Session: 13-08 Heat Exchangers (II)

Paper Number: 127637

127637 - An Additively Manufactured Two-Fluid Heat Exchanger Designed With Topology Optimization Tools 

Heat exchangers are widely used in gas turbine plants for several purposes. A main use is the cooling of mineral and synthetic oils which feed the bearings of the gas turbine and other driven equipment (such as compressors, gearboxes, and generators). Traditionally shell & tube oil/air coolers have been used. However, the increased capability of additive manufacturing techniques in recent years has led to interest in the use of alternative heat exchanger designs, such as those generated with Design for Additive Manufacturing tools such as topology optimization. These design tools can result in more efficient heat exchangers with internal structures much more reminiscent of organic shapes.

Additive manufacturing techniques can enable the design and production of disruptive geometries that cannot be made with traditional manufacturing processes. Today, Powder Bed Fusion technology is one of the most widespread additive techniques for the production of metal components. However, heat exchangers for gas turbine applications introduce new challenges to the use of this technology. Two of the primary difficulties in the use of Powder Bed Fusion is the printing of materials with high thermal conductivity such as copper alloys as well as powder cleaning from any complex internal channels such as those which may be generated by topology optimization tools.

This paper describes activities performed to design, by using a proprietary topology optimization software, an oil/air cooler with significantly reduced size and pressure drop compared to an equivalent one based on a conventional design. In a potential future application on oil circuit, this could consequently result in an optimization of the lube oil circuit components, for example pumps, piping, console dimensions and weight. The cooler is manufactured using additive manufacturing techniques.

To overcome the drawbacks of gyroids-based geometry (I.e., the heat exchanger is not locally optimized for the local thermo-fluid conditions), the final topology optimized design considers the entire heat exchanger, optimizing everywhere simultaneously for local flow conditions. The final shape is inspired by biomimicry and reminiscent of a cardiovascular system where fluid flow paths are split into smaller and smaller channels to maximize heat transfer. The design was also optimized to consider manufacturability constraints such as overhang angles and minimum thickness as well as to correct for feedback from initial trial prints. 

Presenting Author: Claudio Caruso Baker Hughes

Presenting Author Biography: Master degree in Mechanical Engineering at Florence University.
Working in Baker Hughes (former GE Oil & Gas) since 2001, currently as Senior Principal Engineer in the Auxiliary Systems Engineering organization
More than 20 years of total experience in Gas Turbine Auxiliary Systems, with particular focus on Heavy Duty Gas Turbines applications and interaction/integration between fluid system, mechanical, instrumentation, control, train operability.

Authors:

Claudio Caruso Baker Hughes
Francesco Morante Baker Hughes
Giacomo Pampaloni Baker Hughes
Stefano Rossin Baker Hughes
Alessandro Canova ToffeeX
Nicola Casari ToffeeX
Thomas Rees ToffeeX