JPH0447217B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a starting device for a metal combustor such as an alkali metal, and more specifically, to a starting device for starting combustion in a metal combustor that causes an exothermic reaction between a metal and an oxidizing agent, and particularly for use in underwater vehicles etc. The present invention relates to a starting device for a metal combustor used in a steam generator suitable as a power source. Traditionally, metal combustors have been used for a variety of applications. The present invention aims to suitably apply the principle of this metal combustor to a steam generator that is a power source for an underwater vehicle. In general, a closed system is considered effective as a propulsion power generation device for underwater vehicles, which are becoming deeper and more powerful. It requires a lot of fuel. By the way, alkali metals (for example, lithium; Li) are attracting attention as such fuels, and by adding an oxidizing agent (for example, sulfur hexafluoride; SF ₆ ) to these metals, the following reaction can be obtained. 8Li＋SF ₆ →Li ₂ S＋6LiF ＋3.6KWHr／Kg
(per unit weight of Li and SF ₆ ) A metal combustor that performs such a reaction needs to melt the alkali metal in a short time (on the order of a few seconds) when starting combustion. This is because in a solid state, it hardly reacts with oxidizing agents. Furthermore, due to the special circumstances of being used for underwater vehicles, there are various restrictions, and there is a need for a starting device for melting and heating the alkali metal that satisfies these restrictions. Moreover, this starter device also serves as an aid to metal combustion, a reaction that has a relatively slow response, and also has the purpose of greatly contributing to the rapid increase in output of the power generator in its initial stage. The present invention has been made in order to provide a starting device for melting and heating the above-mentioned alkali metals. That is, the present invention provides a starter device to be loaded into a columnar space of a metal combustor, in which AI, etc. A pellet-like base material containing metal powder and a perchlorate such as KC10 ₄ preferably in a theoretical equivalent ratio, and a metal powder containing the same components as the base material, finer than the base material, and molded with a lower squeezing force than the base material. A small-diameter combustion improver, a powdered ignition agent for igniting the combustion improver, and an electric ignition part are sequentially loaded, the lid is covered with a holder, and the electric ignition part is connected to an ignition ball routed into the ignition agent This is a starting device for a metal combustor, characterized in that an ignition wire is connected to the metal combustor, and the ignition wire is drawn out through the holder. The present invention has the following advantages. (1) Melting and heating alkali metals in a short period of time (on the order of a few seconds). That is, it has a high energy density, a fast reaction, and good heat transfer to the alkali metal. (2) No moisture is generated during the reaction. (3) The base agent and combustion aid have low hygroscopicity. Therefore, manufacturing is easy, and storage and handling are also easy. (4) The volume of the main agent and combustion aid can be reduced by squeezing, and the burning rate can be controlled by the degree of squeezing. (5) No danger. (This type of reaction is explosive due to severe impact, but it can be made less sensitive than ordinary gunpowder by adjusting the particle size of the raw materials.) (6) It is lightweight and compact. Furthermore, since the metal combustor is hermetically sealed, gas generation is minimal, and heat loss due to gas generation itself is minimal. According to the present invention, such a metal combustor can be suitably used as a power source for an underwater vehicle. FIG. 1 is a diagram showing an embodiment of the starting device of the present invention. In Figure 1, 3 is the main agent for melting and heating the alkali metal, which is made by blending Al and KClO ₄ in a theoretical equivalent ratio and forming it into pellets with a small amount of binder.The particle size of Al can be adjusted according to the required performance. Decide the degree of compression. Reference numeral 2 is a combustion improver which is added in a small amount for the purpose of promoting ignition and combustion of the main agent 3, and makes the size of the pellet smaller than that of the main agent. In some cases, the particle size of Al is finer than that of the base Al, and the degree of compression is also lowered. As a result, the volumetric efficiency deteriorates somewhat, but
It is effective for the purpose mentioned above. The main agent 3 is ignited using an ignition agent 4 made of gas-free metal powder, metal oxide, etc., and an ignition ball 5, which are fixed with a holder 7. The ignition ball 5 is ignited through an ignition line 6. A combustion improver 2, a main agent 3, an ignition agent 4, an ignition ball 5, an ignition wire 6, and a holder 7 are wrapped in a wire mesh or the like 1 to form one starting device. The combination of Al powder and the oxidizing agent KClO ₄
Among the combinations of powder and other oxidizing agents, it has the third highest energy density per weight (2400kcal/Kg), has low hygroscopicity, and does not generate gas. By using this as a base agent and a combustion aid, alkali metals can be easily melted and heated. However, according to the method used here, lithium metal in a completely sealed metal combustor must be melted and heated instantaneously (on the order of several seconds). Al and
In the KClO ₄ combination, the combustion temperature reaches 3500 °C, which will temporarily generate high-pressure gas without rapid cooling. Therefore, in the present invention, the combustion speed is controlled by changing the size of the pellet, the degree of compression, and the grain size of the Al, and the entire pellet is wrapped with a wire mesh, etc. to improve the heat transfer to the alkali metal. It is something. Example Using 300 g of Li as the alkali metal, the metal combustor shown in Figure 2 A and B was prepared with the following specifications. Note that FIG. 2A is a sectional view, and FIG. 2B is an external view, and A and B in FIGS. 2A and 2B indicate thermocouples.

[Table] When ignited with the above specifications, Li melted within 3 seconds after ignition, as shown in Figure 3.
Heating was possible, and the pressure increase was only 6.5 Kg/cm ² at the peak pressure. In addition, A in Figure 3
indicates the temperature change measured by thermocouple A, and B indicates the temperature change measured by thermocouple B.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing an example of an embodiment of the starting device of the present invention, Fig. 2 A and B are diagrams showing a metal combustor prepared in an embodiment of the present invention, and Fig. 3 is a diagram showing a metal combustor prepared in Example 1 of the present invention. It is a chart showing the obtained results.

Claims (1)

[Claims] 1. In a starting device to be loaded into a columnar space of a metal combustor, a cylindrical container made of a porous material contains a pellet-like base material whose main components are metal powder and perchlorate, and components similar to the base material, A small-diameter combustion improver made of metal powder finer than the main material and molded with a compression force lower than that of the main material, a powdered ignition agent containing the same components as the main material, and an electric ignition part were sequentially loaded, and the lid was covered with a holder. A starting device for a metal combustor, characterized by: