Compound the key that pushs a technology in all is in all the design of extruder head. Belt feed makings piece in all extruder head because its are cabinet, accurate and times accept favour. Dog the develop and determines final interface shape of interfacial position is compound the key that presses a technology to apply successfully in all. The article uses numerical value to analyse technical imitate to feed position of interface of the polymer in makings piece to distributing, undertook experiment test and verify. Single data products often has limitation, cannot the product performance characteristics that economic ground satisfies an expectation, cannot satisfy people to go up to the certain character of goods, apparent is special requirement. Below this kind of circumstance, emerge as the times require of composite material goods. Squeeze a technical brief introduction to be used at making in all multilayer the method of composite material is Baconian rise to basically have Tu Bu law, lamination law and push a way in all 3 kinds. The compound technology of besmear cloth law and lamination law is similar, be told simply even if make with binder a film and another base material (namely filmy, paper or tinsel) union, or multilayer film and base material union rise. And squeezing law in all is a kind when develop quickly in recent years newer multilayer composite material machines a method. It is a variety of polymer fuse-element by head of a special model the assemble is together, finalize the design via refrigeration and get multilayer a shape or filmy shape push compound product in all. Current, the production that China pushs a compound product in all already gradually hasten is mature, use what this craft produces to pack compound film to have cut off quality tall, intensity tall, hear resistance is good, without rudimental dissolvent pollution, quality wall of light, film is thin wait for a characteristic. Accordingly, it is being used widely with its distinct advantage. Additional, this craft simplified to produce working procedure greatly not only, and the dosage that also reduced expensive stock, monolayer film is the thinnest can amount to 2 μ M, it is more compound than using besmear cloth law or lamination method craft can save the manufacturing cost of 30% . The key that pushs compound technology in all is in all the design of extruder head, use at present more in all extruder head has 3 sort model: Much flow path in all extruder head, belt feeds makings piece in all extruder head and much flow path and feed makings piece combination in all extruder head. Among them, belt feed makings piece in all extruder head because its are cabinet, accurate and times accept favour. Compound the core that squeezes an academic research in all is how to dog the development of interfacial position and the shape that determine final interface. The domestic research in this respect is very few, abroad has had many researcher to pursueing the job of this respect, but the content of research mostly confine Yu Yiwei or planar are compound squeeze in all piece. The article will introduce model of non Newton fluid, imitate rectangle is sectional in feeding makings piece three-dimensional squeeze a polymer interface position to distributing in all. The model builds what geometrical model considers here is A/B/A three-layer polymer squeezes those who give interfacial seat to distributing in all, the sectional appearance that feeds makings piece is rectangle. According to symmetry, we need computational 1/4 only feed makings piece can. Its corresponding dimensional geometry figure is shown 1 times like the graph. Feeding part of C of makings piece entrance, flow path is divided into two independent parts by fender F, polymer A and polymer B hold these two independent flow path to be in at D respectively confluent. E place is the exit that feeds makings piece. What simulative wanting here is choose the polymer interface place that feeds E of makings piece exit from the confluent place D of makings shedding distributing reach figure. The 1/4 that the graph shows 1 times feeds the geometrical parameter of makings piece to be: Sectional tall H (Z to) for 4mm, wide W (Y to) for 12mm, CD end length is 20mm, DE end length is 15mm. The control equation that the three-dimensional isotherm of compound flow often flows surely is fuse-element of polymer of mathematical model description: (1) (2) among them: (3) in type, ρ I is the density of body of I laminar flow, p is pressure, for unit tensor, for the viscosity of body of I laminar flow, it is the function that cuts rate, speed vector is: (4) Nextpage among them, u, V, W is speed in coordinate X, Y, Z3 the heft on direction, , , it is the unit vector on direction of X, Y, Z respectively. Need of completely three-dimensional analysis can mirror polymer to shed those who become characteristic in the round this compose equation, apparent, the power that is used extensively leads a model to satisfy this requirement very hard, be in because of what what it offers low cut area and tall the viscosity cost that cuts speed extent determines with the experiment the value differs very far. And Carreau model is applied to from low to tall whole cut area, so here chooses Carreau model to regard our calculative as this compose equation. (5) cuts rate γ by type ( of 6) computation (6) cuts rate tensor to define the that it is among them (the η in 7) type 0 to rate γ is cut to tend below referenced temperature the 0 viscosity when are worth; L is flabby time. Interfacial position decides us to assume really a particle moves to export along the interface that squeezes a polymer in all all the time from the entrance that feeds makings piece, so the athletic contrail of this particle is a line on this interface, if enough such much line join rises, formed the whole interface between polymer. So, search the athletic contrail that gives such particle, also can decide to push an interfacial position between polymer in all. The particle that satisfies this kind of requirement is in the direction of going from place to place of position of polymer interface either inevitable as tangent as the interface, its corresponding description equation is: (8) equation (8) it is stringent condition of place of motion of particle edge interface, its motion contrail can decide by next type: (9) (10) in type, t is time. Have: (11) by equation (11) can get: (12) with (13) attrib border condition by equation (1) , (2) seek solution whole the 3 speed heft in feeding makings piece and pressure, still need to give attrib border condition. Assume feeding makings piece entrance and exit, flow is sufficient progress, have: With ＝ of U ＝ V of 0 (14) among them, coordinate X is to push a way. Get without slippage by mural face: (15) be in in the interface of fuse-element A and B, speed is successive, namely: (16) Nextpage is same, be in in the interface tangential stress also should be balanced, namely: (17) among them, cut vector with vector of the law outside the unit that is interfacial S place respectively and unit. Oversight interface is in the influence of exterior tension, the law of the fuse-element A that the interface is in and B balances type to be to stress: (18) considering the symmetry that feeds structure of makings piece geometry, in Y ＝ 0 with Z ＝ 0 punish are not existing symmetrical plane. The symmetrical and attrib border condition that is in in symmetrical face is respectively: (19) (20) computational measure is begun by assumed interfacial position, use area of computation of disperse of limited volume law, use program of computation of FORTRAN language work out, if the graph is shown 2 times,its corresponding reseau is decorated. Computational measure is: 1 by equation (1) with equation (2) seek the rate value that sees each node point and pressure cost. 2 apply equation by gotten speed field (5) computational viscosity field. 3 repeat measure 1 with 2, till speed field and pressure field are convergent. The speed field with 4 convergent basises, by equation (12) and (13) computational interface position. 5 differentiate afresh by updated interfacial position computational region, repeat measure 1, 4, till interfacial position is convergent. Place of Gifford of no less than points out in that way, when computational interface position, need chooses likely low flabby factor, exorbitant flabby factor can bring about interfacial position to appear in convergent process bigger oscillation. The low flabby gene that we introduce is 0. 2. We choose imitate result ethylene, polyvinyl alcohol copolymer (EVOH) as lining material, and outer have low density polyethylene respectively (LDPE) spend polyethylene with high density (HDPE) can offer an alternative. Adopt a change outer material, can combine those who differ to push a system in all. Relevant material attribute parameter already at the watch 1 in give out. Graph 3 gave out to feed position of interface of polymer of makings piece exit distributing. In avery kind of viscosity comparing falls, enter the mouth bulk shedding rate is maintained the value is secured in, namely: Qb/ Qa ﹦ 6.
03. Nextpage from the graph 3 can see: Reduce as what viscosity compares, interfacial position is elevatory; Plant in either below viscosity comparing, interfacial appearance is bending, be in mural face place especially, interfacial bending is out of shape degree bigger. Notice, below two kinds of cases that show in the graph, polymer A has the tendency of B of wrap up polymer from beginning to end. This and " the tendency that low viscosity fuse-element has fuse-element of wrap up tall viscosity " this one rule is conform to. Experiment we undertook experimenting study to afore-mentioned imitate on lab nose. Place is two Φ with equipment the odd screw extruder of 45, a rectangular and sectional compound nose; To assure the constant temperature condition of nose cliff face, we use chuck type structure to nose, constant temperature conduction oil is connected inside nose chuck; Nose entry point expects system of feedback of a thermocouple controls Wen You; Place sees a table with stock and attribute 1. Graph 4 it is figure of contrast of test result and imitate result. From the graph 4 we can see, differ in two kinds 0 cut viscosity to compare, the interfacial position of the experiment compares computational position on the high side, experiment namely interfacial position compares computational position more stand by nose on mural face. The cause that creates this kind of appearance is: Computational cost is made below isothermal hypothesis condition, although place of nose cliff face connects constant temperature oil, but the heat conduction performance of plastic fuse-element is poor, because cut action,be in in effective treatment, the temperature of the fuse-element inside nose is not constant temperature actually, caused computational value and the error that imitate is worth so. Near the width wall surface that nearing nose (namely 12mm cliff face) , test value and imitate value consistency are better, the conduction oil that this shows to mural face is in constant temperature is very good to arriving since nose lukewarm control function. In the graph 4 in about place of nose width 8mm, the interfacial computation value below rate of two kinds of viscosity and imitate worth difference are bigger, because be in those who stand by mural face to be in fuse-element to cut rate on one hand,this basically is bigger, corresponding temperature rise is faster; On the other hand, the constant temperature conduction oil of nose undertakes enforcing cooling to fuse-element again, below this both combined action, at nose width about 8mm place produced the biggest temperature rise, caused computational value and the difference that imitate is worth to want big appearance at other place relatively consequently. Conclusion we squeeze position of side of out of bounds to distributing in all through the analysis characteristic, gave out to dog the analytic expression that polymer pushs position of side of out of bounds in all; Use Carreau to flow change model, program of computation of proper motion work out seeks solution the polymer in feeding makings piece is three-dimensional stream, then imitate the polymer in feeding makings piece squeezes position of side of out of bounds to distributing in all reach its figure. Imitate result makes clear: Push position of side of out of bounds and appearance and stock in all 0 cut viscosity comparing to concern; In entry point the complex material with each even ply flows after the course feeds makings piece, in its exit, interfacial appearance already by twist. Here what we gave out to beg solution non Newton fluid first is multilayer the imitate method that pushs interfacial position in all, gave out rectangular and sectional the imitate result that feeds the polymer in makings piece to squeeze an interface in all. In the meantime, pass experiment test and verify the feasibility of the method that the computational polymer that article place offers squeezes position of side of out of bounds to distributing in all. CNC Milling
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