400
tons per day t/day 0.0115740741

Class Reference

class MassFlowRate(value, units='kg/s')

A class for handling mass flow rate measurements with automatic unit conversion.

Parameters:

  • value : float or int
    The numeric value of the mass flow rate. Must be a non-negative number.
  • units : str, default='kg/s'
    The unit of the provided value. Must be one of the supported units.

Raises:

  • ValueError : If value is negative.
  • TypeError : If units is not a valid unit.

Examples: 

# Create a MassFlowRate object of 100 kg/h  
>>> mfr1 = MassFlowRate(100, "kg/h")

# Create a MassFlowRate object of 0.5 lb/s  
>>> mfr2 = MassFlowRate(0.5, "lb/s")

Properties

Property Type Description
.value float The numeric value of the mass flow rate, always in kilograms per second (kg/s). This is the internal representation used for all calculations.
.original_value float The numeric value as provided during initialization.
.original_unit str The unit as provided during initialization.

Methods

to(target_unit)

Returns a new MassFlowRate object converted to the target_unit. The original object remains unchanged.

Parameters:

  • target_unit : str
    The unit to convert to. Must be one of the supported units.

Returns:

  • MassFlowRate
    A new MassFlowRate object with the same value, represented in the target unit.

Raises:

  • TypeError : If target_unit is not a valid unit.

Examples: 

# Initialize a mass flow rate of 100 kg/h  
>>> flow_kg_h = MassFlowRate(100, "kg/h")

# Convert to kg/s  
>>> flow_kg_s = flow_kg_h.to("kg/s")

>>> print(flow_kg_s)  
0.027778 kg/s

String Representation

  • __str__(self) Returns a human-readable string representation of the mass flow rate, rounded to six decimal places, using its original value and unit.
  • __repr__(self)
    Returns a string representation suitable for developers and debugging.