Internal combustion engine having manifold and combustion surfaces coated with a foam
AssigneeChevron Research Company
InventorJay D. Rynbrandt
Life of this patent
Estimating the term…
Abstract
For the more efficient operation of both spark- and compression-ignited internal combustion engines, and/or control of octane requirement increase in spark-ignited internal combustion engines, at least a portion of the surfaces of the intake manifold exposed to the fuel-air mixture, and/or the combustion chamber exposed to combustion, are fabricated from coated with a material having the combination of thermal conductance and thermal penetration which permits the temperature of said surface during the combustion process to be in excess of the temperature at which deposits form and said surface storing insufficient heat to substantially raise the temperature of the incoming air-fuel charge during the engine intake and compression stroke.
Claims11
In an internal combustion engine comprising a combustion chamber having a surface exposed to combustion, the improvement which comprises at least a portion of said surface, having a combination of a thermal conductance and a thermal penetration which permits the temperature of said surface during the combustion process to be in excess of the temperature at which deposits form, said surface storing insufficient heat to substantially raise the temperature of the incoming air-fuel charge during the engine intake stroke and compression stroke, wherein said surface portion has a thermal penetration expressed as .sqroot.K.rho.C of less than about 600 J/m.sup.2 .degree.Ksec.sup.1/2, and a thermal conductance expressed as K/d of at least about 2000 J/m.sup.2 .degree.Ksec, and the product of the thermal penetration times thermal conductance is less than about 3.times.10.sup.6 J.sup.2 /m.sup.4 .degree.K.sup.2 sec.sup.3/2, and said surface portion is a thermally stable, resinous syntactic foam comprising about 40 to 70% volume of inorganic, hollow microspheres, in a matrix comprising a composite of at least five of the group consisting of:
- (a) polyimide resin;
- (b) carbon;
- (c) silica;
- and
- (d) at least any two of the group consisting of boron, aluminum, and the oxides, nitrides, and carbides of silicon, titanium, chromium, tantalum, niobium, and zinc.
Dependencies are inferred from the claim text.