How HITRAN Thermal System work

hiTRAN® Thermal Systems consists of a unique wire frame matrix designed to promote fluid mixing and improve tube-side heat and mass transfer.

Flow disruption caused by hiTRAN element. A. Laminar Flow conditions B. Turbulence caused by the use of hiTRAN element. blue and red ink is injected into the edge of the tube. In laminar flow conditions (A) the ink stays at the edge, where the hiTRAN Element is in place (B) the turbulent motion of the fluid can be seen by the displacement of the ink.

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.

By using hiTRAN® Thermal Systems in the tube the laminar boundary layer will be disrupted, creating additional fluid shear and mixing, thereby minimizing the effects of frictional drag.

hiTRAN® Thermal Systems 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 16 times), significant benefits can be obtained in the transitional flow regime (up to 12 times) and turbulent flow regime (up to 3 times.) In fact, CALGAVIN have installed hiTRAN® Thermal Systems in heat exchangers operating between Reynolds numbers 1 to over 100,000.

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

http://www.calgavin.com/heat-exchanger-solutions/hitran-systems/how-hitran-works/