초록 ▼

Method and apparatus to prevaporize and premix liquid and/or gaseous fuels with air in two stages at two different temperatures prior to combustion. The invention is directed to the entry of a finely atomized liquid fuel, such as No. 2 diesel, into an inlet end of an annular chamber. Air is mixed wi

Method and apparatus to prevaporize and premix liquid and/or gaseous fuels with air in two stages at two different temperatures prior to combustion. The invention is directed to the entry of a finely atomized liquid fuel, such as No. 2 diesel, into an inlet end of an annular chamber. Air is mixed with finely atomized liquid fuel, preferably generated by a small flow number liquid fuel nozzle, in a first chamber of the annular chamber at a first (relatively high) temperature for a relatively long residence time. The air and liquid fuel is moved into a second chamber of the annular chamber where a secondary hotter air is injected into the annular chamber by a plurality of staggered high velocity jets to prevaporize and premix the combined fuel and air mixture at a second higher temperature, but for a shorter time. The intense prevaporization and premixing make the mixture suitable for entry into a combustor, but without the need to add water or steam to keep pollutant emissions low. Alternatively, the invention may be used with a gaseous fuel and air, or the combination of liquid fuel and gaseous fuel and air. A sharp-edged film atomizer may be added to provide secondary atomization of the liquid fuel.

대표청구항 ▼

[ What is claimed:] [1.] A method of staged prevaporizing and premixing fuel and air prior to combustion in a combustor, the method comprising:providing an inlet flow of air into a first stage chamber of an annular chamber having an inlet and outlet defining a second stage chamber coannular and cont

[ What is claimed:] [1.] A method of staged prevaporizing and premixing fuel and air prior to combustion in a combustor, the method comprising:providing an inlet flow of air into a first stage chamber of an annular chamber having an inlet and outlet defining a second stage chamber coannular and contiguous to the first stage chamber;introducing a fuel into the first stage chamber of the annular chamber;atomizing the fuel into the first stage chamber;mixing the inlet flow of air and fuel at a first stage temperature for a first stage residence time; wherein the resulting fuel and air mixture is moved by the inlet flow of air into the second stage chamber;introducing secondary air into the second chamber at a second stage temperature, which is hotter than the first stage temperature;secondarily mixing the atomized fuel and air mixture that has flowed from the first chamber with the secondary air in the second stage chamber at a second stage temperature, which is at a hotter temperature than the first stage temperature, and for a second stage residence time, which is shorter than the first stage residence time, until the resulting mixture is at a substantially completely prevaporized and premixed level for combustion; anddirecting the resulting substantially completely premixed and prevaporized fuel and air mixture out the outlet of the annular chamber to the combustor.