CN105974049A - Apparatus and method for measuring instantaneous burning rate of solid propellant - Google Patents

Abstract

The invention discloses an apparatus and method for measuring instantaneous burning rate of solid propellant. The apparatus comprises a sealed combustor, the combustor is internally provided with a weighing apparatus for placing a propellant sample to be measured, the weighing apparatus is connected to a data acquisition system in data connection, and the combustor is also connected to a pressure control apparatus which is used for controlling the pressure in a combustor chamber and an ignition device for igniting the propellant sample; the weighing apparatus is used for obtaining real time mass of the propellant sample; the data acquisition system is used for receiving real time mass information sent from the weighing apparatus, and calculating the instantaneous burning rate of the propellant sample according to the real time mass information. The apparatus and method solve the problems that instantaneous change of the burning rate cannot be measured in a condition with pressure oscillation and the like in the prior art, and high measurement precision is guaranteed.

Description

A kind of device measuring solid propellant instantaneous combustion speed and measuring method

Technical field

The invention belongs to Solid Rocket Motor Technology field, relate to a kind of measurement instantaneous combustion of solid propellant The device of speed and measuring method.

Background technology

Measure the conventional method Plays motor method of solid propellant combustion rate, medicated strip method and target collimation method to obtain Combustion speed belong to the Average burning rate in two particular moments；Closed burner method and patent Although ZL201410647522.0 can obtain during measurement combustion speed the most in the same time, but can only be directed to Burning pressure situation about persistently rising measures, and both approaches is finally given is not homostasis Combustion speed corresponding under pressure, it is impossible to fire the transient change of speed under the conditions of measurement pressure vibration etc., the most not Belong to instantaneous combustion speed measuring method；Ultrasonic method can measure the transient change of combustion speed in real time, but its test is The capacity of resisting disturbance of system is poor, precision is relatively low, combustion speed resolving power is low, in order to ensure higher certainty of measurement Needing to use bigger sample thickness, cause sample dosage relatively big, therefore the experimental provision of the method is relative Complexity, experimental cost are higher.

Summary of the invention

It is an object of the invention to provide a kind of device measuring solid propellant instantaneous combustion speed and measuring method, To solve in prior art, it is impossible to fire the transient change of speed under the conditions of measurement pressure vibration etc., and ensure The problem of higher certainty of measurement.

The first technical scheme of the present invention is, a kind of dress measuring solid propellant instantaneous combustion speed Put, including the burner sealed, be provided with for placing propellant sample weighing device to be measured in burner, It is intrinsic pressure that weighing device data cube computation has data collecting system, burner to be also associated with for controlling combustor Powerful little pressure controls device and for lighting the firing device of propellant sample；

Weighing device, for obtaining the real-time quality of propellant sample；

Data collecting system, sends, from weighing device, the real-time quality information of coming for receiving, and according to reality Time quality information, calculate propellant sample instantaneous combustion speed.

Further, weighing device, including being fixed on the base of combustor inner bottom part, base is arranged Current vortex sensor, current vortex sensor data cube computation to data collecting system, base is additionally provided with use In place propellant sample cantilever beam, the unsettled top being positioned over current vortex sensor of propellant sample, Current vortex sensor, for measuring the deflection of cantilever beam.

Further, firing device is the laser instrument being arranged on outside burner, the Laser emission side of laser instrument Overlap to the axis direction of propellant sample, and burner outer wall offers the windowpane passed for laser Mouthful.

Further, glass window is germanite glass.

Further, laser instrument is co₂Laser instrument.

Further, each side and the bottom of propellant sample is painted with flame retarding material.

The first technical scheme of the present invention is, above-mentioned a kind of measurement solid propellant instantaneous combustion speed The measuring method of device, implement according to following steps:

Step 1, weighing device and data collecting system are demarcated, and calculate current vortex sensor Output voltage and the relational expression being weighed between propellant sample mass；

Step 2, propellant sample is positioned on the cantilever beam of burner internal, controls dress by pressure The pressure putting control burner internal is changed；

Step 3, open laser instrument and light propellant sample, will be collected by current vortex sensor simultaneously Real-time voltage is delivered to data collecting system, until burning terminates, data collecting system is according to receiving Voltage data, can calculate the combustion speed of propellant sample.

Further, propellant sample is uiform section.

Further, propellant sample fires speed method particularly includes:

Current vortex sensor is sent the real-time voltage data of coming, is converted to the quality of propellant sample at any time Between change m (t)；

Then the combustion speed of propellant sample 1 is r:

$r\left(t\right)=\frac{1}{\mathrm{\ρ}A}\frac{dm\left(t\right)}{dt}---(1-1),$

Wherein, m (t) is the original quality of propellant sample, and ρ is the density of propellant sample, and A is for pushing away Entering the cross-sectional area of agent sample, t is the time.

The invention has the beneficial effects as follows, make use of high-precision weighing technology, the mass change of propellant is turned Being changed to the micro-strain of cantilever beam, deflection is entered by recycling high frequency sound, high-precision current vortex sensor Row is measured, such that it is able to use little propellant sample can complete test, and is obtained in that propellant Instantaneous combustion speed, and measuring accuracy can reach 0.1%, it is achieved that to instantaneous combustion speed High-precision high-frequency rate Measurement.

Accompanying drawing explanation

Fig. 1 is the structural representation of a kind of device measuring solid propellant instantaneous combustion speed of the present invention；

When Fig. 2 is the quality in a kind of device embodiment measuring solid propellant instantaneous combustion speed of the present invention Half interval contour figure；

When Fig. 3 is the quality pair in a kind of device embodiment measuring solid propellant instantaneous combustion speed of the present invention Between first derivative figure；

Fig. 4 be the present invention a kind of measure solid propellant instantaneous combustion speed device embodiment in combustion speed-time Half interval contour figure.

In figure, 1, propellant sample, 2. burner, 3. laser instrument, 4. glass window, 5. pressure controls Device, 6. current vortex sensor, 7. cantilever beam, 8. base, 9. data collecting system.

Detailed description of the invention

The present invention is described in detail with detailed description of the invention below in conjunction with the accompanying drawings.

One, the invention provides a kind of device measuring solid propellant instantaneous combustion speed and measuring method, as Shown in Fig. 1, including the burner 2 sealed, it is provided with in burner 2 for placing and weigh propelling to be measured The weighing device of agent sample 1 mass, weighing device data cube computation has data acquisition to be 9, and burner 2 is also Connect and have for controlling the powerful little pressure control device 5 of burner 2 intraventricular pressure and for lighting propellant The firing device of sample 1.

Wherein, weighing device, including the base 8 being fixed on bottom burner 2 indoor, base 8 sets It is equipped with current vortex sensor 6, base 8 is provided with the cantilever beam 7 for placing propellant sample 1, The position of propellant sample 1 is positioned at the top of current vortex sensor 6, current vortex sensor 6, is used for surveying The deflection of amount cantilever beam 7.

Firing device is to be arranged on the laser instrument 3 outside burner 2, and usual laser instrument 3 is co₂Laser Device.The axis direction of the Laser emission direction propellant sample 1 of laser instrument 3 overlaps, and outside burner 2 Wall is positioned at laser and offers glass window 4 through position, and glass window 4 is usually germanite glass, because Germanite glass is good to the transmittance of this laser.

Each side of propellant sample 1 and coated on bottom side are brushed with the thinnest one layer fire proofing and ensure propellant Sample 1 is neutral burning when burning.The quality of fire proofing is the least, during propellant combustion not Change.

Two, present invention also offers a kind of device measuring solid propellant instantaneous combustion speed and measuring method Measuring method, implements according to following steps:

Step 1, first weighing device and data collecting system 9 are demarcated, and calculate current vortex and pass Corresponding relation formula between sensor 6 output voltage and propellant sample 1 mass being weighed, ties demarcation Fruit is input to data collecting system 9, makes data collecting system 9 can directly export the propellant being weighed The quality of sample 1.

Wherein, demarcation method particularly includes: " pressure transducer is quiet according to national military standard specification QJ28A-98 State property energy uncertainty calculation method " in the scaling method that is given to weighing device and data collecting system 9 Demarcating, after demarcation, between the output voltage and the quality that obtain, relational expression shape is such as: Y=kX+b, its Middle X is the output voltage of current vortex sensor 6, and Y is the quality of the propellant sample 1 being weighed, k It is the result of calibrated and calculated with b.

Step 2, propellant sample 1 is positioned on the cantilever beam 7 within described burner 2, wherein, Solid propellant is uiform section；Owing to remaining end face and side have been carried out cladding process, so propellant Sample 1 only top end face can burn.

Start pressure controls device 5, controls device 5 by pressure and controls the pressure within described burner 2 It is changed by force；This pressure change rule can be arbitrary, and the measurement purpose being based entirely on user is gone Controlling, no matter pressure is how to change to the present invention, can accurately measure the combustion speed change of propellant.

Propellant sample 1 lighted by step 3, unlatching laser instrument 3, makes laser pass through point after glass window 4 Combustion solid propellant sample 1, the real-time voltage conveying that simultaneously will be collected by described current vortex sensor 6 To data collecting system 9, until burning terminates, data collecting system 9 is according to the whole voltages received Data, can calculate the combustion speed of described propellant sample 1.

Wherein, data collecting system 9 calculates instantaneous combustion speed method particularly includes: data collecting system 9 will The voltage data sent by current vortex sensor 6, is converted to the change in time of the quality of propellant sample 1 Change m (t)；

Then the combustion speed of propellant sample 1 is r:

$r\left(t\right)=\frac{1}{\mathrm{\ρ}A}\frac{dm\left(t\right)}{dt}---(1-1),$

Wherein, m (t) is the original quality of propellant sample 1, and ρ is the density of propellant sample 1, A For the cross-sectional area of propellant sample 1, t is the time, ρ Yu A is all it is known that whereinCan utilize The correlation technique differentiated in numerical computation method.

Embodiment:

The present invention measures the dependency structure parameter of device of solid propellant instantaneous combustion speed and unit type such as Under:

(1) burner 2 material elects 30CrMnSi, external diameter 150mm, internal diameter 130mm, wall thickness as 10mm；

(2) model of current vortex sensor 6 selected by is development in science and technology company limited of Zhuzhou Air China ZA-21 Type, range is 0～2mm；

(3) stainless steel material that cantilever beam 7 uses is 1Cr18Ni9Ti, and a length of 100mm is a width of 10mm, thickness is 1mm；

(4) data collecting system 9 uses DEWESoft Sirius, and sample frequency is 5000Hz；

(5) the AP/HTPB composite propellant density used is 1700kg/m³, propellant cross-sectional area For A=4.47mm², a length of L=37.01mm；

(6) laser instrument 3 uses U.S. Synrad J48-5.

(7) utilize pressure to control device 5 and burner 2 is applied with the sinusoidal pressure that frequency is 1.5923Hz Hard oscillation.

Data Processing in Experiment process is as follows:

(1) before experiment being demarcated weighing device, original nominal data and calibrated and calculated result are as follows Shown in table.

Table 1 current vortex sensor nominal data

Table 2 current vortex sensor calibration result

By calibration result it can be seen that non-linear, the uncertainty of current vortex sensor and repeatability all exist About 0.1%.

(2) carried according to GJB97A-2001 " standard testing motor technology wants summed data to process " The method gone out, from the quality time curve chart of Fig. 2, reads propellant fire initial time t₀；With As a example by mass-time curve shown in Fig. 2, read and obtain propellant fire initial time t₀=0.37s, terminates Time t₁=7.8s.

(3) the quality time experimental data to propellant medicine, utilizes " three samples in numerical analysis Bar method of derivation " (class.htu.cn/shuzhifenxi/chapter4/No.4.htm) calculate Mass versus Time single order DerivativeResult is as shown in the first derivative figure of Fig. 3 Mass versus Time；

(4) according to combustion speed formula (1-1):Bond quality can to the first derivative figure of time Dynamically to be fired speed, as shown in the combustion speed-time plot of Fig. 4.

Prior art is all directly to measure the change of position, combustion face, and then calculates instantaneous combustion speed；Measure combustion The precision of the method for position, face all ratios are relatively low, and the most instantaneous combustion speed certainty of measurement also ratio is relatively low；Owing to measuring Method resolving power is relatively low, it is desirable to fires face change ratio during propellant combustion more significant, is easily caused sample Large usage quantity or temporal resolution are relatively low.

The present invention is to measure the transient change of propellant sample quality in combustion, make use of high accuracy Weighing technology, the mass change of propellant sample will be converted to the micro-strain of cantilever beam, recycling Deflection is measured by high frequency sound, high-precision current vortex sensor, it is only necessary to little propellant examination Sample, it is possible to measure the transient change of propellant mass in combustion process, it is achieved that instantaneous to propellant Combustion speed high accuracy, high-frequency measurement.

Claims (9)

1. the device measuring solid propellant instantaneous combustion speed, it is characterised in that include the burning sealed Device (2), is provided with for placing propellant sample (1) weighing device to be measured in described burner (2), Described weighing device data cube computation has data collecting system (9), described burner (2) to be also associated with using Control device (5) in controlling the powerful little pressure of burner (2) intraventricular pressure and be used for lighting propellant examination The firing device of sample (1)；

Described weighing device, is used for obtaining the real-time quality of described propellant sample (1)；

Described data collecting system (9), sends, from described weighing device, the real-time quality of coming for receiving Information, and according to real-time quality information, calculate the instantaneous combustion speed of described propellant sample (1).

A kind of device measuring solid propellant instantaneous combustion speed the most as claimed in claim 1, its feature exists In, described weighing device, including the base (8) being fixed on bottom described burner (2) indoor, institute State and current vortex sensor (6) is set on base (8), described current vortex sensor (6) data cube computation To described data collecting system (9), described base (8) is additionally provided with for placing described propellant The cantilever beam (7) of sample (1), described propellant sample (1) is unsettled is positioned over described current vortex biography The top of sensor (6), described current vortex sensor (6), it is used for measuring the deformation of cantilever beam (7) Amount.

A kind of device measuring solid propellant instantaneous combustion speed the most as claimed in claim 1 or 2, it is special Levying and be, described firing device is the laser instrument (3) being arranged on described burner (2) outward, described sharp The axis direction of propellant sample (1) described in the Laser emission direction of light device (3) overlaps, and described combustion Burner (2) outer wall offers the glass window (4) passed for described laser.

A kind of device measuring solid propellant instantaneous combustion speed the most as claimed in claim 1 or 2, it is special Levying and be, described glass window (4) is germanite glass.

A kind of device measuring solid propellant instantaneous combustion speed the most as claimed in claim 1 or 2, it is special Levying and be, described laser instrument (3) is co₂Laser instrument.

A kind of device measuring solid propellant instantaneous combustion speed the most as claimed in claim 1 or 2, it is special Levying and be, each side and the bottom of described propellant sample (1) are painted with flame retarding material.

7. the measurement of a kind of device measuring solid propellant instantaneous combustion speed as described in Claims 1-4 Method, it is characterised in that implement according to following steps:

Step 1, weighing device and data collecting system (9) are demarcated, and calculate current vortex sensing The output voltage of device (6) and the relational expression being weighed between propellant sample (1) quality；

Step 2, propellant sample (1) is positioned over the cantilever beam (7) that described burner (2) is internal On, the pressure controlling described burner (2) internal by pressure control device (5) is changed；

Propellant sample (1) is lighted in step 3, unlatching laser instrument (3), is passed by described current vortex simultaneously The real-time voltage collected is delivered to data collecting system (9) by sensor (6), until burning terminates, Described data collecting system (9), according to the voltage data received, can calculate the examination of described propellant The combustion speed of sample (1).

A kind of device measuring solid propellant instantaneous combustion speed the most as claimed in claim 7, its feature exists In, described propellant sample (1) is uiform section.

9. measuring method as claimed in claim 8, it is characterised in that data collecting system 9 calculates institute State propellant sample (1) combustion speed method particularly includes:

Described current vortex sensor (6) is sent the real-time voltage data of coming, is converted to described propellant The quality m (t) over time of sample (1)；

Then the combustion speed of propellant sample 1 is r:

$r\left(t\right)=\frac{1}{\mathrm{\ρ}A}\frac{dm\left(t\right)}{dt}---(1-1),$

Wherein, m (t) is the original quality of propellant sample (1), and ρ is the close of propellant sample (1) Degree, A is the cross-sectional area of propellant sample (1), and t is the time.