压力容器
壓力容器
압력용기
2015年
3期
20-28
,共9页
魏协宇%陈冰冰%郑浣琪%邓志军%高增梁
魏協宇%陳冰冰%鄭浣琪%鄧誌軍%高增樑
위협우%진빙빙%정완기%산지군%고증량
外压圆筒%初始缺陷%傅里叶级数%一致缺陷模态法
外壓圓筒%初始缺陷%傅裏葉級數%一緻缺陷模態法
외압원통%초시결함%부리협급수%일치결함모태법
cylinders under external pressure%initial imperfections%Fourier series%eigenmode method
分别由简化傅里叶级数模型与一致缺陷模态模型构造带初始几何偏差的外压圆筒,采用ANSYS有限元进行非线性模拟,当模拟得到的临界压力为理想圆筒临界压力的80%时,得到这两种模型对应的几何偏差e值曲线。将上述曲线以及ASME Ⅷ-1(或GB 150)、ASME Ⅷ-2所规定的e值、Annaratone所著一书中理论公式求得的e值进行比较分析,结果表明:一致缺陷模态法所得结果偏保守;在L/Do较小时,采用ASME Ⅷ-1中规定的e值,其结果可能是冒进的;在Do/t 与L/Do相同时,由简化傅里叶级数模型得到的e值,明显高于一致缺陷模态模型得到的e值。WRC公报(443号)提到了试验值(p-Test)大于理论值(p-Theory)的现象,这与初始几何偏差在实际情况下和理论模型所假设的初始几何偏差不同有关;由ASME Ⅷ-2规定得出的e值均大于简化傅里叶级数模型得到的e值,说明ASME Ⅷ-2对于e值的规定是可行的。
分彆由簡化傅裏葉級數模型與一緻缺陷模態模型構造帶初始幾何偏差的外壓圓筒,採用ANSYS有限元進行非線性模擬,噹模擬得到的臨界壓力為理想圓筒臨界壓力的80%時,得到這兩種模型對應的幾何偏差e值麯線。將上述麯線以及ASME Ⅷ-1(或GB 150)、ASME Ⅷ-2所規定的e值、Annaratone所著一書中理論公式求得的e值進行比較分析,結果錶明:一緻缺陷模態法所得結果偏保守;在L/Do較小時,採用ASME Ⅷ-1中規定的e值,其結果可能是冒進的;在Do/t 與L/Do相同時,由簡化傅裏葉級數模型得到的e值,明顯高于一緻缺陷模態模型得到的e值。WRC公報(443號)提到瞭試驗值(p-Test)大于理論值(p-Theory)的現象,這與初始幾何偏差在實際情況下和理論模型所假設的初始幾何偏差不同有關;由ASME Ⅷ-2規定得齣的e值均大于簡化傅裏葉級數模型得到的e值,說明ASME Ⅷ-2對于e值的規定是可行的。
분별유간화부리협급수모형여일치결함모태모형구조대초시궤하편차적외압원통,채용ANSYS유한원진행비선성모의,당모의득도적림계압력위이상원통림계압력적80%시,득도저량충모형대응적궤하편차e치곡선。장상술곡선이급ASME Ⅷ-1(혹GB 150)、ASME Ⅷ-2소규정적e치、Annaratone소저일서중이론공식구득적e치진행비교분석,결과표명:일치결함모태법소득결과편보수;재L/Do교소시,채용ASME Ⅷ-1중규정적e치,기결과가능시모진적;재Do/t 여L/Do상동시,유간화부리협급수모형득도적e치,명현고우일치결함모태모형득도적e치。WRC공보(443호)제도료시험치(p-Test)대우이론치(p-Theory)적현상,저여초시궤하편차재실제정황하화이론모형소가설적초시궤하편차불동유관;유ASME Ⅷ-2규정득출적e치균대우간화부리협급수모형득도적e치,설명ASME Ⅷ-2대우e치적규정시가행적。
Simplified Fourier series and eigenmode-affine geometric imperfections are employed to build cylindrical shells with initial geometric deviations under external pressure in nonlinear ANSYS finite ele-ment analysis.The curves of e (the deviation value)are obtained when simulation pressure is 80%of the critical pressure of prefect cylinders.Compare the simulation result with the e curves obtained by using the theoretical formulas of a book written by Annaratone and the regulations of ASME Ⅷ-1 ,ASME Ⅷ-2.It shows that:the simulation critical pressure is conservative when eigenmode-affine is employed to build the geometric imperfections;When the value of L/Do is small,the value of e from ASME Ⅷ-1 maybe aggres-sive;The value of e obtained by simplified Fourier series is bigger than the one obtained by eigenmode-affine geometric imperfections at the same value of Do/t and L/Do .The real reason why the value of p-Test is bigger than the value of p-Theory which is mentioned in WRC bulletin (No.443)is that the re-alistic initial geometric deviations are irregular but the initial geometric deviations introduced in theoreti-cal formulas are regular which are similar to eigenmode-affine geometric imperfections;The value of e from ASME Ⅷ-2 is smaller than the value of e obtained by simplified Fourier series,so the regulations of value e is feasible.