A general second-order system is used here, for simplicity, to represent the mill stand dynamics to study third-octave-mode chatter.
- DaSaGwaLv 78 years agoFavorite Answer
I cannot type Chinese, so I have found a close explanation for "octave" (倍频程).
倍頻程是指兩個頻率之比為2:1的頻程。人耳可聞的聲音、頻率在20~20000HZ之間，而其中心頻率為31.5、 63、 125、 250、 500、 1000、 2000、 4000, 8000、16000HZ。在嗓聲控制的現場測試中，通常它只用63~8000HZ分為8個倍頻程。用它來表示某個寬廣的聲頻範圍。
The above explanation is for human ears. The question you have is for a rolling machine. This kind of machine, when in operation, can also produce "octave". (due to vibration, or oscillation). It will also have similar "central frequency" for octave. Hence,
"third-octave-mode" means the third central frequency (第三倍频程模式), take above octave frequency for human ears as an example, it will be "250Hz". For a rolling machine, it is between 125Hz and 240Hz.
This problem is from a rolling machine. The reason people want to study "third-octave-mode" is because it causes the most damage to the machine itself and produces an uneven surface of the rolled steel. The next octave to study is "fifth-octave-mode". However, "fifth-octave-mode" can be suppressed much earlier than "third-octave-mode".
If you want to know more about octave (倍頻程), you can refer to
- 8 years ago
A general second-order system is used here, for simplicity, to represent the mill stand dynamics to study third-octave-mode chatter.的意思是(一般的二階系統，為簡單起見，這裡使用的是，代表軋機機架的動力學研究3倍頻程模式的喋喋不休。)