Pulse combustor apparatus

A pulsating dryer adapted for removing heat from combustion products produced by combustion of a fuel, comprising:

• a drying tube having two open ends, one end of which receives said combustion products and the other end of which exhausts said combustion products;
• and
• heat removal means for removing heat from said drying tube, said heat removal means coupling said drying tube at a location three fourths the length of said drying tube away from the end of said drying tube receiving said combustion products.

An improved combustor apparatus for continuously burning fuel while subjecting the burning fuel to acoustic pressure and to acoustic velocity pulsations which increase the rate of combustion and allow the use of less combustion air than would be required in the absence of such pulsations, said apparatus comprising:

• a combustor tube having a predetermined length and having open opposite ends which define acoustic boundary conditions permitting said tube to support natural longitudinal modes of acoustic oscillation;
• and
• means defining a continuous combustion zone within said tube for burning fuel and combustion air to generate heat at a particular location which excites a natural longitudinal mode of acoustic oscillation, the particular location being within said tube where the acoustic pressure pulsations lag the acoustic velocity pulsations by approximately one quarter period of the excited mode of acoustic oscillation.

An improved combustor apparatus for continuously burning fuel while subjecting the burning fuel both to acoustic pressure pulsations and to acoustic velocity pulsations due to acoustic oscillation maintained in the combustor apparatus by virtue of such continuous burning of fuel, said apparatus comprising:

• combustor tube means for supporting natural longitudinal modes of acoustic oscillation;
• and
• combustion zone means for defining at least one highly localized continuous combustion zone in said combustor tube means to excite acoustic oscillation in said combustor tube means which subjects said combustion zone both to acoustic pressure pulsations and to acoustic velocity pulsations whose amplitudes are significantly greater than zero but are less than their maximum values, said oscillation having at least one acoustic pressure node and at least one acoustic pressure anti-node and said combustion zone means being located approximately half and distance between the acoustic pressure node and the acoustic pressure anti-node where the acoustic pressure oscillation lags the acoustic velocity oscillation by approximately one quarter period of the acoustic oscillation.