Genie Steps: Project Conditions
I have a range of environmental conditions, what should I tell Aavid Genie?
What does the Genie mean by “Working Envelope”?
For conservative results, use the harshest potential conditions that are likely to affect your heat sink. Typically, this means the highest elevation and highest temperature that the devices or complete product will experience.
Read more about Environmental Conditions for more information on what inputs to use in the Genie.
This is the volume you have available for your heat sink. If you don’t have a fixed volume that you are working with, try using the largest preferred volume for your heat sink. Be sure to take into consideration any existing enclosures or ducts as those may dictate specific dimensions available to you.
Read more about what Aavid Genie means by working envelope
and what values to use.
How does Aavid Genie define depth?
In Aavid Genie, “depth” is the flow length of the fins. In other words, the depth is the direction perpendicular to the heat sink profile.
What does the Genie mean by “Total Load of Devices”?
Your device may be powered by 100 W but is only dissipating 20 W as heat. The 20 W is what the heat sink will need to dissipate, so that is what your input to Aavid Genie should be. Read more about how to determine Total Load of Devices
and what values to use in Aavid Genie.
I have multiple devices, what should I input as the Total Heat Source Size?
In the project conditions page, Aavid Genie allows you to customize the size of your device. This is only to get an estimation of the power density and its effect on heat spreading in the base. You should select dimensions that will generate a footprint area equivalent to the sum of the footprint area all the devices will have on your base.
Learn more about determining Total Heat Source Size in Aavid Genie
Why does Aavid Genie only apply Radiation to Natural Convection cases?
Aavid Genie will only apply the effects of radiation to heat sinks that have no forced flow or are removing heat by natural convection. This is because the effect of radiation is a noticeable portion of heat transfer during natural convection, but negligible in forced convection situations.
Should I use the Maximum Case Temperature or Thermal Resistance of my device?
It depends upon what value you have available to you, but they both will produce a maximum case temperature. If you have neither of these values, the Maximum Case Temperature may be the easier to calculate from the datasheet of your device.
Read about how to Calculate the Maximum Case Temperature
of your device.
I only have the Maximum Junction Temperature of my device, how do I calculate the Maximum Case Temperature?
Learn more how to Calculate the Maximum Case Temperature
of your device based on your device datasheet’s thermal section.
How do I know what my Maximum Pressure Drop is?
Consider what is producing your airflow. If you aren’t using a fan, you have minimal pressure drop available to you. If you are using a fan or blower, you will need to consider a fan curve (PQ Curve). If you have an air flow for a whole system, you will need to consider the other elements in your system in relation to the fan curve.