If heat energy is transferred from direct contact between a warm object and a cold object, it has been transferred by Convection.
Heat is transferred through convection, which is the large-scale movement of molecules inside gases and liquids. Conduction is used to move heat from the object to the fluid initially, but fluid motion is responsible for the bulk of the heat transfer.
The transfer of heat between two bodies by currents of moving gas or fluid is known as convection on heat transfer. In free convection, air or water rises and is replaced by a cooler parcel of air or water as it moves away from the hot body.
