Combustion – Process of combustion or burner operation
Patent
1991-07-31
1993-03-09
Jones, Larry
Combustion
Process of combustion or burner operation
431 12, 431333, 431335, F23D 1136
Patent
active
051922037
DESCRIPTION:
BRIEF SUMMARY
DESCRIPTION
1. Technical Field
The present invention relates to a method and apparatus for foaming and burning liquid fuel, particularly gas oils such as kerosine and light oil, in a wide range of applications from household oil stoves up to industrial furnaces.
2. Background Art
The conventional practice has been to burn a liquid fuel either directly gasified or as finely vaporized by an atomizer.
As disclosed in JP-A 1-95205, the applicant earlier proposed a completely new method of burning liquid fuel, namely a foamed fuel burning method, which expands the range over which the liquid fuel combustion rate can be regulated and overcomes the shortcomings of the pot and vaporization methods.
Further, as disclosed in JP-A 2-21106, the applicant has also proposed an apparatus for burning foamed liquid fuel in which back-flow of the fuel at the time of flame extinguishment is prevented by equipping the fuel foamer with a porous filter (element) made of a material with surface properties which give it a critical surface tension which is lower than the surface tension of the liquid fuel.
As is disclosed in JP-A 2-259311, moreover, the applicant has also proposed a method and apparatus for burning foamed liquid fuel in which a combustion chamber, a vaporization dish and a foamer are disposed close to each other, liquid fuel is supplied to the exterior of the porous element in the foamer and foaming air is supplied to the interior of the porous element, whereby the vaporization surface of the fuel is markedly increased immediately before it is burned.
Summary of the Invention
In the burning of foamed liquid fuel in the aforesaid manner, if the amount of fuel supplied is maintained constant and the amount of air supplied through the air supply pipe is increased excessively, it sometimes occurs that the fuel is converted into droplets. When this happens, the combustion becomes unstable. That is, the amount of air fed into the liquid fuel through the porous element markedly affects the foam expansion ratio of the foam and greatly affects the combustion properties of the fuel by, for example, resulting in a fuel that is not foamed but merely has bubbles dispersed therein or in a fuel that experiences the blow-through of large globs of air. Generally speaking, in the burning of foamed fuel the combustion property is affected by variation in the diameters of the bubbles constituting the foamed fuel. The mean pore diameter of the porous element constituting the fuel foamer and the apparent velocity of the foaming air (the apparent velocity calculated presuming that no porous element is present) greatly affect the stability of ignition and continuous combustion.
An object of this invention is to provide a method and apparatus for burning foamed liquid fuel wherein the uniformity and foam property of foamed fuel are stabilized, fuel vaporization is enhanced and, as a result, the stability of fuel combustion is enhanced
In this specification, the term "foam" is used to mean aggregated bubbles constituted of a film of liquid fuel surrounding a gas, specifically air. The word "uniform" as termed with respect to foam is used to mean that there is little variation in the size of the bubbles constituting the foam. The term "stability of foaming" is used to mean that the diameter of the individual foam bubbles is small and the foam expansion ratio (foam volume/liquid fuel volume) is stable and large.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertical sectional view of the essential part of an embodiment of the apparatus according to the invention.
FIG. 2 is a sectional view of the same embodiment taken along line A--A in FIG. 1.
FIG. 3(a) is a graph showing the relationship between the mean pore diameter and the air resistance of the porous element used in this invention.
FIG. 3(b) is a graph showing the relationship between the mean pore diameter of the porous element and the ignition stability.
FIG. 4 is a graph showing the relationship between the apparent foaming air velocity and the foam expansion ratio in this in
REFERENCES:
patent: 70117 (1867-10-01), Post et al.
patent: 1378689 (1921-05-01), Larson
patent: 2396577 (1946-03-01), Kittel et al.
patent: 2710652 (1955-06-01), Ambrose
patent: 4443180 (1984-04-01), LeFrois
patent: 4566877 (1986-01-01), Pazdej et al.
patent: 5051090 (1991-09-01), Anzawa et al.
patent: 5066219 (1991-11-01), Anzawa et al.
Adachi Koji
Anzawa Norio
Jones Larry
Nippon Steel Corporation
LandOfFree
Method and apparatus for burning foamed liquid fuel does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for burning foamed liquid fuel, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for burning foamed liquid fuel will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-207151