Circulation-Enhanced Tank Heating Using Shallow Profile Coil Bundles

Abstract

Heavy fuel oils require heated tanks to facilitate their transportation and processing. This paper proposes and investigates three- and four-level heating coil bundles. Numerical study revealed that powerful large-scale circulation of the heated fluid enhances heat transfer, delivering 16.7% and 23% improvements to the average heat transfer coefficient for the three- and four-level bundles, respectively. Furthermore, this circulation improves oil mixing and limits the variation in bulk oil temperature to − 0.3 to + 1.3 °C from the average. The study also quantified oil flow velocity near the bottom of the tank. The time-averaged horizontal components of velocity, estimated 25 mm and 50 mm above the bottom of the tank, exceed 2 mm/s and 4 mm/s, respectively. The proposed heating coil bundles feature a compact design that reduces the material and labor costs of construction and that, by occupying only a small portion of the bottom of the tank, improves accessibility, maintenance, and cleaning.

Keywords

Heating coil / Tank heating / Bundle / Convection / Large-scale circulation