解放军理工大学学报(自然科学版)
解放軍理工大學學報(自然科學版)
해방군리공대학학보(자연과학판)
JOURNAL OF PLA UNIVERSITY OF SCIENCE AND TECHNOLOGY(NATURAL SCIENCE EDITION)
2014年
1期
81-88
,共8页
张文静%朱首贤%阮鲲%彭剑
張文靜%硃首賢%阮鯤%彭劍
장문정%주수현%원곤%팽검
长江冲淡水%低盐水团%正压不稳定%动力机制
長江遲淡水%低鹽水糰%正壓不穩定%動力機製
장강충담수%저염수단%정압불은정%동력궤제
the Changjiang diluted water%low-salinity water lens%barotropic instability%dynamic mechanism
针对长江冲淡水扩展区域低盐水团现象,开展正压不稳定机制研究。基于1977年夏季低盐水团的演变特征分析,将初始形成的低盐水团看成小扰动,建立小扰动方程描述低盐水团运动,采用WKBJ方法求解小扰动方程,讨论了快波过程(重力惯性波)和慢波过程(余流作用)对低盐水团的影响,并给出了受慢变波包影响的能量演变方程。研究表明,快波过程对低盐水团基本没影响,低盐水团从口门向口外东北海域运动过程中,由于水深加大,慢波过程有利于低盐水团发展。
針對長江遲淡水擴展區域低鹽水糰現象,開展正壓不穩定機製研究。基于1977年夏季低鹽水糰的縯變特徵分析,將初始形成的低鹽水糰看成小擾動,建立小擾動方程描述低鹽水糰運動,採用WKBJ方法求解小擾動方程,討論瞭快波過程(重力慣性波)和慢波過程(餘流作用)對低鹽水糰的影響,併給齣瞭受慢變波包影響的能量縯變方程。研究錶明,快波過程對低鹽水糰基本沒影響,低鹽水糰從口門嚮口外東北海域運動過程中,由于水深加大,慢波過程有利于低鹽水糰髮展。
침대장강충담수확전구역저염수단현상,개전정압불은정궤제연구。기우1977년하계저염수단적연변특정분석,장초시형성적저염수단간성소우동,건립소우동방정묘술저염수단운동,채용WKBJ방법구해소우동방정,토론료쾌파과정(중력관성파)화만파과정(여류작용)대저염수단적영향,병급출료수만변파포영향적능량연변방정。연구표명,쾌파과정대저염수단기본몰영향,저염수단종구문향구외동북해역운동과정중,유우수심가대,만파과정유리우저염수단발전。
Barotropic instability mechanism analysis was carried out to research the dynamic mechanism of the low-salinity water lenses ( LSWL) in the expansion of the Changjiang diluted water ( CDW) . Based on the analysis of the LSWL’ s character in 1977 summer, the initial LSWL was taken as small disturbance, and its equation founded to describe the motion of LSWL. The solution of the equation was obtained by WKBJ method, and was used to dis-cuss the impact of the quickly varying wave ( namely inertial-gravity wave) and the slowly varying wave( namely re-sidual current) on LSWL. And the equation of energy evolution was founded, which was controlled by slowly var-ying wave packet. The main conclusion is that the quickly varying wave makes negligible influence on LSWL, but the slowly varying wave is helpful for the develop ment of LSWL because of depth increase when LSWL moves from the river mouth to the northeast.