Calculation of Gas Density and Viscosity
This engineering online PDH course contains a discussion of, and an example calculation of, the density and viscosity of a specified gas at a given temperature and pressure. In this course, the Redlich Kwong equation will be used for calculation of the compressibility factor of a gas. The Sutherland formula will be discussed and used in example calculations. Another method for calculating the viscosity of air at a specified temperature and pressure will also be presented and discussed.
The density and/or viscosity of a gas is often needed for some other calculation, such as pipe flow or heat exchanger calculations. If the gas temperature is high relative to its critical temperature and the gas pressure is low relative to its critical pressure, then it can be treated as an ideal gas and its density can be calculated at a specified temperature and pressure using the ideal gas law. If the density of a gas is needed at a temperature and pressure at which it cannot be treated as an ideal gas law, however, then the compressibility factor of the gas must be calculated and used in calculating its density. The Sutherland formula can be used to calculate the viscosity of a gas at a specified temperature and pressure if the Sutherland constants are available for the gas.
This 2 PDH online course is intended for chemical, mechanical and environmental engineers. After completing this course, you will have knowledge about methods for calculating the density and viscosity of a gas at specified temperature and pressure.
This PE continuing education course is intended to provide you with the following specific knowledge and skills:
- Ability to calculate the density of a gas of known molecular weight at a specified temperature and pressure at which the gas can be treated as an ideal gas
- Ability to calculate the compressibility factor for a gas at a specified temperature and pressure, using the Redlich-Kwong equation, if the molecular weight, critical temperature and critical pressure of the gas are known.
- Ability to calculate the density of a gas at a specified temperature and pressure for which the gas cannot be treated as an ideal gas, if the molecular weight, critical temperature and critical pressure of the gas are known.
- Ability to calculate the viscosity of a gas at a specified temperature if the Sutherland constant for the gas is known and the viscosity of the gas at a suitable reference temperature is known.
- Ability to calculate the viscosity of air at specified air temperature and pressure.
- Ability to make all of the calculations described in these learning objectives using either U.S. or S.I. units.
In this professional engineering CEU course, you need to review the course document titled, “Calculation of Gas Density and Viscosity”. In addition, you need to review the Excel spreadsheet titled, "Real Gas Density Calculators_US or SI units".
Real Gas Density Calculators_US or SI units (43 KB)
Once you complete your course review, you need to take a multiple-choice quiz consisting of fifteen (15) questions to earn 2 PDH credits. The quiz will be based on both documents.
Upon successful completion of the quiz, print your Certificate of Completion instantly. (Note: if you are paying by check or money order, you will be able to print it after we receive your payment.) For your convenience, we will also email it to you. Please note that you can log in to your account at any time to access and print your Certificate of Completion.