within the cavity frictional forces developed by agitated molecules of the fluid convert the mechanical energy of motion into heat the heat thus generated moves uniformly throughout the cylindrically shaped block and heat transfer fluid is circulated through a circumferential passageway contiguous to substantially all of the outer cylindrical surface of the block and absorbs the heat generated inside the cavity the heated fluid is then conducted to a remote heat transfer station an electrical control circuit governs the sequencing of heat demand heat production and heat transfer cycles application_number US 93420586 A description a preferred embodiment of the improved flameless heat source 10 is shown in a side elevation view in fig1 the features shown are a housing 11 a power means such as an electric motor 12 connected to a power source that provides 220 vac single or triple phase not shown electronic control circuitry 80 combustionless heat source block 50 a belt 13 connecting motor 12 to block 50 through appropriate pulleys 89 circulator suction pump 17 connected to the power source insulated fluid transporting lines 18 heat exchanger 20 and heat distribution means 21 fig2 shows an end elevation view of the system shown in fig1 with fluid transporting lines.