Metal Additive Helps Overcome Tough Electronics Cooling Challenge

Menu
Package for military electronics system

Man-carried military communication systems often consume large amounts of power. The heat must be removed from the electronics package to avoid frying sensitive electronic components. The package typically is designed to be carried in a backpack which often puts difficult constraints on the form factor and weight of the system. A military system integrator approached Additive Design Consultancy with the challenge of providing a thermal management solution for a 14 by 10 by 5 inch system. The difficulty of this application was increased by the fact that the printed circuit boards (PCBs) that generate most of the heat are mounted on one of the 14 by 10 inch surfaces, yet to maintain the proper form factor, the external fans cannot be mounted on that surface. Another challenge was that the package must be relatively thin and light in order to fit into the backpack of the soldier who carries it on the battlefield.

Square columns used in 14 by 10 inch wall that mounts PCBs

In this case, the original design for the package was a machined aluminum box with external fans. “Before sending us this project, our customer had previously talked to several design consultancies that had determined that the interior of the package could not be cooled simply by transmitting heat through the solid aluminum walls of the device,” said Adam Arnold, Director of Additive Design Consultantcy. “Liquid cooling provided a potential alternative, but a conventional liquid cooling solution would have driven up the cost and weight of the package.” Additive Design Consultancy specializes in exploiting the new design rules offered by additive manufacturing to push past existing structural, fluid and thermal performance boundaries. In this case, Additive Design Consultancy engineers had the idea of printing the walls of the package with internal cooling channels that can be filled with a liquid coolant that efficiently conducts heat to the heat sinks mounted on adjacent walls.

X lattice used in the adjacent walls of package

The system integrator provided Additive Design Consultantcy with the thermal and structural requirements for the package. Additive Design Consultancy engineers took advantage of the design freedom provided by additive manufacturing by starting from blank space and iterating to an optimized design. Their objective was to leave as much room as possible inside the walls of the package for a cooling channel while meeting the structural and weight requirements. They took advantage of the design freedom offered by additive manufacturing to ignore manufacturability rules such as maintaining walls of uniform thickness, avoiding internal voids, etc.

Thermal simulation shows that the new design (lower right) maintains internal electronic components at a much lower temperature than the original design (upper left)

Additive Design Consultancy engineers defined the starting geometry with an external shape including mounting surfaces as defined by the systems integrator then used engineering judgement to remove material from the interior of the rectangle. They carefully checked each proposed design to ensure that the interior void is contiguous and that the final part shape is able to support the loads provided by the system integrator. They defined two types of lattice structures including a square column-based lattice for the larger wall that mounts the PCBs and an X lattice on the adjacent walls. The engineers evaluated hundreds of possible design configurations while iterating to a design that provides the best possible thermal performance within the required geometrical and structural constraints.

“Additive manufacturing provides virtually limitless design freedom, making it possible to build very complex heterogeneous structures that would be too expensive to produce with conventional methods,” Arnold said. “In this case, additive manufacturing made it possible to provide an internal cooling system without paying a cost penalty compared to a much simpler structure. The end result is a package that dramatically improves thermal management performance while meeting structural requirements without an increase in weight. The use of liquid cooling to conduct heat from the PCBs to the external fans reduces the maximum temperature inside the box from 125F to 96F. Even greater thermal performance could have been achieved by using an external lattice on the package to increase the surface area of the package which in turn would have increased heat transfer to the air.”

gastautor
gastautor
  • Software Testversionen
Juli 15, 2021
Evaluierungsanfrage: PCB / IC Design Software CR-8000

CR-8000 ist eine Suite von Anwendungen, die den gesamten Zyklus des PCB-Engineerings abdecken: von der Architekturplanung über das Engineering auf Systemebene und die Optimierung bis hin zur physikalischen Implementierung in 2D/3D und der Datenaufbereitung für die Fertigung. CR-8000 umfasst die Module Design Force und Design Gateway sowie weitere spezifische Module.

Jetzt Anmelden
Evalierungsanfrage
  • Products
Juli 14, 2021
CR-8000 Release 2021 - Neue Funktionen

Version 2021 von CR-8000 bietet mehr als 150 Verbesserungen in der gesamten Software-Suite, angefangen bei der Architekturplanung, über den Aufbau und die Verifikation von Systemschaltplänen, 3D-Multi-Board- und Advanced-Packaging-Layout bis hin zur gezielten Aufbereitung von Fertigungsausgaben

Read now
  • Presse-Information
Juli 07, 2021
CR-8000 Release 2021

CR-8000 von Zuken erweitert PCB-Design auf Systemebene durch Verbesserungen bei Analogsimulation, SI-Analyse und intelligentem Layout und Routing

Read now
CR-8000 von Zuken erweitert PCB-Design auf Systemebene durch Verbesserungen bei Analogsimulation, SI-Analyse und intelligentem Layout und Routing
  • Blog
Juni 03, 2021
Ist das 3D Elektronik Design auf der Höhe der Zeit?

Viele Jahre lang war das Layout einer Leiterplatte in 2D für die meisten Mainstream-Technologien ausreichend. Heute stehen Produktentwickler im Elektronikbereich jedoch vor neuen Herausforderungen, ausgelöst durch Megatrends wie beispielsweise das Internet of Things. Können die heutigen CAD-Tools also die neuen Anforderungen erfüllen und die Vorteile der neuen Technologien ausschöpfen?

Read now