Pneumoacoustic fuel-injection nozzles

Purpose

Development of a new type of fuel-injection nozzles for burning heavy fuels in steam and hot-water boilers and other heat plants.

Degree of readiness Basic design of a pneumoacoustic fuel-injection nozzle

Prototypes of pneumoacoustic fuel-injection nozzles are developed and manufactured, and full-scale tests of these devices are performed. The efficiency of the pneumoacoustic nozzles is compared with that of the conventional steam-mechanical atomizing burners. It is shown that, in the rated conditions when fuel is supplied under a pressure of 2.5 to 3.5 MPa, the pneumoacoustic nozzles provide drops twice as small as those obtained with the steam-mechanical atomizing burners. Under partial loads and lower pressures of fuel supply, the difference in the drop sizes can be fourfold or even sixfold.

The pneumoacoustic fuel-injection nozzles can operate in a wide control range with a constant excess-air coefficient (~1.05), whereas the steam-mechanical atomizing burners operate under partial loads at higher values of this coefficient, which leads to considerable loss of heat. Fuel-injection nozzle: separate parts and assembly

Besides, for the steam-mechanical burners, a decrease in the fuel pressure below 0.8 MPa leads to unstable burning conditions, while pneumoacoustic nozzles provide a stable operation up to 0.1 MPa.

Pneumoacoustic fuel-injection nozzles make it possible to increase the efficiency of a boiler by 0.7% under a rated load and by almost 2% under partial loads. The use of pneumoacoustic nozzles allows one to reduce the content of nitrogen oxides in the flue gas by 6-12%, the fuel consumption by 2-2.5%, and the atomizing steam (air) consumption by 30-40%.

The Acoustics Institute accomplishes manufacturing of the device upon a request. Pneumoacoustic fuel-injection nozzles are delivered with a complete set of equipment. The assistance in mounting the devices is provided.