A heat sink uses a pump assembly to generate a radial magnetic field. Pipes arranged to house a portion of a first channel and a portion of a second channel are formed in the heat sink. The direction of fluid flow in the first channel and the direction of fluid flow in the second channel is dependent on the radial magnetic field. The radial magnetic field causes fluid in the first channel to flow toward a heat source and fluid in the second channel to flow away from the heat source, thereby resulting in heat transfer between the first and second channels and between the heat sink and the respective first and second channels. The heat sink may also use a heat exchanger assembly that is connected to the heat source, where the heat exchanger assembly is formed of a plurality of channels that each propagate fluid in one of the directions of the first channel and the second channel.