Low NO.sub.x liquid fuel oil atomizer spray plate and fabrication method thereof

Abstract

An atomizer spray plate is provided for discharging fuel oil. The spray plate has a cylindrical rear portion and a conical front portion. A frusto-conical whirl chamber extends from the rear portion to the front portion with a decreasing radius. The rear portion includes a number of whirl slots extending radially inward from an outboard region of the rear portion to the whirl chamber to provide the fuel oil with rotational energy. A discharge slot is provided in the front portion of the atomizer spray plate for receiving the fuel oil from the whirl chamber with the rotational energy. The discharge slot includes a cylindrical through-hole with a diameter d, and a transverse slot having a semi-circular cross-section with radius r. The discharge slot can be easily and economically fabricated with two shaping steps since there is no need to precisely set any particular non-right angle for walls of the discharge slot. Yet, the discharge slot provides a spray pattern with lateral fuel-rich zones separated by a central fuel-lean zone which inhibits the formation of NO.sub.x by reducing the peak combustion flame temperature generated by the spray pattern.

Dependencies are inferred from the claim text.