CN102692369A - Measuring device and measuring method for measuring axial steady state permeability of continuous fiber bundle - Google Patents

Abstract

The invention provides a measuring device and a measuring method for measuring the axial steady state permeability of a continuous fiber bundle. The device comprises a gas tank, a pressure valve, an injector, a plastic short tube and a fiber bundle clamping tube; the gas tank, the pressure valve, a three-way joint and the plastic short tube are sequentially connected in series in a sealed mode; a vertical port of the three-way joint is connected with the injector in a sealed mode; the other end of the plastic short tube is in interference fit with the fiber bundle clamping tube; liquid is stored in the injector; the fiber bundle is inserted in the fiber bundle clamping tube; and the fiber bundle clamping tube is a rigid impervious tube. A certain pressure is provided for measurement of the permeability of the fiber bundle by the gas tank; and the permeability of the fiber bundle is estimated by measuring the quality of liquid of the totally soaked fiber bundle, which outflows in a certain time.

Description

The measurement mechanism and the measuring method of the axial steady-state permeation rate of a kind of continuous tow

Technical field

The present invention relates to resin base fiber reinforced composite material liquid molding technical field, be specially the measurement mechanism and the measuring method of the axial steady-state permeation rate of a kind of continuous tow.

Background technology

Permeability is the parameter that characterizes fluid mobile complexity in porous medium under the pressure effect, and the resistance to flow of the big more expression porous medium of permeability convection cell is more little.Adopt RTM injection moulding or other liquid molding technology to strengthen in the process of preform to the injection continuous fiber along fiber axis, the axial dispersion rate is the key parameter of its flowing velocity of decision.

The axial dispersion rate is divided into axial steady-state permeation rate and axial transient state permeability.At present, the axial steady-state permeation rate of fibrous bundle is all measured in flat plate mold.This method is that fibrous bundle is put into flat plate mold and calculated the porosity of this fibre reinforcement, through the permeability of unidirectional injection experiment measuring fibrous bundle, representes the axial steady-state permeation rate of fibrous bundle under the certain porosity with this permeability.Because fibrous bundle lay in flat plate mold is uneven, especially at the die edge place, the porosity of fibre reinforcement is high, resin flows is fast, i.e. edge effect.Edge effect will cause measured permeability ratio actual value bigger than normal.

Summary of the invention

The technical matters that solves

For solving the problem that has edge effect in the prior art; The present invention proposes the measurement mechanism and the measuring method of the axial steady-state permeation rate of a kind of continuous tow, be used to measure under the different injection pressures permeability of different porosities fibrous bundle under permeability and the uniform pressure of equal porosity fibrous bundle.

Technical scheme

The present invention provides certain pressure for the fibrous bundle permeability survey through gas tank, and the liquid quality that the fibrous bundle after soaking into fully through measurement flows out within a certain period of time comes the permeability of compute fiber bundles.

Technical scheme of the present invention is:

The measurement mechanism of the axial steady-state permeation rate of said a kind of continuous tow is characterized in that: comprise gas tank, pressure valve, syringe, plastic tubulature and fibrous bundle pinch tube; The gas tank outlet pressure valve import that is tightly connected; The pressure valve exit seal connects the horizontal port of threeway, and horizontal port of another of threeway and plastic tubulature one end are tightly connected, and the vertical port and the syringe outlet of threeway are tightly connected; Be inserted with the fibrous bundle pinch tube in the plastic tubulature other end, and plastic tubulature and fibrous bundle pinch tube interference fit; Liquid storage is in syringe; Be inserted with fibrous bundle in the fibrous bundle pinch tube; The fibrous bundle pinch tube is the non-osmos tube of rigidity; The outlet of fibrous bundle pinch tube has the container that collects liquid.

The measurement mechanism of the axial steady-state permeation rate of said a kind of continuous tow is characterized in that: comprise rough grade pressure valve and high-precision pressure valve; Rough grade pressure valve and the series connection of high-precision pressure valve seal; The be tightly connected horizontal port of threeway of the gas tank outlet rough grade pressure valve import that is tightly connected, high-precision pressure valve outlet port.

The measurement mechanism of the axial steady-state permeation rate of said a kind of continuous tow is characterized in that: the fibrous bundle pinch tube adopts resin and glass tube to process, and fibrous bundle pinch tube outer ring is a resin, and inner ring is a glass tube, and glass tube is embedded in the resin.

The measurement mechanism of the axial steady-state permeation rate of said a kind of continuous tow is characterized in that: the fibre density of fibrous bundle is between 40%～70% in the fibrous bundle pinch tube.

The measuring method of the axial steady-state permeation rate of said a kind of continuous tow is characterized in that: may further comprise the steps:

Step 1: open injector valve, the liquid that is stored in the syringe is got in the plastic tubulature by the self gravitation effect; Then close injector valve;

Step 2: open gas tank, regulate pressure valve, make fibrous bundle in the liquid-soaked fibrous bundle pinch tube in the plastic tubulature, when the outlet of fibrous bundle pinch tube has liquid to flow out, think that liquid soaks into fibrous bundle fully;

Step 3: after liquid soaked into fibrous bundle fully, the quality m of the liquid that flows out from the outlet of fibrous bundle pinch tube in the weighing t time was by formula

$k=\frac{\mathrm{M\&eta;\; \&epsiv;}{L}_c}{\mathrm{\&rho;\; TsP}}$ And $k_0=\frac{{{\mathrm{<figure-callout\; id="2"\; label="D\; f"\; filenames="HDA00001637604100011.png"\; state="\{\{state\}\}">D</figure-callout>}}_f}^2}{16k}\frac{{\mathrm{\&epsiv;}}^3}{{(1-\mathrm{\&epsiv;})}^2}$

Simultaneous solution obtains the axial steady-state permeation rate of fibrous bundle k, and s is that fibrous bundle pinch tube inner hole section is long-pending in the formula, L _cBe fibrous bundle pinch tube length, P is the gaseous tension that liquid receives, and ε is a porosity, and η is the viscosity of liquid, and ρ is a density of liquid, D _fBe single fiber beam diameter, k ₀Be the kozeny constant.

Beneficial effect

The present invention is than prior art; Overcome the existing mold measurement because flow section and rising head cross section are inconsistent; Be equivalent to flow of liquid and go out the problem that process is hindered; Fibrous bundle pinch tube outer end does not stop fiber among the present invention, has got rid of because the long-pending influence that changes the fibrous bundle permeability of cross section of fluid channel.The present invention penetrates continuous tow in the cylindrical tube, and liquid through the quality of measuring unit's trickle in the time, calculates the axial steady-state permeation rate of continuous tow from one section outflow of cylindrical tube under the certain pressure gradient.This device is made simple, with low cost, and can reduce edge effect to greatest extent, thereby helps the accurate measurement of the axial steady-state permeation rate of continuous tow.

Description of drawings

Fig. 1: the structural representation of measurement mechanism among the present invention;

Fig. 2: fibrous bundle pinch tube synoptic diagram;

Wherein: 1, gas tank; 2, first class pressure valve; 3, secondary pressure valve threeway; 4, secondary pressure table; 5, second threeway; 6, syringe; 7, to silk; 8, fast inserting; 9, plastic tubulature; 10, fibrous bundle pinch tube; 11, little bowl; 12, brace table.

Embodiment

Below in conjunction with specific embodiment the present invention is described.

With reference to accompanying drawing 1, the measurement mechanism of the axial steady-state permeation rate of the continuous tow in the present embodiment comprises gas tank 1, first class pressure valve 2, secondary pressure valve, syringe 6, plastic tubulature 9 and fibrous bundle pinch tube 10.The measuring accuracy of secondary pressure valve is higher than the first class pressure valve.Secondary pressure valve is made up of secondary pressure valve threeway 3 and secondary pressure table 4.The first class pressure valve is connected with the secondary pressure valve seal.The secondary pressure table adopts pointer pressure, adopts the purpose of two-stage pressure valve to be, realizes injection pressure coarse adjustment and thin tuning.

Gas tank provides injection pressure; The gas tank outlet first class pressure valve import that is tightly connected; The exit seal of secondary pressure valve threeway 3 connects the horizontal port of second threeway 5; The horizontal port of another of second threeway is tightly connected with plastic tubulature one end through fast slotting 8, and the vertical port of second threeway and syringe 6 outlets are through being tightly connected to silk 7.Be inserted with fibrous bundle pinch tube 10 in plastic tubulature 9 other ends, and plastic tubulature and fibrous bundle pinch tube interference fit, its objective is to prevent that liquid from flowing out between pinch tube and plastic tubulature.

Liquid storage is in syringe, and when syringe outlet is opened, liquid can flow into plastic tubulature by the self gravitation effect.Be inserted with fibrous bundle in the fibrous bundle pinch tube, the density of fibrous bundle is generally greater than 40%, and fibre density is between 40%～70% in the practical application.The fibrous bundle pinch tube is the non-osmos tube of rigidity, can directly be processed by metal or plastics, and the fibrous bundle pinch tube adopts resin and glass tube to process in the present embodiment; Fibrous bundle pinch tube outer ring is a resin; Inner ring is a glass tube, and glass tube is embedded in the resin, has avoided the slit between glass tube outer wall and the resin mass; Improved the experiment measuring precision, good reliability.

In the outlet of fibrous bundle pinch tube the little bowl 11 that collects liquid is arranged, after being used to collect liquid, carry out mass measurement.

The measuring process of present embodiment may further comprise the steps:

Step 1: open the syringe outlet valve, the liquid that is stored in the syringe is got in the plastic tubulature by the self gravitation effect; Then close injector valve;

Step 2: open gas tank, regulate pressure valve, make fibrous bundle in the liquid-soaked fibrous bundle pinch tube in the plastic tubulature, when the outlet of fibrous bundle pinch tube has liquid to flow out, think that liquid soaks into fibrous bundle fully;

Step 3: after liquid soaks into fibrous bundle fully, regulate first class pressure valve and secondary pressure valve, reach the demand injection pressure after, the quality m of the liquid that flows out from the outlet of fibrous bundle pinch tube in the time through analytical balance weighing t is by formula

$k=\frac{\mathrm{M\&eta;\; \&epsiv;}{L}_c}{\mathrm{\&rho;\; TsP}}$ And $k_0=\frac{{{\mathrm{<figure-callout\; id="2"\; label="D\; f"\; filenames="HDA00001637604100011.png"\; state="\{\{state\}\}">D</figure-callout>}}_f}^2}{16k}\frac{{\mathrm{\&epsiv;}}^3}{{(1-\mathrm{\&epsiv;})}^2}$

Simultaneous solution obtains the axial steady-state permeation rate of fibrous bundle k, and s is that fibrous bundle pinch tube inner hole section is long-pending in the formula, L _cBe fibrous bundle pinch tube length, P is the gaseous tension that liquid receives, and ε is a porosity, and η is the viscosity of liquid, and ρ is a density of liquid, D _fBe single fiber beam diameter, k ₀Be the kozeny constant.

Claims (5)

1. the measurement mechanism of the axial steady-state permeation rate of continuous tow is characterized in that: comprise gas tank, pressure valve, syringe, plastic tubulature and fibrous bundle pinch tube; The gas tank outlet pressure valve import that is tightly connected; The pressure valve exit seal connects the horizontal port of threeway, and horizontal port of another of threeway and plastic tubulature one end are tightly connected, and the vertical port and the syringe outlet of threeway are tightly connected; Be inserted with the fibrous bundle pinch tube in the plastic tubulature other end, and plastic tubulature and fibrous bundle pinch tube interference fit; Liquid storage is in syringe; Be inserted with fibrous bundle in the fibrous bundle pinch tube; The fibrous bundle pinch tube is the non-osmos tube of rigidity; The outlet of fibrous bundle pinch tube has the container that collects liquid.

2. the measurement mechanism of the axial steady-state permeation rate of a kind of continuous tow according to claim 1 is characterized in that: comprise rough grade pressure valve and high-precision pressure valve; Rough grade pressure valve and the series connection of high-precision pressure valve seal; The be tightly connected horizontal port of threeway of the gas tank outlet rough grade pressure valve import that is tightly connected, high-precision pressure valve outlet port.

3. the measurement mechanism of the axial steady-state permeation rate of a kind of continuous tow according to claim 1 and 2; It is characterized in that: the fibrous bundle pinch tube adopts resin and glass tube to process; Fibrous bundle pinch tube outer ring is a resin, and inner ring is a glass tube, and glass tube is embedded in the resin.

4. the measurement mechanism of the axial steady-state permeation rate of a kind of continuous tow according to claim 3 is characterized in that: the fibre density of fibrous bundle is between 40%～70% in the fibrous bundle pinch tube.

5. the measuring method of the axial steady-state permeation rate of continuous tow is characterized in that: may further comprise the steps:

Step 1: open injector valve, the liquid that is stored in the syringe is got in the plastic tubulature by the self gravitation effect; Then close injector valve;

Step 2: open gas tank, regulate pressure valve, make fibrous bundle in the liquid-soaked fibrous bundle pinch tube in the plastic tubulature, when the outlet of fibrous bundle pinch tube has liquid to flow out, think that liquid soaks into fibrous bundle fully;

Step 3: after liquid soaks into fibrous bundle fully, regulate pressure valve, meet the requirements of injection pressure, the quality m of the liquid that flows out from the outlet of fibrous bundle pinch tube in the weighing t time is by formula

$k=\frac{\mathrm{M\&eta;\; \&epsiv;}{L}_c}{\mathrm{\&rho;\; TsP}}$ And $k_0=\frac{{D_f}^2}{16k}\frac{{\mathrm{\&epsiv;}}^3}{{(1-\mathrm{\&epsiv;})}^2}$

Simultaneous solution obtains the axial steady-state permeation rate of fibrous bundle k, and s is that fibrous bundle pinch tube inner hole section is long-pending in the formula, L _cBe fibrous bundle pinch tube length, P is the gaseous tension that liquid receives, and ε is a porosity, and η is the viscosity of liquid, and ρ is a density of liquid, D _fBe single fiber beam diameter, k ₀Be the kozeny constant.

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