CST能否自己設置時間步長
大家好，我想了解一下CST中能否手動設置仿真的時間步長？
我們在仿真的時候，因為不關心一些金屬細節，就把最小網格的絕對值提高了幾倍，這個時候在仿真的時候會出現不穩定，CST會自動調整時間步長，重新計算，然后不穩定，繼續降低時間步長，直到穩定為止，因此我們的問題是能否通過一開始的時候自己設置時間步長？
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.
--------------------------------------------------------------------------------
Units settings:
Dimensions: mm
Frequency:GHz
Time: ns
--------------------------------------------------------------------------------
*** 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...
--------------------------------------------------------------------------------
Number of mesh faces filled with PEC due to fill limit restrictions: 43319
--------------------------------------------------------------------------------
Number of mesh edges filled with PEC due to edge topology restrictions: 866
--------------------------------------------------------------------------------
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，但是之前我看到這句話，我的理解是他說通過降低這個穩定系數來讓求解器計算，而不是直接給我們權限設置步長吧？
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？學習一下嘿嘿
步長是由最小網格尺寸決定的，沒聽說過能單獨設置。
絕大多數情況下仿真不穩定是因為其它的原因：比如波導端口放置在開放邊界以內而且沒有shielding，等等。具體問題具體分析。
最大最小網格比過大會出現這個問題，不是很理解原理
