Heat Transfer Coefficient—Petroleum Fractions

For liquids other than degree API oils, multiply 

A simplified equation for the heat transfer coefficient of petroleum fractions in horizontal tubes is  

The maximum error in the range of the nomograms is 14.5%. But the simificant value in this approximation is Ap jp Y which provides a maximum error of 3.4%. 

Example for Horizontal Tubes. The heat losses from a kerosene storage tank are estimated at a maximum of 3,000,000 Btu/hr. Automatically controlled exhaust steam at 212° F is available for heating. A horizontal bayonet tube bundle consisting of 7/8-inch OD tubes on 1 1/8-inch square pitch, 12 feet long is to be inserted through an opening at the tank bottom. The kerosene has a gravity of 40° API at 60° F, and its viscosity is 1.47 cp at 100° F and 0.68 cp at 210°F. The kerosene temperature is to be maintained at 100°F. 

HORIZONTAL TUBES NATURAL. CONVECTION FIL-M COEFFICIENT FOR PETROLEUM FRACTIONS 

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Liquid viscosity is one of the most difficult properties to calculate with accuracy, yet it has an important role in the calculation of heat transfer coefficients and pressure drop. No single method is satisfactory for all temperature and viscosity ranges. We will distinguish three cases for pure hydrocarbons and petroleum fractions ... 

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