1、Procast充型無法完成的原因及解決方法充型無法完成的原因及解決方法？無法充滿的原因：檢查PREFIXp.ou戊件。1、Solutionisnotconverging（計算程序跳出）原因：邊界條件、材料參數、網格等可能有問題，導致計算不收斂。解決方法：檢查precast中的邊界條件，初始條件等；修改CGSQ參數，采用不用的求解模型；增大收斂公差CONVV（最大0.5）;重新劃網格。2、Acoldshutswitchoffhasbeeninitiatedat（流場計算停止，溫度場計算繼續，但出現異常。ThermalOnlyModel）原因：冷隔算法默認為啟動狀態，如鑄件溫度降低太多，則停止充型

2、計算。如果實際上并無冷隔產生，則需調整參數重新計算。解決方法：調整界面換熱系數，降低冷卻速度。在PREFIXp.dat中添加參數：COLDSHUT0,關閉冷隔算法。裹氣的判斷對于裹氣缺陷的判斷，采用v。1ds選項，觀察充型過程中的氣體分布，同時考慮周圍的排氣情況，及金屬液溫度。主要的參數設置RPProCASTprovidestheaccesstomanyRunparameters,inordertoallowthetreatmentofallkindofsituations.However,foraneverydayuse,onlyafewRunparametershavetobesetorm

3、odified.Thissectionispresentingthemost"popular"RunParametersthatshouldbeset,withproposedvalues,foreachmainfamilyofprocesses.Theseparametersrecommendationsmaybeslightlydifferentfrompreviousversions,asthesolveralgorithmshavebeenmodified.TheserecommendedRunparameterscorrespondtotheone

4、whicharepre-definedinthe"Pre-definedRunParameters"window.Itisthusadvisedtoactivatethe"pre-defined"setcorrespondingtotheprocessandthentosettheappropriatestoppingcriteria.ForallprocessesStoppingcriteria(itisadvisabletosetastoppingcriterioninordertolimittheCPUtimeand

5、avoidunnecessarystorageofresults)TFINALTSTOPPorosityPOROS=1(thismodelisnowrecommendedforallprocesses)MACROFS=0.7FEEDLEN=X(ThevalueFEEDLENdependsuponthesizeofthemushyzoneandthus,thesizeofthecasting.Avaluerangingfromafewmillimeterstoafewcentimetersisrecommended.Thisshouldbecalibratedwithexperiments.Av

6、alueof0isnotadvisedasthiswillproduceauniformmicroporositythroughoutthepart,besidethemacroshrinkage)GravitycastingTimestephandlingDT=1e-3DTMAXFILL=1e-1DTMAX=0.5-5(dependinguponthesizeofthemodelandthusthesolidificationtime)PorosityPIPEFS=0.3GATEFEED=0FillingWSHEAR=2FREESFOPT=1WALLF=0.8LVSURF=0.98Highp

7、ressurediecasting(HPDC)TimestephandlingDT=1e-6to1e-4(itdependsupontheinitialvelocityofthefirststage)DTMAXFILL=1e-2DTMAX=0.2-1(dependinguponthesizeofthemodelandthusthesolidificationtime)PorosityPIPEFS=0.0GATEFEED=1FillingWSHEAR=2FREESFOPT=1WALLF=0.99LVSURF=1.0PINLET=1forapressurefillingorPINLET=0fora

8、velocity/inletfillingLowpressurediecasting(LPDC)TimestephandlingDT=1e-3DTMAXFILL=1e-2(itisimportanttolimitthetimestepduringthefillingofanLPDCpart.Avalueof1e-2isrecommendedforfillingtimeofabout5-20s.).DTMAX=0.2-1(dependinguponthesizeofthemodelandthusthesolidificationtime)PorosityPIPEFS=0.0GATEFEED=1F

9、illingWSHEAR=0(neveruseWSHEAR=2forLPDC)FREESFOPT=1WALLF=0.8LVSURF=1.0PINLET=1forapressurefillingorPINLET=0foravelocity/inletfillingTiltcastingTimestephandlingDT=1e-3DTMAXFILL=1e-1DTMAX=0.5-5(dependinguponthesizeofthemodelandthusthesolidificationtime)PorosityPIPEFS=0.3GATEFEED=0FillingWSHEAR=2FREESFO

10、PT=1WALLF=0.8TILT=1DETACHTOP=1CentrifugalcastingTimestephandlingDT=1e-3DTMAXFILL=1e-1DTMAX=0.5-5(dependinguponthesizeofthemodelandthusthesolidificationtime)PorosityPIPEFS=0.3GATEFEED=0FillingWSHEAR=2FREESFOPT=1WALLF=0.8RELVEL=1由于材料名稱造成的計算出錯在材料數據庫中添加材料時，其名稱中不能包含特殊字符。在運行datacast中，可能會出錯，其出錯信息如下：Anentha

11、lpyfunctionisreferencedin50dataset2whichhasnotbeengiven.分析可能原因：該字符與計算中的某些關鍵字沖突。多次澆注模擬分期澆注，與補澆工藝略有不同，也可以說補澆是一種特殊的分期澆注，完全充滿然后收縮一定量后再次澆注。1、網格不宜太大，澆注系統厚度方向也要保證3層網格以上，（要想得到更好的充型結果，對于其他模擬同樣適用。）2、直澆道和鑄件分開建模，鑄件按正常情況設置熱交換系數，直澆道適當保溫（設置較小的熱交換系數），防止金屬凝固。3、設置正常的邊界條件，定義時間變化曲線。4、運行參數，改LVSURF為一個大于1的值，防止提前終止流場計算。5、在

12、Pdat中手動添加參數：DETACHTOP1（更好的控制金屬液與鑄型頂部的分離）COLDSHUT0（關閉冷隔計算）如何使用niyama準則niyama準則依賴于溫度梯度，網格變化會影響結果，目前看來并不是非常準確當采用默認單位時：cmC色標設置一般為：0-3045使用切面分析內部的危險點（spot）選擇適當的值，設置Cutoff來顯示分布情況一般來說procast自帶的shrinkageporos讓y更準確，但通過niyama準則可以更好的分析早期凝固區域中未形成孤立液相區的缺陷。重力鑄造-參數設置FREESFBAL=2(tobeaddedmanuallyinthep.datfile)This

13、canbeusedinGravitycasting(andonlyinGravitycasting)whenyouhaveanimportanthorizontalfreesurface.Sometimes,thefreesurfaceisgettingquiteagitated.FREESFBAL=2iscalmingdownthisfreesurfacewhichcorrespondsmuchmoretothereality.Inthecode,itcorrespondtoamoreaccuratetreatmentofthemassbalanceatthefreesurface,whic

14、hremovesthekindofinstabilitythatweobservedinlargehorizontalfreesurfaces.重力鑄造-澆注速度設置本帖最后由奔跑于2009-6-120:58編輯實際澆注時，澆包距離澆口一般約1020cm,這時金屬液到達澆口的速度約為1m/s2m/2,所以在設置速度邊界條件時，要注意控制入流面積來保證速度，否則充型結果會產生較大偏差。Inusualcastingconditions,theladle(orcrucible)isveryoftenataminiumof10or20cmabovethetopofthepouringcup.Thus,

15、physically,itisadvisedtosetaninletvelocity(atthelimitofthemodel)between1and2m/sandnotsmaller.Asaconsequence,theinletdiametershouldbesetaccordinglyinordertohavetherightinflowofmetal.Ifatoosmallinletvelocityisdefined(e.g.10cm/s),theinletdiametershouldbetoolargeandduetothestrongaccelerationonthefirstce

16、ntimers,thediameteroftheacceleratingliquidjetwilldecreaseverymuch.Thissituationisquitedifficulttobemodeledandshoulebeavoided.Finally,oneshouldalwaysbecarefulthatthemeshsizebelowafallingliquidstreamshouldbefineenoughinordertohave2-3elementsthroughthethicknessoftheliquidjet.Whenan"inletBC"isdefined,oneshouldalwaysbecarefultosettherightinletsurfacesothatthecorrespondinginletvelocityisnottoosmall(i.e.notsmallerthan1m/s).Tod