3.1
3.1.1
IN AN IDEAL WORLD
Introduction
In this section we look at the relationship between temperature and pressure for an ideal gas.
The concept of an ideal gas is very useful in engineering calculations and when representing even real world engine cycles. We explore what an ideal gas is and how real world gases may approximate the behaviour of an ideal gas. As a reminder we briefly revisit the concept of molecules and moles so that we may present the equation of state for an ideal gas.
Terms
Be able toBy the end of this section you should be familiar with terms such as:
Moles
Boyle’s Law, Charle’s Law
Equation of state for an ideal gas
Given P,V and T, determine the mass or density of an ideal gas.
3.1.2
In an ideal world
The Ormen Lange Gas Pipe
The following video link provides a fascinating introduction to the topic as we begin to investigate the properties of a gas and the relationship between temperature and pressure for an ideal gas.
If you watch the video you might like to consider, how much natural gas is exactly inside the pipeline at any one time ! Is it a gas or a liquid ?
3.1.3
In an ideal world
Pause for thought
Ormen Lange Gas Pipeline
Nyhamna
Sleipner
Easington
In the video we learnt about the Ormen Lange gas pipe, and how natural gas is now being brought ashore at Easington, just a few miles from Hull
The Langeled Pipeline is 1200KM in length with the northern leg (Approx 600KM) in 42" diameter pipe and the southern led (approx 600KM) in 44"pipe. Pressure in 205BarG, Pressure Out 120BarG, Temp Out -2oC
You might like to consider, how much natural gas is exactly inside the pipeline at any one time! Is it really a gas or a liquid?
On a smaller scale, have you thought how much gas (or liquid) is there in a bottle of propane. At what pressure is this stored?
What happens when it heats up or cools down?
3.1.4
In an ideal world
Screencast
3.1.5
In an ideal world
Review Questions
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As a measure of your understanding of this section try to answer the following questions.
What is the definition of a mole, represented in SI units as a kmol?
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As a measure of your understanding of this section try to answer the following questions.
Which properties appear in the equation of state for an ideal gas?
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As a measure of your understanding of this section try to answer the following questions.
What is the definition of the equation of state for an ideal gas
On a molar basis?
On a mass basis?
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As a measure of your understanding of this section try to answer the following questions.
What is the definition of density?
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As a measure of your understanding of this section try to answer the following questions.
How can density be evaluated from the equation of state?
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As a measure of your understanding of this section try to answer the following questions.
What is the compressibility factor used for?
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As a measure of your understanding of this section try to answer the following questions.
What is the value of the compressibility factor for an Ideal Gas?
