Electronic Enclosure Thermal Management

BGAs are dissipating more heat as do their supporting chipsets. Rack space always seems to be at a premium. We get it, your customers are asking you for greater performance in less rack space.

Thermal management and dissipation are getting more complex with ever-increasing processing speeds and power requirements. The denser the heat dissipation and the smaller the volume for it to dissipate into, the more problematic cooling becomes.

In rack mount system enclosures typical conduction between a BGA and its COTS heatsink may not be adequate. AS power consumption rises, heatsinks’ footprint expands, and heat pipes, vapor chambers, or phase change materials get incorporated into custom heatsinks.

Whether fans or blowers, airflow never follows a linear flow from intake to exhaust. Contrary to what one might imagine, airflow is never linear and will do its utmost to avoid heatsinks, tall components, SIMMs, DIMMs, plug-in cards, etc., anything that will affect slight pressure changes in a pathway.

Dodging heatsinks, not there’s a problem. Depending on your board’s topology, heat density, and distributive area, there are several methods that can more cost-effectively manage this otherwise problematic effect of avoidance.

PCB component placement is an early and essential conversation before your designer begins component placement. This can benefit multiple strategies. This collaborative action can coincide with front and rear panel component placement. Employing the Bernoulli Principle may also provide benefits. Air walls and chambers can play a role.

Then there’s FEA, which, in our experience provides misleading information in force air convection enclosures. FEA does a better job with conduction applications or where its analysis is of fluids (hydraulics, resins, etc.).

In pre-routed PCB vs. thermal management collaborative discussions, we can provide ideas and insight into where there may be dead spots, turbulence, increasing air velocity in specific locations, strategies for managing the highest amount and velocity of air through heatsinks, and more. When this kind of collaborative discussion takes place near the onset of system architecture and PCB conceptualization it benefits concurrent engineering between our two companies and reduces the risk of needing a respin to meet performance requirements.