Performance

hiTRAN Thermal Systems improve performance directly, increasing tubeside heat transfer coefficients.  There are also a number of indirect performance benefits which arise from the use of this technology:

  • Increased shellside heat transfer through reductions in shell diameter
  • Improved tubeside flow distribution
  • Better control of skin temperatures for temperature-sensitive fluids
  • More consistent turndown behaviour over a wide range of Reynolds numbers

Heat  transfer and pressure drop

Graphical representation of plain tube and hiTRAN enhanced performance range

hiTRAN enhanced performance range

When fluid flows through a plain tube the fluid nearest the wall is subjected to frictional drag, which has the effect of slowing down the fluid at the wall. This laminar boundary layer can significantly reduce the tube-side heat transfer coefficient and consequently, the performance of the heat exchanger.

Inserting correctly profiled hiTRAN Matrix Elements into the tube will disrupt the laminar boundary layer, creating additional fluid shear and mixing, thereby minimizing the effects of frictional drag. hiTRAN Matrix Elements are particularly effective at enhancing heat transfer efficiency in a plain tube design operating at low Reynolds Numbers (laminar to transitional flow.) Although the heat transfer increase is greatest in the laminar flow region (up to 20 times), significant benefits can be obtained in the transitional flow regime (up to 15 times) and turbulent flow regime (up to 3 times.) Cal Gavin have installed hiTRAN Systems in heat exchangers operating in range of Reynolds number from 1 to over 100,000.

Whilst there is an increase in frictional resistance associated with hiTRAN Systems, the amount of enhancement is such that solutions can be found which offer increased heat transfer at equivalent or lower pressure drop than a plain tube.

Case studies

Improved performance is best illustrated with case studies below. Full details for any of the case studies  CASE STUDIES >>

Heating cracked bottoms and coal tar mixture

(CS15) Tar oil residue heating system in carbon black plant reaches 25 years operation – longer run times, minimum fall-off in performance while processing residue prone to polymerisation and coking CABOT CARBON

HCGO/ tempered water cooler

(CS9) New heavy cycle gas oil cooler designed with 80% reduced surface area provides consistent performance without usual sticky deposit formation IMPERIAL OIL

Methanol Synthesis tube-cooled converter

(CS8) Capacity increased in LNG condensate stabiliser reboiler by improving fluid distribution and reducing film boiling WOODSIDE OFFSHORE PETROLEUM

Heavy wax distillate cooling

(CS6) Wax crystalisation fouling eliminated in heavy wax distillate cooling service with additional benefits of 50% surface area reduction BP OIL