CST能否自己設(shè)置時(shí)間步長(zhǎng)
大家好，我想了解一下CST中能否手動(dòng)設(shè)置仿真的時(shí)間步長(zhǎng)？
我們?cè)诜抡娴臅r(shí)候，因?yàn)椴魂P(guān)心一些金屬細(xì)節(jié)，就把最小網(wǎng)格的絕對(duì)值提高了幾倍，這個(gè)時(shí)候在仿真的時(shí)候會(huì)出現(xiàn)不穩(wěn)定，CST會(huì)自動(dòng)調(diào)整時(shí)間步長(zhǎng)，重新計(jì)算，然后不穩(wěn)定，繼續(xù)降低時(shí)間步長(zhǎng)，直到穩(wěn)定為止，因此我們的問題是能否通過一開始的時(shí)候自己設(shè)置時(shí)間步長(zhǎng)？
logfile在二樓粘貼一下
*** Warning ***
The calculation seems to be unstable! Transient solver is restarted with a
scaled timestep by 0.85.
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Units settings:
Dimensions: mm
Frequency:GHz
Time: ns
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*** Warning ***
34 mesh cells are represented in staircase mode and have been filled with PEC.
8 mesh faces are represented in staircase mode and have been filled with PEC.
More...
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Number of mesh faces filled with PEC due to fill limit restrictions: 43319
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Number of mesh edges filled with PEC due to edge topology restrictions: 866
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Boundary conditions:
可以，回答完畢。CST MWS幫助文件《Special Solver Parameters - General》：
Stability factor for timestep: Enter here a stability factor that will be multiplied to the current valid stability limit for the numerical timestep. In case that a time domain calculation shows some slight effects of instability, a small reduction of the stability factor might recover a stable state. Note: Choosing a factor greater than one is not advisable and will likely produce instability.
不過我所見過的所有instability的情況都是其它的原因。
謝謝何大哥的回復(fù)，但是之前我看到這句話，我的理解是他說通過降低這個(gè)穩(wěn)定系數(shù)來讓求解器計(jì)算，而不是直接給我們權(quán)限設(shè)置步長(zhǎng)吧？
還有就是不知道你能否舉兩個(gè)簡(jiǎn)單的例子來說明一下您遇到的情況哇？學(xué)習(xí)一下嘿嘿
步長(zhǎng)是由最小網(wǎng)格尺寸決定的，沒聽說過能單獨(dú)設(shè)置。
絕大多數(shù)情況下仿真不穩(wěn)定是因?yàn)槠渌脑颍罕热绮▽?dǎo)端口放置在開放邊界以內(nèi)而且沒有shielding，等等。具體問題具體分析。
最大最小網(wǎng)格比過大會(huì)出現(xiàn)這個(gè)問題，不是很理解原理
