Abstract: A heat transfer apparatus includes a heat chamber and a heat dissipating structure coupled to the heat chamber so as to jointly form a closed thermal circuit. The heat dissipating structure includes an outlet channel that leads off from the heat chamber and issues at an end that is remote from the heat chamber into a return duct which issues into the heat chamber. The return duct has a dimension which is smaller than a dimension of the outlet channel. The heat chamber is a boiling chamber or a steam chamber and the heat dissipating structure is a channel structure having steam regions and fluid regions. The heat chamber and the heat dissipating structure together form a pulsating or oscillating heating structure mechanism.