Imperial Gallons per Day (imp-gal/d) to Cubic Centimeters per second (cm³/s) conversion

What is the Imperial Gallon per Day?

The Imperial gallon per day (imp gal/d) is a unit of volumetric flow rate that expresses how many Imperial gallons of a fluid pass a point over the span of one day. It is used in the UK and Commonwealth countries for water supply, well yields, plumbing, and utility metering.

Definition

One Imperial gallon per day equals one Imperial gallon of volume divided by the 86,400 seconds in a day. Expressed in SI units of litres per second:

$$1\ \text{imp-gal/d} = 0.0000526168\ \text{l/s}$$

This follows directly from the exact definitions: an Imperial gallon = 4.54609 L exactly, and one day = 86,400 s, so $4.54609 \div 86400 = 5.26168 \times 10⁻⁵$ L/s.

Origin and History

The Imperial gallon was fixed by the British Weights and Measures Act of 1824, originally as the volume of 10 pounds of distilled water. It was later redefined in metric terms and, since 1985, has been exactly 4.54609 litres. Expressing flow "per day" arose naturally from water-utility billing and reservoir management, where daily throughput is the practical accounting period.

Law and Notable Facts

The Imperial gallon remains a legally recognised unit in the United Kingdom and several Commonwealth nations, distinct from the smaller US gallon (3.785411784 L exactly). Because of this, an Imperial gallon per day is about 20% larger than a US gallon per day (1 imp gal/d ≈ 1.20095 US gal/d), a difference that matters when reading equipment specified in the other system.

Real-World Examples and Conversions

• A typical UK household uses on the order of 100 Imperial gallons per day (about 455 litres), which is roughly 0.00526 L/s.
• A small trickling borehole yielding 1,000 imp gal/d supplies about 4,546 litres daily, or roughly 0.0526 L/s.
• Converting to metric daily volume: 1 imp gal/d = 4.54609 litres per day.
• 1,000,000 imp gal/d (a common water-treatment plant rating) equals about 52.6 L/s, or roughly 4.546 megalitres per day.

What is Cubic Centimeters per second?

Cubic centimeters per second (cc/s or $\text{cm}^3/\text{s}$) is a unit of volumetric flow rate. It describes the volume of a substance that passes through a given area per unit of time. In this case, it represents the volume in cubic centimeters that flows every second. This unit is often used when dealing with small flow rates, as cubic meters per second would be too large to be practical.

Understanding Cubic Centimeters

A cubic centimeter ($cm^3$) is a unit of volume equivalent to a milliliter (mL). Imagine a cube with each side measuring one centimeter. The space contained within that cube is one cubic centimeter.

Defining "Per Second"

The "per second" part of the unit indicates the rate at which the cubic centimeters are flowing. So, 1 cc/s means one cubic centimeter of a substance is passing a specific point every second.

Formula for Volumetric Flow Rate

The volumetric flow rate (Q) can be calculated using the following formula:

$$Q = \frac{V}{t}$$

Where:

• $Q$ = Volumetric flow rate (in $\text{cm}^3/\text{s}$)
• $V$ = Volume (in $\text{cm}^3$)
• $t$ = Time (in seconds)

Relationship to Other Units

Cubic centimeters per second can be converted to other units of flow rate. Here are a few common conversions:

• 1 $\text{cm}^3/\text{s}$ = 0.000001 $\text{m}^3/\text{s}$ (cubic meters per second)
• 1 $\text{cm}^3/\text{s}$ ≈ 0.061 $\text{in}^3/\text{s}$ (cubic inches per second)
• 1 $\text{cm}^3/\text{s}$ = 1 $\text{mL/s}$ (milliliters per second)

Applications in the Real World

While there isn't a specific "law" directly associated with cubic centimeters per second, it's a fundamental unit in fluid mechanics and is used extensively in various fields:

• Medicine: Measuring the flow rate of intravenous (IV) fluids, where precise and relatively small volumes are crucial. For example, administering medication at a rate of 0.5 cc/s.
• Chemistry: Controlling the flow rate of reactants in microfluidic devices and lab experiments. For example, dispensing a reagent at a flow rate of 2 cc/s into a reaction chamber.
• Engineering: Testing the flow rate of fuel injectors in engines. Fuel injector flow rates are critical and are measured in terms of volume per time, such as 15 cc/s.
• 3D Printing: Regulating the extrusion rate of material in some 3D printing processes. The rate at which filament extrudes could be controlled at levels of 1-5 cc/s.
• HVAC Systems: Measuring air flow rates in small ducts or vents.

Relevant Physical Laws and Concepts

The concept of cubic centimeters per second ties into several important physical laws:

• Continuity Equation: This equation states that for incompressible fluids, the mass flow rate is constant throughout a closed system. The continuity equation is expressed as:

  $A_1v_1 = A_2v_2$

  where $A$ is the cross-sectional area and $v$ is the flow velocity.

  Khan Academy's explanation of the Continuity Equation further details the relationship between area, velocity, and flow rate.

• Bernoulli's Principle: This principle relates the pressure, velocity, and height of a fluid in a flowing system. It states that an increase in the speed of a fluid occurs simultaneously with a decrease in pressure or a decrease in the fluid's potential energy.

  More information on Bernoulli's Principle can be found here.