CN104180926A - Jet-flow reflection temperature field testing method - Google Patents

Abstract

A jet-flow reflection temperature field testing method belongs to the field of research on flow of high-temperature high-speed fluids, and is applied to high-temperature high-speed jet flow. The method is characterized by comprising the steps of 1) preparing test equipment; 2) starting test when a system clock is synchronized with a jet flow generator; 3) processing data; and 4) implementing analysis and calculation. The method has the advantages that the amount of testing points, test data bulk and the number of test vehicles are decreased to a bearable scope of outfield; the ground of the outfield is not damaged, it is ensured that test targets are stable, and influence of outfield condensation and high-temperature on plastic pressure testing pipes are avoided; massive real-time high-frequency dynamic sampling data is collected in multiple channels and stored in a time-delay manner, the problems that the bandwidth and speed of a data collection and storage system are not high enough are solved, the data precision is solved, the operation frequency of jet flowing device is reduced, and the test cost is saved; the problem that test data is in one to one correspondence with jet flow state is solved; and a set of data collecting, processing and analyzing methods is thus established.

Description

A kind of jet flow reflected temperature field method of testing

Technical field

The invention belongs to the mobile research field of high temperature and high speed fluid, be specifically related to a kind of high temperature and high speed jet flow reflected temperature field method of testing.

Background technology

Jet vane in rocket, vectored thrust engine two-dimensional nozzle, acetylene flame welding, smelting iron and steel, all can run into the reflection problems of high temperature, high pressure, high speed jet in the processes such as dry-chemical extinguisher jeting effect research.Study on Test Method to high temperature and high speed reflection flow field has certain reference significance to the research of these problems.

Summary of the invention

The object of the invention is: solution high temperature and high speed jet flow runs into baffle plate and produces the test problem of jet flow reflected temperature field.

Technical scheme of the present invention is:

A kind of jet flow reflected temperature field method of testing, is characterized in that, comprises the steps:

First, setup test equipment: first set baffle plate, baffle plate is square, the length of side is 5～10 times of jet size D, and the angle on ground is between 45 °～90 °, air jet system spout axis is 3～5 times of nozzle diameter D to the distance on ground, and spout is 2D～3D to the distance of baffle plate, and survey rake is placed under spout, probe orientation is just to contrajet, first rake, apart from baffle plate 3D～5D, surveyed rake probe concordant with spout trailing edge, and second and third is surveyed rake and equidistantly arranges by 2.5D.Rearward extend to enough distances (approximately 20 meters) through steel pipe and extend to again temperature transmitter to side and be connected by testing apparatuss such as data collecting card and computing machines surveying pressure catheter boundling that rake connects.The steel pipe of guardwire bundle is wrapped with asbestos cloth;

Second, with after jet flow generating means synchro system clock, start test: whole fluctuations in discharge scope is divided into 4 ladders, increase gradually from small to large jet flow flow, stable maintenance one minute while reaching each test traffic ladder, flow reaches maximum rating and keeps reducing gradually flow after 1 minute, test again one time by contrary flow ladder order, close jet flow equipment;

The 3rd, data processing: thermopair can be measured the temperature range of 0 DEG C～1000 DEG C, the output current of corresponding temperature transmitter is 4～20mA, corresponding voltage table reading is 1000mV～5000mV.Temperature thermocouple all passes through demarcation, just can calculate according to calibration formula the temperature at probe place by recording the magnitude of voltage at thermopair two ends.Computing formula is T=0.25 (V-1000), and in formula, voltage V unit is mV;

The 4th, analytical calculation: can process out respectively temperature level, direction with jet flow intensity, height and from the variation rule curve of baffle plate distance and survey rake cross section flow parameter cloud atlas and provide various analyses to use overhead according to the data that record.

Described soil is surveyed the design processing of rake: native font is surveyed rake and is made up of two horizontal one perpendicular poles, whole support is connected on subplate bearer, whole survey rake fixed placement is on ground, two cross support arm length equal engine jet pipe diameter D, on it, arrange respectively 3 measuring points, each one of two ends and centre, montant Length Ratio jet pipe is slightly short to floor level, 6 measuring points are set on it, except arranging a measuring point with two cross bar point of crossing are each, 3 measuring points are set between two cross bars, one measuring point is set on the cross bar of top, measuring point spacing is more intensive below, about 0.2D, top measuring point spacing is more bigger, about 0.4D,

Advantage of the present invention is:

1) calculate the auxiliary stress test scope of delimiting of optimizing by CFD, optimize test erect-position and every and survey the rake measuring point distribution design processing font of being unearthed and survey rake, make measuring point quantity and amount of test data and test train number be reduced to the scope that outfield can be born;

2) design working flat plate base, tear the means such as calotte, pipeline parcel asbestos cloth open conveniently and accomplished neither to destroy outer Ground to ensure again to survey rake firm, solution outfield condensation and the impact of high temperature on plastics piezometric tube;

3) the real-time high frequency dynamic sampling of magnanimity data are taked to multichannel collecting time delay unloading method, solve data acquisition storage system bandwidth and the inadequate problem of speed, improve data precision simultaneously, reduce jet apparatus driving number of times, save testing expense;

4) take system clock to solve test data and jet flow state correspondence problem one by one with footwork;

5) a complete set of testing apparatus has been processed in design, has set up a set of data sampling and processing and analytical approach.

Brief description of the drawings

Fig. 1 test macro block diagram

Fig. 2 jet flow reflection schematic diagram

Fig. 3 optimizes rear survey rake and arranges erect-position schematic diagram

Fig. 4 optimizes rear survey rake measuring point arrangenent diagram

Fig. 5 power-on condition schematic diagram

Fig. 6 velocity flow profile schematic diagram

Embodiment

Below in conjunction with accompanying drawing and aeromotor jet flow reflection measurement case study on implementation, the present invention will be further described:

Referring to Fig. 1, is the theory diagram of this test macro.Velocity field test macro is made up of three groups of five-hole probes, scanning valve and data acquisition, register system.Every group of temperature probe is arranged on native font test rake support by the position designing.

Referring to Fig. 2, is 60 ° of jet flow reflection schematic diagram under baffle plate.3 × 6 meters of deflector sizes in test, become 60 ° with ground, with 75 ° of plane of symmetry angles.

Refer to Fig. 3, after optimizing, survey rake and arrange erect-position schematic diagram.Baffle plate not only has certain angle with ground, also with plane of symmetry deflection certain angle.Arrange as shown in the figure, left side air intake duct refluxes more serious, surveys rake be accordingly arranged according to certain rules from back to front jet pipe below, left side by three, and first rake is placed under spout, apart from 2.5 meters, baffle plate, and 2 meters of first, second and third rake spacing.

Refer to Fig. 4, after optimizing, survey rake measuring point arrangenent diagram.In figure, be to survey rake for the native font of testing requirement design processing, two cross bar length are D, 3 measuring points of each layout on it, and the list after optimization props up and surveys the upper measuring point quantity of rake is 10 measuring points.

Refer to Fig. 5, power-on condition schematic diagram.Whole engine fluctuations in discharge scope is divided into slow train, throttling, centre, maximum 4 ladders, open the throttle gradually from small to large and increase jet cutting car flow flow, stable maintenance one minute while reaching each test mode ladder, flow reaches maximum rating and keeps reducing gradually throttle after 1 minute, tests one time by contrary flow ladder order again.

Refer to Fig. 6, velocity flow profile schematic diagram.Visible in figure, near erect-position 1 place's reflection jet flow temperature deflector is higher, more weak more forward, obviously reduces near temperature rise auxiliary inlet door.

Claims (1)

1. a jet flow reflected temperature field method of testing, is characterized in that, comprises the steps:

First, setup test equipment: first set baffle plate, baffle plate is square, the length of side is 5～10 times of jet size D, and the angle on ground is between 45 °～90 °, air jet system spout axis is 3～5 times of nozzle diameter D to the distance on ground, and spout is 2D～3D to the distance of baffle plate, and survey rake is placed under spout, probe orientation is just to contrajet, first rake, apart from baffle plate 3D～5D, surveyed rake probe concordant with spout trailing edge, and second and third is surveyed rake and equidistantly arranges by 2.5D.Rearward extend to enough distances (approximately 20 meters) through steel pipe and extend to again temperature transmitter to side and be connected by testing apparatuss such as data collecting card and computing machines surveying pressure catheter boundling that rake connects.The steel pipe of guardwire bundle is wrapped with asbestos cloth;

Second, with after jet flow generating means synchro system clock, start test: whole fluctuations in discharge scope is divided into 4 ladders, increase gradually from small to large jet flow flow, stable maintenance one minute while reaching each test traffic ladder, flow reaches maximum rating and keeps reducing gradually flow after 1 minute, test again one time by contrary flow ladder order, close jet flow equipment;

The 3rd, data processing: thermopair can be measured the temperature range of 0 DEG C～1000 DEG C, the output current of corresponding temperature transmitter is 4～20mA, corresponding voltage table reading is 1000mV～5000mV.Temperature thermocouple all passes through demarcation, just can calculate according to calibration formula the temperature at probe place by recording the magnitude of voltage at thermopair two ends.Computing formula is T=0.25 (V-1000), and in formula, voltage V unit is mV;

The 4th, analytical calculation: can process out respectively temperature level, direction with jet flow intensity, height and from the variation rule curve of baffle plate distance and survey rake cross section flow parameter cloud atlas and provide various analyses to use overhead according to the data that record.