
3D printed nozzle has multiple jets for cooling system
Researchers at the University of Illinois at Urbana-Champaign have demonstrated a new type of air jet system for thermal cooling of electronics.
The team used 3D printing to create a nozzle that can direct high-speed air onto multiple electronics hot spots, in this case from allium nitride (GaN) transisors. The researchers manufactured the cooling system from strong polymer materials that can withstand the harsh conditions associated with high-speed air jets.
The jets deliver a high speed airflow at 42 to 195 m/s onto working GaN devices mounted on a printed circuit board (PCB). This provides cooling heat fluxes of up to 58.4 W/cm2 , cooling rates of up to 6.6 °C/s, and convective heat transfer coefficient ranging from 5.2 to 17.0 kW/( m2⋅K ).
The cooling performance is comparable to that of jet coolers made from other materials and manufacturing technologies, but using 3D printing allows more design freedom and geometric complexity. The team tested out three different packaging configurations, each enabled by a different jet cooler design that is customized for different types of packaging configurations: Cooler 1 directs two parallel impinging jets onto the top side of two devices; cooler 2 directs two air jets onto the front side and two air jets onto the back side of two devices; and cooler 3 directs air jets onto the front side of four devices mounted on parallel adjacent circuit boards.
Another benefit is the ability to consolidate multiple components into a single part. The team combined the nozzles, fluidic delivery system and flow distributor within a volume of 80 mm ×80 mm ×100 mm.
“The design freedom of additive manufacturing allows us to create cooling solutions that have sizes and shapes not previously possible,” said William King, Andersen Chair and Professor of Mechanical Science and Engineering. “This really opens up a new world of opportunities for thermal management.”
The research focused on heat removal from high-power electronic devices. “The acute thermal management problems of high-power electronic devices appear in a host of applications, especially in modern data centers as well as electric vehicles including aircraft, automotive, and off-road vehicles,” said Nenad Miljkovic, Associate Professor of Mechanical Science and Engineering at Illinois.
