CN1186605C - Pressure measuring method for energetic material DDT pipe experiment - Google Patents

Abstract

The present invention relates to a pressure measuring method for an energetic material DDT pipe experiment. In the pressure measuring method for an energetic material DDT pipe experiment, an inertia block having similar shock impedance with a measured energetic material is embedded into an unburned and unexploded area of a DDT pipe, and one or a plurality of compound Lagrangian sensors are embedded into the inertia block. Each compound Lagrangian sensor is composed of a manganin pressure-resistance meter and a constantan stretching meter. The pressure measuring method for an energetic material DDT pipe experiment can obtain one or a plurality of pressure waveforms, and therefore, the pressure measuring method for an energetic material DDT pipe experiment provides new experimental data for researching and controlling the DDT phenomenon of the energetic material. The present invention has the advantages of real measuring condition, complete measuring process, precise, comprehensive and reliable measuring data, etc.

Description

The pressure measurement method of energetic material DDT pipe experiment

Technical field: the present invention is a kind of dynamic pressure waveform measuring method, and the dynamic pressure waveform that particularly relates to the experiment of energetic material DDT pipe is measured.

Background technology: when the security performance of energetic material (mainly being meant explosive and propellant) was measured and estimated, its COMBUSTION TO DETONATION TRANSITION (DDT) performance was an important indicator.Energetic material DDT performance measurement is to carry out in the metal tube of specific dimensions, is referred to as the experiment of DDT pipe.Because the DDT process is very complicated physics, chemistry and a mechanical process, its burning rate centimetre develops into the thousands of rice of per second by the per second number, corresponding pressure increases to a hundreds of thousands atmospheric pressure from several atmospheric pressure, and laminar flow, forced convection shock wave three phases have then been experienced in particle movement.Pressure waveform problems of measurement for DDT pipe experimentation never solves, and its difficulty is:

If sensor is too thick too big, then will change the actual measurement state; If sensor is too thin too little, then writing time too short, can not finish the measurement of overall process, and the complex flow state in the DDT pipe and high temperature, high pressure conditions will make the very fast inefficacy of general pressure transducer.Therefore the experiment of DDT pipe generally all is by reclaiming the DDT pipe, by similar experiment relatively, drawing the dangerous parameter of qualitative with relative DDT.At present to the mechanism research of DDT phenomenon, to the DDT phenomenon controlled and the demand utilized all an urgent demand test the change curve of the pressure waveform that the DDT process can be provided.

Summary of the invention: technical matters to be solved by this invention provides and a kind ofly measures that state is true, measuring process fully, the measurement data pressure measurement method of energetic material DDT pipe experiment accurately and reliably.

The pressure measurement method of energetic material DDT pipe of the present invention experiment, it is characterized in that the inert block identical with the measured energy material impact impedance imbedded in the unburned and unexploded area of DDT pipe, imbed compound Lagrangian sensor in the inert block, every group of compound Lagrangian sensor imbedding in the inert block is made up of a manganese-copper piezoresistance meter and a constantan tension gage, both have identical geometric configuration, and in experiment, be on the position of symmetry, comprise pressure signal and stretch signal Δ R (t) in the tracer signal of manganese-copper piezoresistance meter _m, and only contain stretch signal Δ R (t) in the tracer signal of constantan tension gage _c, utilize following formula that experimental result is handled and obtain pressure waveform signal,

P(t)＝α*ΔR(t) (1)

$\mathrm{\ΔR}\left(t\right)=\frac{{\mathrm{\ΔR}\left(t\right)}_m}{R_{m0}}-\frac{K_m}{K_c}*\frac{{\mathrm{\ΔR}\left(t\right)}_c}{R_{\mathrm{co}}}---\left(2\right)$

α wherein: be the piezoresistance coefficient of manganese-copper piezoresistance meter 5;

K _m, K _c: the drawing coefficient that is respectively manganese-copper piezoresistance meter 5 and constantan tension gage 6;

R _M0, R _Co: the base voltage signal that is respectively manganese-copper piezoresistance meter 5 and constantan tension gage 6.

As further scheme of the present invention, the described compound Lagrangian sensor of imbedding inert block is one or more groups.

Utilize measuring method of the present invention, both reduced the change (because inert block with the impact impedance of the energetic material of unburned and unexploded area identical) of embedded-type sensor, solved not long problem of sensor record time again measuring state.The many groups pressure waveforms that utilize the compound Lagrangian sensor of many groups to record can cause position, blowback intensity of wave and speed thereof etc. and make quantitative analysis the formation of pressure in COMBUSTION TO DETONATION TRANSITION (DDT) process, its rise speed and velocity of propagation, detonation.Be the further mechanism of research DDT phenomenon, and control and utilize it, new experimental data is provided.Have advantages such as the measurement state is true, measuring process is complete, measurement data is accurate, comprehensive, reliable.

Description of drawings:

Fig. 1 is the pressure measurement method experimental provision structural representation of energetic material DDT pipe of the present invention experiment.

Fig. 2 is the A-A profile of Fig. 1.

Fig. 3 is the oscillograph recording signal graph of manganese-copper piezoresistance meter.

Fig. 4 is the oscillograph recording signal graph of constantan tension gage.

Embodiment:

Realize that step of the present invention is as follows: in the experiment of energetic material DDT pipe (as shown in Figure 1, 2), imbed the inert block 3 close with this energetic material impact impedance at the unburned and unexploded area 2 of metal tube 1, the length of inert block 3 is less than 1/3rd of unburned and unexploded area length.In distance inert block 3, imbed one or more groups compound Lagrangian sensor 4.Every group of compound Lagrangian sensor is made up of a manganese-copper piezoresistance meter 5 and a constantan tension gage 6, and both have identical geometric configuration, and is in experiment on the position of symmetry.Comprise pressure signal and stretch signal Δ R (t) in the tracer signal of manganese-copper piezoresistance meter 5 _m(as shown in Figure 3).And only contain stretch signal Δ R (t) in the tracer signal of constantan tension gage 6 _c(as shown in Figure 4).Utilize following formula that experimental result is handled and to obtain pressure waveform signal.

P(t)＝α*ΔR(t) (1)

$\mathrm{\ΔR}\left(t\right)=\frac{{\mathrm{\ΔR}\left(t\right)}_m}{R_{m0}}-\frac{K_m}{K_c}*\frac{{\mathrm{\ΔR}\left(t\right)}_c}{R_{\mathrm{co}}}---\left(2\right)$

α wherein: be the piezoresistance coefficient of manganese-copper piezoresistance meter 5;

K _m, K _c: the drawing coefficient that is respectively manganese-copper piezoresistance meter 5 and constantan tension gage 6;

R _M0, R _Co: the base voltage signal that is respectively manganese-copper piezoresistance meter 5 and constantan tension gage 6.

Claims (2)

1, the pressure measurement method of a kind of energetic material DDT pipe experiment, it is characterized in that the inert block identical with the measured energy material impact impedance imbedded in the unburned and unexploded area of DDT pipe, imbed compound Lagrangian sensor in the inert block, every group of compound Lagrangian sensor imbedding in the inert block is made up of a manganese-copper piezoresistance meter and a constantan tension gage, both have identical geometric configuration, and in experiment, be on the position of symmetry, comprise pressure signal and stretch signal Δ R (t) in the tracer signal of manganese-copper piezoresistance meter _m, and only contain stretch signal Δ R (t) in the tracer signal of constantan tension gage _c, utilize following formula that experimental result is handled and obtain pressure waveform signal,

P(t)＝α*ΔR(t) (1)

$\mathrm{\ΔR}\left(t\right)=\frac{\mathrm{\ΔR}{\left(t\right)}_m}{R_{m0}}-\frac{K_m}{K_c}*\frac{{\mathrm{\ΔR}\left(t\right)}_c}{R_{c0}}---\left(2\right)$

α wherein: be the piezoresistance coefficient of manganese-copper piezoresistance meter 5;

K _m, K _c: the drawing coefficient that is respectively manganese-copper piezoresistance meter 5 and constantan tension gage 6;

R _M0, R _Co: the base voltage signal that is respectively manganese-copper piezoresistance meter 5 and constantan tension gage 6.

2,, it is characterized in that the compound Lagrangian sensor of imbedding inert block is one or more groups by the pressure measurement method of the described energetic material DDT pipe of claim 1 experiment.

Images