Spring-loaded doors to prevent air recirculation without need for additional space

The present disclosure relates, in some embodiments, to modular information handling systems configured to automatically adjust coolant flow upon insertion and/or removal of heat-releasing elements (e.g., blades). A system may comprise, for example, a chassis at least partially defining a cavity, at least one fan in fluid communication with the cavity and operable to move coolant through at least a portion of the cavity, and one or more bays. Each of the one or more bays (a) may be at least partially defined by a bay wall, (b) may be configured to receive a heat-releasing element, and/or (c) may comprise an obturator configured to conditionally block fluid communication between the bay and the chassis cavity, the fan, and/or a coolant, wherein the obturator allows fluid communication when a blade is present in the bay and blocks fluid communication when a blade is absent from the bay. A system may further comprise at least one heat-releasing element positioned in at least one of the one or more bays.