請(qǐng)教CST MWS中平面波如何設(shè)置TM激勵(lì)
最近在做平面金屬薄膜的THz仿真,需要用平面波進(jìn)行激勵(lì),但里面只有TE模式,不知道如何設(shè)置TM的方式,問(wèn)了別人說(shuō)二者之間有關(guān)系式,但具體也不知道。CST中有一個(gè)金屬球的例子,里面是用平面波激勵(lì)的,但是里面的電極化參數(shù)為數(shù)學(xué)表達(dá)式,看了半天也沒(méi)弄懂。求這方面的高手給指點(diǎn)一下,不甚感激。
CST中的參數(shù)具體是這樣的
電極化方向參數(shù):
X: IIf (phi*zdeg2rad))
Y:IIf(e_vector,cos(phi*zdeg2rad),sin((theta-90)*zdeg2rad)*sin(phi*zdeg2rad))
Z: IIf(e_vector, 0, cos((theta-90)*zdeg2rad))
關(guān)于TM波,我是這樣理解的不知道對(duì)不對(duì),就是說(shuō)把電場(chǎng)的分量只設(shè)置在入射面內(nèi)就行,垂直入射面的方向上不要有電場(chǎng)的分量,你可以試一試這樣行不行,個(gè)人愚見(jiàn)。
但是平面波是TEM波,也就是說(shuō)在波的傳播方向上不可能有電場(chǎng)和磁場(chǎng)的分量了,且垂直于傳播方向的面上電場(chǎng)和磁場(chǎng)矢量是相互垂直的。如果傳播方向是沿Z方向的,那么只能在x、y方向設(shè)置電場(chǎng)分量
如果設(shè)置了Z方向的電場(chǎng)分量,軟件就會(huì)報(bào)錯(cuò)的
木有人嗎?我自己頂一個(gè),免得沉了,我用麥克斯韋方程組計(jì)算了下,設(shè)置X、Y方向的電場(chǎng)計(jì)算后可以得到X、y方向的磁場(chǎng),Z方向?yàn)?,符合平面波的定義,也就是說(shuō)再怎么設(shè)置也是TEM波。在別的帖子上好像看到有人說(shuō)用發(fā)射波和入射波疊加可以得到,但沒(méi)試過(guò)
去問(wèn)問(wèn)CST客戶支持?
平面波有三種模式:TEM、TE、TM;TEM截止頻率是0,其他的都有最小截止頻率,所謂的基模式。想激發(fā)TM模式,可以考慮高次模,然后設(shè)置TEM和TE模式的為0W激勵(lì),試試~
I suppose you can try waveport excitation, it is easy to get cut off frequency with TM mode, the only difference with plane wave is the amplitude variation, it depends on which properties do u look upon, i mean, if you are studying the phase shift or something else not regarding to the amplitude, can have a try.
And if you simulation for the basic characterizations of the material, pls notice the difference between a small scale of box or plate and the really bulk material, the EM performance can be very different, comparing with the theoretical data.(sorry chinese is not available on this PC)
PS, when you setup to increase the scale of the model, then you may have mesh problems; however, a small scale can not present the bulk material properties.