CST能否自己設(shè)置時間步長
大家好，我想了解一下CST中能否手動設(shè)置仿真的時間步長？
我們在仿真的時候，因為不關(guān)心一些金屬細(xì)節(jié)，就把最小網(wǎng)格的絕對值提高了幾倍，這個時候在仿真的時候會出現(xiàn)不穩(wěn)定，CST會自動調(diào)整時間步長，重新計算，然后不穩(wěn)定，繼續(xù)降低時間步長，直到穩(wěn)定為止，因此我們的問題是能否通過一開始的時候自己設(shè)置時間步長？
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穩(wěn)定系數(shù)來讓求解器計算，而不是直接給我們權(quán)限設(shè)置步長吧？
還有就是不知道你能否舉兩個簡單的例子來說明一下您遇到的情況哇？學(xué)習(xí)一下嘿嘿
步長是由最小網(wǎng)格尺寸決定的，沒聽說過能單獨設(shè)置。
絕大多數(shù)情況下仿真不穩(wěn)定是因為其它的原因：比如波導(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)格比過大會出現(xiàn)這個問題，不是很理解原理
