FI107296B - Apparatus for measuring the rate of burning of a propellant - Google Patents

Description

j 107296

Device for measuring propellant burning rate

Separated by division 970272 of January 23, 1997, Part 4/4.

The present invention relates to a measuring device for measuring the burning rate of solid or liquid propellants or other propellants. to determine the pressure dependence of the burn rate.

Rocket and other propellant fire rates are measured by making the propellant rod, which is burned in a pressure vessel at constant pressure, usually a few tens of bars. Multiple burns are performed at different constant pressures and the propellant fire rate is measured separately at each pressure. The results are fitted to a suitable fire equation such as the Vieille equation r = ap + b or the exponential equation r = apn (more commonly used with rocket propellants) (a = experimental constant, b = experimental constant, n = pressure exponent; experimental value, r = fire rate, p = pressure ). The equation can be used to calculate the correct weapon charge or the relationship between rocket chamber pressure and angular diameter.

The propellant rod fire rate can be measured in many different ways. The oldest method (B.L.

Crawford, C. Hugett, F. Daniels, and R. E. Wilfong, Ami Chem. 19,630 (1947)) is to use measuring *.:.: Yarns that burn across as the fire progresses to the measuring thread. Cross burns 20 ...; is expressed electronically and the distance between the wires and the time intervals between the burns is calculated by the fire ««:.:: peus. The method is still used for its reliability.

. A disadvantage of the above-mentioned gauge method is that the driving charge is easily twisted or skewed. ·: ·. j ° Pa is interrupted by the tension of the measuring wires or that the wiring applied to the measuring wires does not withstand the heat caused by the running charge. In order to facilitate the use of the measuring thread method and to eliminate the aforementioned stresses, the connecting rails of the measuring threads of the device according to the invention are shaped according to claim 1. For example, the ground rail may have the shape of grooves of punctures opposite to the other attachment points of the measuring rods with respect to the propellant rod.

• c *. 30 Other types of tension - free mounts are also possible. At the same time, • · c: ... * improves the usability of the device by making it easier to install measuring rods.

··· ·: "Figure 1 shows an example of the design of the coupling rails, Figure 1 shows a side and top diagram of the pressure vessel end. · Measuring wires (Figure 1, point 1) mounted on the pressure vessel lid (Figure 1, item 1) 3) do not twist the drive charge if the wires are attached as shown in Figure 1. The ground rail (Figure 1, Item 2) is shaped such that the wires always run perpendicularly through or around the propeller rod when the other end is attached to the measuring rails (Figure 1, Item 4).

2 107296

Figure 2 is a diagram of the hardware. The apparatus consists of a pressure vessel (Figure 2, item 4) with a guide (Figure 2, item 7) enclosed. If desired, the vessel is filled with liquid (Fig. 2, item 6) or the driving charge is otherwise inhibited so that it does not burn at any place other than the ignited end. The pressure was limited by a back-up valve (Figure 2, item 1), which can simultaneously function as a gas fill valve and a Drain Emptying Valve. The propellant is attached to the holder (Figure 2, item 8). The apparatus also includes a pressure sensor or gauge to measure the pressure in the vessel. (Figure 2, item 3). Further, the apparatus includes a system for igniting propellant, e.g., a filament (Figure 2, item 5) and ignition wires passed through a cover (Figure 2, item 2).

The foregoing examples are in no way intended to limit the invention to examples t t 10 derived therefrom. Many, not to mention, modifications of the invention are possible within the scope of the inventive ideas defined in the following claims: 1 · 20 • 1 · · · · 25 · · · · · · · · · · · · · · · · · · · · · · · · «• · · • • • • • ee •« · • · 30 · ·

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Claims (3)

3 107296 Claim 5 Apparatus for measuring the rate of combustion of propellant, characterized in that, at one end of the pressure vessel, ignited propellant (Fig. 1, point 3) is provided with a ground wire (Fig. 1, point 3) 2) is shaped as a groove of points opposite the other anchorage points of the measuring wires with respect to the propellant (Figure 1, item 4). 10 1. Apparat för att rotten drivmedlets förbränningshastighet, kånetecknad av, att i drivmedlet (Bild 1, point 1), som antänds och brinner i et tryckkärl frän ena änden, Bäst mät-ningsträdar (Bild 1, point 3), som registererar fortplantningen av förbränningsfronten electro-risk genome att tran avbränns och kännetecknad av, att mätningsträdam (picture 1, point 2) formats som en bana av punkter, som ligger mittemot de • · »· • j ': andra fastpunktema för mätningsträdama (Bild 1, point 4). • «· · • 20» · · ♦ 1 · • ♦ · «ti ··· • · ♦ · ·« 25 · ♦ · • • 25 · ♦ * 25 ♦ ♦ ♦ · • · · · ♦ • »» · · 30 ♦ • «« «·