用Fluent验算非定常算例naca0012所遇到的重大问题？？？（重发）

玉米地

迎角按照正弦变化,Am=0.016度，A0=2.51度，Ma=0.755  Re=550000时
迎角变化通过udf函数引入：
1.剪切频率k=0.0060961(对应角频率为10)升力环为：
其图像与x轴（代表迎角）成45度；
2.剪切频率k=0.0214(对应角频率为35.1)升力环为：
其图像与x轴（代表迎角）基本成45度；
3.剪切频率k=0.0814(对应角频率为135.528)升力环为：
其图像与x轴（代表迎角）成135度；这个计算状态有实验数据可以对比的，
可是很显然计算出来的升力环应该与迎角度轴成45度，且基本比得上，
可是我计算出来的却是成135度，明显不对！
问题：为什么随着剪切频率的增加，所计算出来的升力环出现倒象，从45度夹角
变成135度？请问还是还有哪里需要具体设置的地方我没设置好？请各位大侠
帮助小弟解决一下！
急用急用！！！！！
3个所计算的升力环可参见附件：

玉米地

急死我啦！
看来还没遇到同行哇？
还是我没表述清楚，其实只需下载附件就一幕了然了（有这一操作估计没人愿意折腾了）！
还是要麻烦在座的各位同行大侠了！
帮忙分析分析，要不然这个十一假就费啦！肯定会很惨啦！

玉米地

我再具体表述一下：
naca0012实验数据（k=0.0814）表明:
最大升力基本上都发生在最大迎角处。而我的计算结果表明小剪切频率(k=0.0060961)时基本满足上述规律，可是随着剪切频率k的增加，最大升力出现了严重的滞后，即最大升力不是随着正弦变化的迎角增加而相应地都达到或接近最大值，最后导致升力环倒置现象(与迎角轴呈现大于90度的夹角)。
可以确定的是上述计算结果的升力、阻力、力矩都出现了周期性变化的，表明计算结果已收敛，但是显然与实验数据(k=0.0814)对比收敛到了一个错误的结果。
我现在真不知道问题出在哪块儿？

玉米地

十一日，大家节日快乐！
我依然还处于郁闷中...
问题已经困扰我半个月了！
谢谢过往的访客们！

玉米地

2007年10.2日：
通过udf引入迎角变化：Define/Boundary Conditions/pressure-far-field...
在x方向引入cos，在y方向引入sin。网格仅生成一次初始的，即通过改变迎角实现
非定常计算！
（针对k=0.0814，此剪切频率有实验数据可对比）
方法一：
real alpha=(0.016+2.51*sin(133.528*t))/180*pi;
此时升力曲线呈周期性，但是相位有严重滞后.计算2个周期，每周期100个时间步。
具体数据如下()：
time                       cl
0.00047055  0.0012348817
0.000941100010.0012027664
0.00141165           0.0012593764
0.0018822           0.0013464591
0.00235274990.0014364101
0.0028233           0.0015202348
0.00329385           0.001598361
0.0037644           0.001685658
0.00423495010.0018161021
0.00470549990.0020414787
0.00517605010.0024328278
0.00564659990.0030685347
0.00611715020.0040442532
0.0065877           0.0054525148
0.00705825030.0073426572
0.00752880010.0097974145
0.00799935030.01280788
0.00846990010.016461629
0.00894044990.020689404
0.00941099970.025465657
0.00988155040.030802806
0.0103521   0.036668779
0.01082265           0.043062956
0.0112932           0.049918621
0.01176375           0.057227478
0.0122343           0.064962141
0.01270485           0.07312676
0.0131754           0.081703657
0.01364595           0.090653354
0.0141165010.09994024
0.014587050.10956962
0.01505760.11954201
0.015528150.12982839
0.0159987010.14037495
0.016469250.151105
0.01693980.16194615
0.0174103510.17290219
0.01788090.1839048
0.0183514510.19492862
0.0188219990.20581331
0.019292550.21663894
0.0197631010.2272069
0.020233650.23754051
0.02070420.24761743
0.0211747490.25724732
0.02164530.26646038
0.0221158510.27499348
0.02258640.28298237
0.023056950.29043089
0.0235274990.29725057
0.023998050.30325616
0.0244686010.30823037
0.024939150.31224699
0.02540970.31525356
0.0258802510.31722643
0.02635080.31829823
0.0268213510.31836057
0.02729190.31827979
0.027762450.31827625
0.0282330010.31621066
0.028703550.31611771
0.0291741010.31175534
0.0296446490.30694295
0.03011520.3009777
0.0305857510.29382341
0.03105630.28552203
0.0315268490.2761447
0.0319974010.2655696
0.032467950.25376827
0.0329384990.2408972
0.0334090520.22715062
0.03387960.21275308
0.0343501490.1978592
0.0348207020.18217384
0.0352912510.16556082
0.03576180.14841179
0.0362323490.13077552
0.0367029010.11255955
0.037173450.093967152
0.0376439990.075025673
0.0381145510.055758055
0.03858510.036387692
0.0390556490.016833068
0.039526202-0.0027239928
0.039996751-0.022233873
0.0404673-0.041599491
0.040937852-0.060740419
0.041408401-0.079590276
0.04187895-0.098077852
0.042349499-0.11615212
0.042820051-0.13377105
0.0432906-0.1509596
0.043761149-0.16774121
0.044231702-0.18401031
0.044702251-0.19970663
0.045172799-0.21470941
0.045643352-0.22879579
0.046113901-0.24192814
0.04658445-0.25410263
0.047054999-0.26524218
0.047525551-0.2753116
0.0479961-0.2840855
0.048466649-0.2916428
0.048937201-0.29799739
0.04940775-0.30310271
0.049878299-0.3067677
0.050348852-0.3091089
0.050819401-0.31023642
0.05128995-0.31011724
0.051760502-0.30889469
0.052231051-0.30665806
0.0527016-0.30344899
0.053172149-0.29922824
0.053642701-0.29395793
0.05411325-0.28760357
0.054583799-0.28008422
0.055054352-0.27132215
0.055524901-0.26136389
0.055995449-0.25025304
0.056466002-0.23810561
0.056936551-0.2251445
0.0574071-0.21152412
0.057877649-0.19716633
0.058348201-0.18185463
0.05881875-0.16560692
0.059289299-0.14872696
0.059759852-0.13131018
0.0602304-0.1132681
0.060700949-0.094830689
0.061171502-0.075933601
0.061642051-0.056735154
0.0621126-0.03737635
0.062583148-0.017807923
0.0630536970.0017824446
0.0635242540.021323008
0.0639948030.040722423
0.0644653510.059886555
0.06493590.078747928
0.0654064490.097237885
0.0658769980.11530378
0.0663475470.13290507
0.0668181030.15005023
0.0672886520.16677119
0.0677592010.18296776
0.068229750.19856062
0.0687002990.21343453
0.0691708480.22745069
0.0696414040.24052682
0.0701119530.25259992
0.0705825020.26371197
0.071053050.27365558
0.0715235990.28242223
0.0719941480.28998846
0.0724646970.29634567
0.0729352530.3014646
0.0734058020.30522624
0.0738763510.30757662
0.07434690.30868202
0.0748174490.30863767
0.0752879980.30743397
0.0757585540.30519862
0.0762291030.30197074
0.0766996520.2977838
0.0771702010.29257187
0.077640750.28631439
0.0781112980.2788636
0.0785818470.27012106
0.0790524040.26032175
0.0795229520.24939023
0.0799935010.23746005
0.080464050.22473894
0.0809345990.2113606
0.0814051480.19718886
0.0818757040.18206805
0.0823462530.16599676
0.0828168020.14928298
0.0832873510.13203425
0.08375790.1141532
0.0842284490.095865719
0.0846989970.077141621
0.0851695540.058085941
0.0856401030.038880758
0.0861106510.0194576
0.08658121.9280917e-05
0.087051749-0.01939362
0.087522298-0.038656762
0.087992847-0.057693653
0.088463403-0.076432837
0.088933952-0.094803718
0.089404501-0.11275501
0.08987505-0.13024187
0.090345599-0.14726194
0.090816148-0.16385635
0.091286704-0.17993862
0.091757253-0.19540283
0.092227802-0.21018799
0.092698351-0.22411355
0.093168899-0.23708616
0.093639448-0.24906084
0.094109997-0.26005891
方法二：
real alpha=(0.016+2.51*sin(133.528*t/180*pi))/180*pi;
此时升力曲线呈周期性，但是相位没有滞后.但是与实验数据相比明显不对，升力环扁得厉害！
计算2个周期，每周期100个时间步。
具体数据如下()：
time                       cl
0.0269606750.013923446
0.0539213490.042200773
0.0808820280.056067875
0.1078427           0.059211667
0.13480337           0.098491316
0.161764060.12357125
0.188724730.13798958
0.21568540.17764829
0.242646070.1964619
0.269606740.2223092
0.296567410.24644262
0.323528110.26939077
0.350488780.29524933
0.377449450.31297883
0.404410120.33424701
0.431370790.34702333
0.458331470.36166659
0.485292140.37072964
0.512252810.37975898
0.539213480.3853789
0.566174150.39088129
0.593134820.39434277
0.620095490.39738895
0.647056220.39935149
0.674016890.40008258
0.700977560.3992451
0.727938230.39728931
0.754898910.3940426
0.781859580.38948332
0.808820250.38398941
0.835780920.3772531
0.862741590.36941505
0.889702260.35925799
0.916662930.34736343
0.94362360.33454985
0.970584270.32198677
0.997544940.30993171
1.02450560.29724579
1.05146630.28156104
1.0784270.26299428
1.10538770.24049983
1.13234830.21887187
1.1593090.19830448
1.18626960.17548227
1.21323040.15197556
1.2401910.12842895
1.26715170.1038938
1.29411240.078427032
1.32107310.053223087
1.34803380.027235442
1.37499440.0010805753
1.4019551-0.025222454
1.4289157-0.051754202
1.4558765-0.078378325
1.4828371-0.1050488
1.5097978-0.13141185
1.5367584-0.15757801
1.5637192-0.18300689
1.5906798-0.20785932
1.6176405-0.23156496
1.6446011-0.25423997
1.6715618-0.2748569
1.6985224-0.29394063
1.7254832-0.31171223
1.7524439-0.32640924
1.7794045-0.33925484
1.8063653-0.35146302
1.8333259-0.3620667
1.8602866-0.37097865
1.8872472-0.37834689
1.9142079-0.38422178
1.9411685-0.38824243
1.9681293-0.3909927
1.9950899-0.39239735
2.0220506-0.39285112
2.0490112-0.39256067
2.0759718-0.39122519
2.1029327-0.38846689
2.1298933-0.38438925
2.1568539-0.37862455
2.1838148-0.37150516
2.2107754-0.36257679
2.237736-0.35225642
2.2646966-0.34145326
2.2916574-0.33048883
2.3186181-0.31930966
2.3455787-0.30730702
2.3725393-0.29339763
2.3995001-0.27685804
2.4264607-0.2568244
2.4534214-0.23437151
2.480382-0.21371552
2.5073428-0.19295385
2.5343034-0.16986501
2.561264-0.14670923
2.5882249-0.12322339
2.6151855-0.098247493
2.6421461-0.073074252
2.6691067-0.047625354
2.6960676-0.021692173
2.72302820.0044948735
2.74998880.030923988
2.77694940.057518544
2.80391030.08417477
2.83087090.11086652
2.85783150.13728695
2.88479210.16340091
2.91175290.18887589
2.93871360.21370367
2.96567420.23733737
2.99263480.25974346
3.01959560.28016169
3.04655620.29913655
3.07351680.31677721
3.10047770.33094898
3.12743830.34394227
3.15439890.3560438
3.18135950.36641684
3.20832040.37533544
3.2352810.38239602
3.26224160.38796537
3.28920220.39205257
3.31616310.39468697
3.34312370.39613355
3.37008430.39700664
3.39704490.39681244
3.42400570.39531517
3.45096640.39253016
3.4779270.38836735
3.50488780.38275609
3.53184840.37580809
3.5588090.36722155
3.58576970.35683921
3.61273050.34553749
3.63969110.33405376
3.66665170.32251088
3.69361230.310682
3.72057320.29747084
3.74753380.28132552
3.77449440.26228918
3.8014550.23966863
3.82841590.21835373
3.85537650.1978042
3.88233710.17498941
3.90929790.15158234
3.93625860.12805612
3.96321920.10349089
3.99017980.078112461
4.01714040.052862992
4.04410120.026941829
4.07106210.00077057947
4.0980225-0.025501281
4.1249833-0.052025987
4.1519437-0.078627245
4.1789045-0.10527501
4.2058654-0.13162228
4.2328258-0.15775889
4.2597866-0.18317215
4.2867475-0.20800859
4.3137078-0.23168277
4.3406687-0.25433578
4.3676295-0.27494978
4.3945899-0.29402606
4.4215508-0.3117358
4.4485111-0.32649167
4.475472-0.33928982
4.5024328-0.35144157
4.5293932-0.3620639
4.556354-0.37097989
4.5833149-0.37836886
4.6102753-0.38416639
4.6372361-0.3882948
4.6641965-0.39103666
4.6911573-0.39242507
4.7181182-0.39280459
4.7450786-0.39230831
4.7720394-0.39100515
4.7990003-0.3882596
4.8259606-0.38400361
4.8529215-0.37843606
4.8798823-0.37132903
4.9068427-0.36236486
4.9338036-0.35216042
4.9607639-0.34143824
4.9877248-0.33050506
5.0146856-0.31934524
5.041646-0.30729575
5.0686069-0.2933177
5.0955677-0.27674553
5.1225281-0.25664112
5.1494889-0.23421859
5.1764498-0.21359673
5.2034101-0.19282049
5.230371-0.16973759
5.2573314-0.14659929
5.2842922-0.12311693
5.3112531-0.098137349
5.3382134-0.072968108
5.3651743-0.047519038
5.3921351-0.021596646
再次请教各位路过得大侠：
针对这个问题，不知这样计算对不对，是否需要采用动网格技术来实现翼型振荡的数值模拟呢？
如果是那么具体得步骤或参考资料又将如何呢？
谢谢！

玉米地

    从10.3日开始我的网变得不好使，总是上不去。到现在啦终于能上去了，怀着激动得心情看看有没有回帖建议，又是一片失望。或许我本来就不应该把希望寄托在论坛上，哪怕是那么一点点希望都不应该寄托的。很多事只能靠自己和认识我自己的人，茫茫网络，茫茫人海，能给予相互帮助的其实是少得可怜得，其实这也是非常正常不过得，哪有恰巧得事呢（你的问题在短时间内能刚好遇到同行）！
    革命未成功，同志还需努力！
论坛还是个交流得地方，但不是每个人都能交流得到的地方。专业性强些的问题就更别指望了！
    有点牢骚满腹了，不好意思！
    还是希望大家继续支持这个论坛的，毕竟对于新手而言还是挺不错的！

慎僧

alpha=(0.016+2.51*sin(133.528*t))/180*pi;
估计是你的攻角正负问题吧，一般我们认为抬头为正，而软件一般遵循右手定则，即拇指指向的为正，刚好与抬头为正相反。