This article appeared in Machine Design and has been published here with permission.
From automotive and motorsports to aerospace, additive manufacturing (AM) has allowed fluid dynamics to go beyond what has been achievable using conventional manufacturing processes. AM enables engineers to produce optimized designs and create fluid flow systems that are superior in terms of performance, efficiency and reliability.
In an upcoming Machine Design webcast on Jan. 21, Antonio Pellegrino, project leader of the LHCb Experiment at CERN, and Thomas Verelst, 3D Systems applications engineer, will discuss how AM is enabling advancements in manufacturing and beyond. Registration is available at this link.
CERN is the Switzerland-based European organization that operates the Large Hadron Collider (LHC), the world’s largest particle collider. CERN partnered with 3D Systems’ Application Innovation Group to redesign and manufacture titanium cool-bars for LHC experiments. AM enabled the partners to overcome several challenges associated with the parts, which are used to cool the detection area to −40°C to preserve particle reactions for study.
Chief among the challenges was space: The cool-bars had to fit into a limited space while still dissipating enough heat. They had to achieve temperature uniformity over the length of a photo-detection strip, which measures 140 meters in length and less than 2 mm in width. All while meeting flatness specifications for detector efficiency and resolution.
Based on these requirements, the partners conceived of the perfect part design. “This design was so beautiful, but it was not producible in the usual ways,” said Pellegrino.
The system designed by CERN and 3D Systems manufactured more than 300 units of the titanium cool-bars that met the necessary specifications. The full case study and specifications can be found here.
Flowing Across Industry Segments
The benefits of AM in fluid flow systems extend well beyond CERN. Potential uses include heat exchangers, integrated cooling, propulsion systems and fuel injectors. Additive manufacturing can enable the production of more lightweight structures thanks to optimized geometries. This is especially crucial in applications like propulsion systems and fuel injectors, where excess weight can drive up operating costs.
In designing a liquid rocket engine injector, for example, the German Space Center (DLR), in cooperation with the 3D Systems Customer Innovation Center, was able to consolidate 30 components into a single part which reduced the final part weight by 10%. The consolidated design also eliminated points of failure in the original system, which improved system performance. The 3D printed fuel injector also integrated certain features, like pressure and temperature sensor channels, which resulted in superior cooling and combustion performance.
“Based on the success of space-related initiatives involving DMP, we thought that 3D Systems was perfectly suited for providing the design-for-manufacturing aspects of the injector head, with an eye on new possibilities for sensor integration and fuel and coolant distribution,” said Markus Kuhn, manager of the injector head project at DLR.
A Better Flow
AM also can improve the efficiency of fluid flow applications by improving fluid dynamics. Most conventional manufacturing processes favor designs with sharp corners, which can trap fluid moving through internal channels in stagnant zones. This leads to pressure loss and reduces efficiency. Design for AM can eliminate these troublesome design features and create internal channels that are optimized for fluid dynamics. These benefits can be seen most clearly in fluid manifolds in semiconductor machinery and microfluidic devices used in research labs.
It is possible to design fluid flow systems with intentional turbulence to achieve peak cooling. In heat exchangers, for instance, built-in turbulence can increase thermal transfer, which can be useful in refrigeration appliances, energy generation and many other applications. AM enables engineers and fluid flow specialists to base designs off of fluid dynamics instead of manufacturing limitations.
Additive manufacturing is improving fluid flow applications by offering improved manufacturability through part consolidation, superior efficiency through weight reduction and mixing efficiency, and better space utilization. This is true in virtually all fluid dynamics areas, whether you are 3D printing metal cool-bars for the LHC, a fuel injector or a plastic microfluidic device with tiny channels.
