Mixing device for mixing fuel and air and furnace with a mixing device

Abstract

Mixing devices for mixing fuel and air for a premix burner or furnace and furnaces (e.g., premix) with mixing devices. Furnaces may be for heating an occupied space, and may produce lower NOx emissions. A mixing device may be located within an inlet tube, may have a surface that is perpendicular to the direction of fuel flow or that forms a circle, or may have two surfaces held at substantially opposite angles to induce swirl. A portion of the mixing device may extend over an orifice of the fuel injector. A mixing device may be attached to the fuel injector, may be made from a piece of sheet metal, and may have a hole for attachment to the fuel injector. Mixing devices may have a center, two arms, and two ends, which may be separated by bends. A burner plate may be sandwiched between surfaces to allow for expansion.

Description

RELATED PATENT APPLICATIONS[0001]This patent application claims priority to U.S. patent application Ser. No. 12 / 793,318, filed on Jun. 3, 2010, titled PREMIX FURNACE AND METHODS OF MIXING AIR AND FUEL AND IMPROVING COMBUSTION STABILITY, naming four of the same inventors and having the same assignee as listed above, which claims priority to Provisional Patent Application No. 61 / 183,934, filed on Jun. 3, 2009, titled LOW NOx FURNACE AND METHODS OF MAKING AND CONTROLLING SAME, naming four of the same inventors that are listed above. The contents of both of these priority patent applications are incorporated herein by reference. Certain terms, however, may be used differently in the Provisional Patent Application.FIELD OF THE INVENTION[0002]This invention relates to premix burners, furnaces, and methods of making and improving such things. Particular embodiments concern fuel burner systems and furnaces that produce less NOx emissions than alternative burners or furnaces.BACKGROUND OF TH...

AI Technical Summary

Benefits of technology

This approach significantly reduces NOx emissions, achieves quieter operation, and ensures reliable starting under varying conditions by promoting a homogeneous air-fuel mixture and optimizing combustion parameters.

Problems solved by technology

Such processes, however, have resulted in the production of a certain amount of oxides of Nitrogen (NOx) during the combustion process.

But premix burners have been plagued with noise resulting in oscillations of combustion and flow that have prevented premix burners from becoming workable in furnaces for occupied structures.

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