F23L—SUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ; VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
F23L9/00—Passages or apertures for delivering secondary air for completing combustion of fuel
F23L9/04—Passages or apertures for delivering secondary air for completing combustion of fuel by discharging the air beyond the fire, i.e. nearer the smoke outlet
Un procedimiento para aumentar la fuerza calorífica de los combustibles en las máquinas térmicas con el empleo de humos, gases y subproductos de la combustión para calentar previamente el aire atmosférico admitido.