An example enclosure includes a top portion, a bottom portion, and at least one heat generating module adjacent the top portion of the enclosure. The heat generating module includes an inlet side, an outlet side, a heat generating component and an internal fan. The enclosure also includes a heat collector positioned adjacent the outlet side of the heat generating module to collect warm air from the outlet side of the heat generating module and divert the warm air to the bottom portion of the enclosure to mix with cooler air. The internal fan of the heat generating module draws the mixed air into the heat generating module to create an airflow loop within the enclosure to cool the heat generating component without a heat sink, a heat exchanger, or a fan external to the heat generating module. Other example enclosures and methods of managing heat inside enclosures are also disclosed.