In April 2025, LinusTechTips visited NASA's Langley Research Center at the invitation of the Flow Physics and Control Branch to seek an answer to the question: how far does a case fan have to be from a flat surface?
The article - authored by Dr.Louis Edelman - delves deeper into the test design and components, expanding on the approaches and methods used.
Another tip: Blowing air onto a component, instead of sucking it away, is much more effective for cooling. Basically if you put your hand where the cooled component is you should be able to feel the airflow.
In practice this meant flipping the "exhaust" fans in one of my systems. It resulted in temperatures that were consistently a few degrees lower. Note in this instance there wasn't any ducting involved.
Yes, positive pressure is also essential for keeping dust off components, which becomes insulating if left unchecked. Make sure intake fans have filters and you're golden.
The article - authored by Dr.Louis Edelman - delves deeper into the test design and components, expanding on the approaches and methods used.
In practice this meant flipping the "exhaust" fans in one of my systems. It resulted in temperatures that were consistently a few degrees lower. Note in this instance there wasn't any ducting involved.