Internal Fans: The Future of Smartphone Electronics?

25 July, 2019

Last month, Chinese smartphone company Nubia Technology broke the mold for mobile cooling, introducing the "Red Magic 3" — its latest smartphone for the hardcore mobile gaming community.

Where traditionally weight, space and noise limitations have meant that thermal management in phones must be limited to heatsinks and cooling pipes, the Red Magic 3 is the world’s first gaming phone to incorporate a cooling fan inside the device. Controlled via an app, this fan can switch between standard and rapid cooling modes, spinning up to 14,000 rpm. According to Nubia, this (admittedly noisy solution) can reduce the temperature of the phone by up to 16 degrees when running at a heavy load.

While the likes of ASUS and Black Shark have previously offered external cooling fans for their gaming smartphones, the Red Magic 3 represents a serious feat of thermal engineering — and a potential idea for where mobile electronics could be heading in future.

As teardowns for the Red Magic 3 start to appear online, the first thing we at 6SigmaET wanted to know is: does this fan really make a difference, or is it just a gimmick designed to appeal to hardcore gamers?

A look under the hood

Taking apart the smartphone in a teardown video, YouTuber JerryRigEverything makes it clear that Nubia’s claims aren’t just a lot of hot air. The fan is suitably placed on top of a thick layer of thermal foam directly above the CPU and motherboard. This in turn is connected to a thin, metallic channel directed towards a nearby vent on the side of the phone. From both the size and positioning of these components it’s clear that the Red Magic 3’s fan is about more than just impressing gamers. In fact, some estimates have claimed that the phone’s thermal performance is up to five times better than those relying on traditional cooling methods — although a full thermal simulation would be required to test that claim.

This said, the Red Magic 3 isn’t just benefiting from its internal fan. Teardowns of the phone have revealed a whole host of traditional cooling mechanisms including a large central heat pipe running under the screen and a huge amount of pink thermal paste throughout the phone (described by one reviewer as “equivalent to a freak frosting factory explosion”).

Are internal fans the future of smartphone electronics?

Clearly the Red Magic 3 is still generating a significant amount of heat with estimates of the chipsets power dissipation of 5W. Most phones dissipate less than 3W.  Nubia is taking multiple precautions — both traditional and non-traditional — to manage its thermal output. At the same time, as a gaming phone, the Red Magic 3 is dealing with a whole host of components that would be over-and-above for any other traditional smartphone.

Not only does the phone have 12GB of RAM and 256GB of storage, but it also includes a lot of extraneous "flashiness" designed to appeal to the gaming community. This includes a strip of RGB LEDs which further adds to the  complexity of the phone.

Clearly, not all smartphones need this level of functionality, but it does raise an interesting point about the future of thermal design. As ever more ambitious and popular titles such as Call of Duty and Fortnight are being recreated for mobile, the need to process heavy graphics without lagging or overheating is going to become an increasingly common concern. At the same time, as components get smaller and more powerful there’s no reason why internal fans shouldn’t become the go-to solution for these concerns.

The Red Magic 3 may be the first attempt at this technology, but we shouldn’t be surprised to see far more internal fans popping up in gaming phones. As both the electronics and the cooling mechanisms inside these devices have become increasingly complex, accurate thermal simulation is more important than ever.

At the same time, stuffing large fans into devices shouldn’t become the go-to cooling solution. Instead, by using thermal simulation, smartphone manufacturers can find far more subtle ways to reduce the temperature of their devices, helping to improve reliability while also reducing size, weight, speed and cost for the manufacturer. While fans may sometimes be the only viable option in most high-powered gaming phones, engineers can leverage the power of CFD simulation to look for alternatives before committing to costly, noisy and bulky thermal solution.

Blog written by: Chris Aldham, Product Manager