New Heat Exchanger Design

Applying hiTRAN® Thermal Systems at the design stage maximises the benefits of the technology and offers substantial reductions in capital and installed costs.  Many heat exchanger designs benefit from the application of hiTRAN® Thermal Systems and the opportunities can be quickly and easily assessed via popular software packages such as Aspen.

hiTRAN® Thermal Systems benefit any duty where the main heat transfer resistance is on the tubeside, reducing the required surface area.  Many common problems found in the design of heat exchangers can be overcome, such as:

  • Low tubeside heat transfer coefficients due to laminar flow
  • Inefficiency caused by a requirement for a single pass arrangement
  • Uncertainty of prediction in laminar and transitional flows
  • Low wall temperatures in systems with high pour points
  • High wall temperatures in systems with temperature sensitive fluids
  • Mist flow conditions in boiling systems at high vapour fraction
  • Poor shellside characteristics caused by large shell diameters (shell and tube heat exchangers)
  • High fan costs and large power requirements caused by large bundle sizes (air-cooled heat exchangers)

hiTRAN® Thermal Systems are routinely applied to both air-cooled and shell and tube heat exchangers, delivering the following benefits:

  • Reduced heat transfer area
  • Effective use of pressure drop
  • Reduced number of parallel or series units
  • Reduced size and weight
  • Reduced capital cost
  • Reduced installed costs
  • Reduced operating and maintenance costs
  • Design performance maintained in many fouling services

Examples illustrating the effectiveness of hiTRAN® Thermal Systems in new heat exchanger designs can be accessed via the following links:

hiTRAN enhanced Shell and Tube heat exchanger >>

hiTRAN enhanced Air Cooled lube oil cooler >>

hiTRAN® Thermal Systems have a unique variable geometry construction that permits the designer to optimise the heat transfer performance within pressure loss allowance. One or two-pass designs are usually sufficient to achieve the required performance, and are more economic to fabricate.

In shell and tube heat exchangers, hiTRAN® Thermal Systems can be combined with shellside enhancements to create a compact overall package.  Examples of compatible shellside enhancements are low-fin tubes, special boiling surfaces, helical baffles and grid-type baffles.  CALGAVIN engineers have experience of exploiting synergies with these technologies to create very high performance heat exchanger designs.

By reducing fluid residence time at the tube wall, hiTRAN® Thermal Systems inhibit or eliminate surface fouling where this is caused by thermal degradation, particle deposition or crystallisation. Using the technology to control surface temperature allows the designer to achieve higher heat flux duties.

hiTRAN® Thermal Systems are easily fitted at the heat exchanger manufacturer’s workshop.  The elements can also be easily removed at site for inspection and cleaning purposes.

Angola, Floating production

‘DALIA’ Angola, FPSO, hiTRAN / Helical baffles. DKME/Samsung, Courtesy: Total Oil

OPTIMUM DESIGN: A four-fold increase in overall heat transfer was achieved in the design of heat exchangers for this FPSO (see more detail).  In an environment where space and weight are at a premium, the corresponding benefits of reduced exchanger size, more compact piping runs and minimised controls led to significant reductions in installed costs.