Abstract: A method and apparatus for cooling electronic or other devices by bringing the device to be cooled into contact with one face of a cold plate having high thermal conductivity; and applying a plurality of liquid jets of a liquid coolant to the opposite face of the cold plate perpendicularly thereto and at spaced location thereon. The plurality of liquid jets are applied in pulses as pulsatile jets. The liquid coolant is also circulated in a pulsatile manner as a planar-flow liquid in contact with and parallel to the opposite face of the cold plate, such that the plurality of pulsatile jets of the liquid coolant flow as immersed jet streams through the planar-flow liquid coolant circulated in contact with and parallel to the opposite face of the cold plate.