Expansion Coefficient
Definition - What does Expansion Coefficient mean?
Expansion Coefficient, also known as coefficient of thermal expansion is the change in the size of an object (could be solid, liquid or in gaseous state) with the rate of change in the temperature. It generally measures the fractional change in the size of the object with the change in the temperature keeping the pressure constant. There are several types of expansion coefficients that are developed such as linear, volumetric and area thermal coefficients.
Petropedia explains Expansion Coefficient
Solids undergo maximum expansion when their surface temperature is increased by heating while they also contract when they are cooled. This response to the temperature change by any object is referred as coefficient of thermal expansion.
Coefficient of thermal expansion is used in-:
- Linear thermal expansion
- Volumetric thermal expansion
- Area thermal expansion
The coefficient of expansion for crude oil and petroleum products is expressed by the following equation:
Where
Ko , K1 and K2 depends on the type of oil used.
Below table illustrates the volumetric coefficient of thermal expansion of various liquids obtained from refineries, petrochemical industries, etc.
Liquid | Volumetric Coefficient of Expansion | |
(1/K, 1/ Degree C) | (1/ Degree F) | |
Acetic acid | 0.0011 | 0.00061 |
Acetone | 0.00143 | 0.00079 |
Ethanol | 0.00109 | 0.00061 |
Methyl Alcohol | 0.00149 | 0.00083 |
Ammonia | 0.00245 | 0.00136 |
Aniline | 0.00085 | 0.00047 |
Benzene | 0.00125 | 0.00069 |
Bromine | 0.0011 | 0.00061 |
Calcium Chloride in 5.8% solution | 0.00025 | |
Calcium Chloride in 40.9% solution | 0.00046 | |
Carbon disulfide | 0.00119 | 0.00066 |
Carbon tetrachloride | 0.00122 | 0.00068 |
Chloroform | 0.00127 | 0.00071 |
Ether | 0.0016 | 0.00089 |
Ethyl acetate | 0.00138 | 0.00077 |
Ethylene glycol | 0.00057 | 0.00032 |
Dichlorodifluoromethane refrigerant (R-12) | 0.0026 | 0.00144 |
normal Heptane | 0.00124 | 0.00069 |
Hydrochloric acid in 33.2% solution | 0.00046 | |
Isobutyl alcohol | 0.00094 | 0.00052 |
Gasoline | 0.00095 | 0.00053 |
Glycerol | 0.0005 | 0.00028 |
Kerosene and Jet fuel | 0.00099 | 0.00055 |
Mercury | 0.00018 | 0.0001 |
Methyl iodide | 0.0012 | 0.00067 |
normal Octane | 0.00114 | 0.00063 |
Lubricating Oil (unused engine oil) | 0.0007 | 0.00039 |
Olive oil | 0.0007 | |
Paraffin oil | 0.000764 | 0.00042 |
Petroleum | 0.001 | 0.00056 |
normal Pentane | 0.00158 | 0.00088 |
Phenol | 0.0009 | 0.0005 |
Potassium chloride in 24.3% solution | 0.00035 | |
Sodium chloride in 20.6% solution | 0.00041 | |
Sodium sulfate in 24% solution | 0.00041 | |
Concentrated Sulfuric acid | 0.00055 | 0.00031 |
Toluene | 0.00108 | 0.0006 |
Trichloroethylene | 0.00117 | 0.00065 |
Turpentine | 0.001 | 0.00056 |