P1 estbalish the basic operating conditions of vapour compression systems UEERA0036

A collection of 60 vocabulary-style flashcards covering the history, thermodynamics, gas laws, components, and physics of refrigeration based on the provided lecture notes.

Jacob Perkins

An American engineer who in 1834 invented the apparatus that was the forerunner of modern compression systems.

Michael Faraday

Discovered the principle of absorption refrigeration in 1824 and that certain gases under constant pressure condense when cooled.

James Harrison

An Australian who in 1857 developed a refrigeration machine using a Perkins compressor and set up the world's first ice manufacturing plant.

Kelvinator

The company that produced the first automatic refrigerator for the American market by 1918.

General Electric

Introduced the first sealed, or "hermetic," automatic refrigeration unit in 1928.

Richard Mollier

Calculated the first exact vapour tables for $CO_2$ and introduced a graphic representation of properties for steam, air, and refrigerants.

Willis Carrier

Designed a humidity control in 1902 and originated the equation upon which the psychrometric chart and air conditioning is based.

Thomas Midgely

Co-developer of the refrigerant R12 in 1931 along with C.F. Kettering.

Copeland

Introduced the first successful semi-hermetic (Coplematic) field serviceable compressor in 1939.

First law of thermodynamics

Attributed to Robert Mayer and Joule, stating that heat and mechanical work are equivalent and stand in a fixed relationship.

Second law of thermodynamics

Attributed to Sadi Carnot and Rudolph Clausius, stating that wherever there is a temperature difference, a moving force can be generated.

Entropy

A term first introduced by the Frenchman Sadi Carnot within the study of thermodynamics.

Charles' Law

States that at a constant pressure the volume of gas varies directly as the absolute temperature, and at a constant volume the pressure varies directly as the absolute temperature.

Boyle's Law

States that the volume of a gas varies inversely as the pressure, provided the temperature remains constant.

Dalton's Law

States that the total pressure of a mixture of gases is the sum of the partial pressures of each of the gases in the mixture.

Ozone Theory

Presented by Professors Rowland and Molina in 1974, suggesting that CFCs were depleting the ozone layer.

Montreal Protocol

An 1887 agreement signed by industrialised countries, including Australia, for the reduction of CFC refrigerants.

Kyoto Protocol

A 1997 agreement intended to reduce worldwide global warming gas emissions.

Kigali Amendment

A 2016 amendment to the Kyoto Protocol for the phase out of HFC refrigerants to further reduce $CO_2$ emissions.

Air conditioning

The simultaneous year-round control of temperature, humidity, air purity, air movement and noise within an enclosed space.

Refrigeration

The process of removing heat energy from a product or substance by transferring it to the atmosphere.

Cycle

A series of events occurring in a specific sequence that enables continued repetition without interference.

Low-side

The part of the refrigeration system containing the low pressure refrigerant, including the RMD outlet, evaporator, and suction line.

High-side

The part of the system containing high pressure refrigerant, including the compressor discharge, condenser, and liquid receiver.

Matter

Anything that has mass and occupies space, existing as a solid, liquid, or vapour/gas.

Atom

The smallest particle of matter, consisting of a nucleus of protons and neutrons with orbiting electrons.

Molecule

A group formed from the bonding of atoms; those with different types of atoms are called compounds.

Heat

A form of energy representing the ability to do work, related to the thermal kinetic energy of molecules.

Conduction

The method of heat transfer occurring through physical contact between two objects at different temperatures.

Convection

Heat transfer by currents flowing in fluids caused by changes in pressure and temperature.

Radiation

Heat transfer by heat rays or electromagnetic waves through a vacuum or gas.

Joule

The SI unit for work and energy, commonly referred to as the kilojoule ($kJ$) in refrigeration.

Watt

The unit of power, representing the rate of work done as Joules per second ($J/s$).

Temperature

The measure of the heat intensity or heat level of a substance, directly related to the kinetic energy of its molecules.

Absolute Zero

The temperature at which all molecular movement ceases, believed to be $-273^\text{C}$ or $044K$.

Kelvin Scale

A temperature scale that sets zero at absolute zero; calculated as $K = ^\text{o}C + 273$.

Celsius Scale

A scale where water freezes at $0^\text{o}C$ and boils at $100^\text{o}C$ under standard atmospheric pressure.

Sensible Heat

Heat that causes a change in temperature of a substance that can be detected by touch and measured with a thermometer.

Specific Heat Capacity

The amount of heat that must be added or released to change the temperature of $1\,kg$ of a substance by $1\,K$.

Latent Heat

Heat that brings about a change of state with no change in temperature.

Latent heat of fusion

The heat required to change a solid to a liquid or vice versa, such as ice to water.

Latent heat of vaporisation

The amount of heat required to change a liquid to a vapour or gas at the saturation point.

Latent heat of condensation

The amount of heat required to be removed to change a vapour or gas to a liquid.

Sublimation

The process of changing a substance from a solid directly to a vapour without passing through the liquid state.

Compressor

The 'heart' of the system that creates a pressure difference to circulate refrigerant.

Condenser

A heat exchange device that rejects sensible and latent heat from the system to cause refrigerant to condense.

Liquid Receiver

A vessel designed to store liquid refrigerant after it leaves the condenser.

Refrigerant Metering Device (RMD)

A component that causes a pressure drop and regulates the flow of refrigerant into the evaporator.

Evaporator

A heat exchanger that absorbs heat, causing the refrigerant liquid to vaporise.

Discharge Line

The pipework connecting the compressor to the condenser.

Liquid Line

The pipework connecting the end of the condenser to the Refrigerant Metering Device.

Suction Line

The pipework connecting the evaporator to the compressor.

Saturated Temperature

The temperature at which a liquid will boil or a vapour will condense for a given pressure.

Saturated Liquid

A liquid at its boiling point; the addition of any heat will cause it to change state into a vapour.

Saturated Vapour

A vapour at its condensing point which can only exist when in contact with its liquid.

Superheated Vapour

A vapour at any temperature above its saturation temperature, produced by adding sensible heat after vaporisation.

Subcooled Liquid

A liquid cooled so that its temperature is reduced below its saturation temperature after condensing.

Flash Gas

Gas resulting from the instantaneous evaporation of refrigerant in an RMD to cool the remaining liquid.

Pressure

The force exerted per unit of area, expressed in Pascals ($Pa$).

Gauge Pressure

A scale calibrated to read $0\,kPa$ at atmospheric pressure, not accounting for the pressure of the atmosphere.