RU2424279C1 - Fuel - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: fuel contains ingredient liquid at working temperatures and pressure and additionally contains combustion agent (agents) in form of solution or suspension solid at working temperature and pressure.

EFFECT: increased heat emission per unit of weight of oxidant or mixture; increased density of liquid fuel, improved combustion of hard ignited ingredients.

4 cl, 5 ex

Description

The invention relates to fuel for jet engines (WRE) and for liquid rocket engines (LRE).

Various types of fuel and fuel additives are known (see US Pat. No. 2205863). However, to achieve maximum engine thrust, the fuel for the WFD must satisfy the maximum heat release condition not in the usual sense - per unit mass of fuel (implied with free access of air), but per unit mass of oxidizer spent on burning this fuel, since its amount in the working engine space is limited. And for a rocket engine, fuel should give maximum heat per unit mass of the “fuel-oxidizer” mixture. Some of these known, as well as open in the future, combustible substances can be in solid working conditions (operating conditions hereinafter mean the temperature and pressure at which the fuel is stored in the aircraft, transported to the engine, and fed to the combustion chamber )

In order to be able to use these solids as fuel for the WFD and LRE, they should be dissolved in a suitable combustible substance that also has good heat dissipation and is liquid under operating conditions, or in a mixture of such substances.

In addition, in aircraft and rockets, the density of the fuel also matters, since the volume and weight of the tanks depend on this. The dissolution of a solid substance, which, as a rule, has a higher density will also increase the density of the resulting fuel.

Moreover, some substances that could be used as fuel have difficult ignition, since they require preheating (for example, ammonia). The dissolution in such a liquid fuel (in particular, liquid ammonia) of other combustible substances having a lower temperature of the onset of the combustion reaction will allow the efficient burning of such "hardly flammable" fuels.

So, in order to increase the heat release per unit mass of the oxidizing agent or mixture, in order to increase the density of liquid fuel, and also to improve the combustion of refractory ingredients, liquid fuel containing an ingredient that is liquid under operating conditions additionally contains a substance (s) in the form of a solution or suspension, solid under operating conditions.

It is possible to facilitate the ignition of hardly flammable substances in a gaseous state by adding one or more gaseous ingredients. That is, a fuel containing a flammable ingredient gaseous under operating conditions further comprises one or more flammable ingredients in a gaseous state.

And it is possible to facilitate the ignition of hardly flammable substances that are in working conditions in a liquid state by adding one or more solid (in the form of a solution or suspension) or liquid (in the form of a solution or emulsion) ingredients. That is, a fuel containing a flammable ingredient that is liquid under operating conditions, additionally contain one or more flammable ingredients in the form of a solution, suspension or emulsion.

Of course, a combination of additives is also possible. For example, hardly flammable liquid fuel may contain both soluble and insoluble liquid and solid additives (ingredients).

Example 1. Among non-toxic substances, hydrogen has the best per unit mass of oxygen and per unit mass of the mixture (rocket fuel). But its use in the WFD and LRE requires large volumes of tanks and low cryogenic temperatures. Among non-toxic and inexpensive substances, acetylene has good heat dissipation, moreover, it has a higher combustion temperature. However, its use is difficult due to the peculiarities of its phase transition: upon cooling, it passes into the solid state (at -84.1 ° С).

In order to use acetylene in the WFD and LRE, solid acetylene should be dissolved in liquid ethylene, ethane, nitroethylene, nitroethane, 1-nitropropane, 2-nitrobutane or a mixture thereof.

Example 2. Good heat dissipation per unit mass of the oxidizing agent may be possessed by substances having a low heat of combustion per unit mass of its own, for example, urotropin. To feed it into the combustion chamber, it should be dissolved in heptyl alcohol, hydrazine, or in another suitable solvent, which may possibly be liquefied gases, such as ammonia (there is no data on the solubility of urotropine in ammonia).

Example 3. A common fuel for the WFD and LRE is kerosene. Trinitro-m-xylene can be dissolved in kerosene to increase the fuel density.

Example 4. Ammonia as fuel is hardly flammable and does not burn in air. This is due to the peculiarities of the equilibrium decomposition of ammonia into hydrogen and nitrogen: the endothermic reaction and the desired equilibrium are achieved at low pressures and high temperatures. To create the necessary conditions in gaseous ammonia, a combustible gas (s) should be dissolved, preferably with a high combustion temperature. For example, acetylene or acetylene mixed with ethylene (see example 1).

Example 5. If the supply of ammonia to the combustion chamber is carried out in a liquid state, then a liquid or solid combustible ingredient, for example indole, dissolved in it, can be added to liquid ammonia. The solubility of substances in liquid ammonia is not well understood, but it is possible to dissolve liquid hydrocarbons, such as propane, or solid organic substances, such as trinitro-m-xylene.

Combustible combustible in examples 1-3 almost simultaneously. In examples 4 and 5, combustible ingredients are burned out in stages: first, a flammable ingredient, then a self-sustaining decomposition and combustion reaction of ammonia begins, and then the resulting hydrogen is burned.

In examples 2, 3, 5, non-optimal additive ingredients were used, since there is no extensive reference data on heat release per unit mass of the oxidizing agent or mixture, and the mutual solubility of various substances has not been adequately studied. Necessary calculations and experiments are required.

The value of inventions is not limited to their current use. The appearance of new substances synthesized specifically for this purpose may give the invention particular relevance in the future.

Claims (4)

1. Fuel containing a liquid at operating temperatures and pressures, the ingredient and characterized in that it additionally contains in the form of a solution or suspension of a combustible substance (s), solid at operating temperatures and pressures. 2. The fuel according to claim 1, characterized in that it is a solution of solid chilled acetylene in liquid chilled ethylene, ethane, nitroethylene, nitroethane, 1-nitropropane, 2-nitrobutane or a mixture thereof. 3. The fuel according to claim 1, characterized in that it is a solution of urotropine in heptyl alcohol or hydrazine. 4. Fuel according to claim 1, characterized in that it is a solution of trinitro-m-xylene in kerosene.