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Context. Recent observations by the Extreme Ultraviolet Imager (EUI) on boardSolar Orbiter have characterized prevalent small-scale transient brighteningsin the corona above the quiet Sun termed campfires. Aims. In this study wesearch for comparable brightenings in a numerical model and then investigatetheir relation to the magnetic field and the processes that drive these events.Methods. We use the MURaM code to solve the 3D radiation MHD equations in a boxthat stretches from the upper convection zone to the corona. The modelself-consistently produces a supergranular network of the magnetic field and ahot corona above this quiet Sun. For the comparison with the model wesynthesize the coronal emission as seen by EUI in its 174 {\AA} channel,isolate the seven strongest transient brightenings, and investigate (thechanges of) the magnetic field in and around these in detail. Results. Thetransients we isolate have a lifetime of about 2 minutes and are elongatedloop-like features with lengths around 1Mm to 4 Mm. They tend to occur atheights of about 2Mm to 5Mm above the photosphere a bit offset from magneticconcentrations that mark the bright chromospheric network and they reachtemperatures of above 1 MK. With this they very much resemble the (larger)campfires found in observations. In our model most events are energised bycomponent reconnection between (bundles of) field lines that interact atcoronal heights. In one case we find that untwisting of a highly twisted fluxrope initiates the heating. Conclusions. Based on our study we propose that themajority of campfire events found by EUI are driven by component reconnectionand our model suggests that this process contributes significantly to theheating of the corona above the quiet Sun.

Transient small-scale brightenings in the quiet solar corona: a model for campfires observed with Solar Orbiter