力学学报
力學學報
역학학보
ACTA MECHANICA SINICA
2001年
2期
205-214
,共10页
林上金%仲孝恭%成新喜%魏岗%周凯%刘宇迪
林上金%仲孝恭%成新喜%魏崗%週凱%劉宇迪
림상금%중효공%성신희%위강%주개%류우적
转环实验%斜压波热力结构%β效应%突跃区
轉環實驗%斜壓波熱力結構%β效應%突躍區
전배실험%사압파열력결구%β효응%돌약구
首次用转环实验模拟方法研究了β效应对斜压波热力结构的影响,发现β效应有抑制流动的水平混合和垂直混合的作用,使流动趋于正压;β平面上急流随高度降低而减弱,在急流的内外两侧各有一个无量纲温度值分布的突跃区,它们的空间结构与大气环流中的极锋锋区和北极锋锋区的结构相似.
首次用轉環實驗模擬方法研究瞭β效應對斜壓波熱力結構的影響,髮現β效應有抑製流動的水平混閤和垂直混閤的作用,使流動趨于正壓;β平麵上急流隨高度降低而減弱,在急流的內外兩側各有一箇無量綱溫度值分佈的突躍區,它們的空間結構與大氣環流中的極鋒鋒區和北極鋒鋒區的結構相似.
수차용전배실험모의방법연구료β효응대사압파열력결구적영향,발현β효응유억제류동적수평혼합화수직혼합적작용,사류동추우정압;β평면상급류수고도강저이감약,재급류적내외량측각유일개무량강온도치분포적돌약구,타문적공간결구여대기배류중적겁봉봉구화북겁봉봉구적결구상사.
The rotating annulus experiment is an important means in the study of rotating fluid dynamics. Geophysical fluid flows includes the atmosphere circulation. The generation, development and dynamics of the baroclinic can be simulated by rotating fluid annulus experiment.Therefor, the dynamic of the large scale quasi-geostrophic of atmosphere and ocean can be understand more deeply.
The β effect is an important factor acting on the geophysical fluid flow. But there is no general accepted point of view in the important the β effect. There are two points of view to characters of atmospheric long wave, i.e., The one based on the classical theory, the other newer point of view believes that it is not the Rossby wave, but just a barolinic wave influenced by the β effect.
An experiment study about the β effect action on the baroclinic wave in an rotating annulus is outlined in this paper. The quantization measures of temperature field of fluid flow in the rotating annulus has been accomplishes and the qualitative analysis about the inner thermal structure of the flow that acted by theβ effect is accomplished. The equipment of the experiment is a rotating annulus in which the inner wall and outer wall are kept at low and high temperature by a temperature control. The inner temperature of the flow is detected by the thermodetector with three dimensional fine grid.
Comparing a group of the inner thermal structure of same surface flow pattern on the f plane and the β effect plane, the following results have been gotten in this paper.
(1) On the f plane, the fluid flow are obviously. The fluid flow can be divide two part: the bigger one near the outer wall is in static stable, and the inner fluid is in static instability. It is somewhat different from Fulty[s] which showed that the baroclinic flowing in the rotating annulusis in static stability.
(2) On the β plane, owing to the β effect inhibit the horizontal mixing and the vertical mixing,the fluid, flow tend to barotrtopy. The stratification curve of the azimuth mean temperature on the radial fixed point shows that the fluid flow on the β plane is stable. The jet flow in the rotating annulus corresponding to the westen lies of the atmosphere is gradually strengthened from the bottom to the top. This is identical to the western lies of the really atmosphere. There are two isotherm ribbon on the inner side and outer side of the jet flow in each height spacing horizontal temperature distribution chart. The width between the two isotherm ribbons is gradually reduces from the low level to the high level, from the bottom to the top. The radial points of the isotherm ribbon to the cold wall. There are two temperature catastrophe regions, on the inner side and outer side of jet flow, corresponding to the two isotherm ribbons in the horizontal temperature distribution chart and in the azimuth mean temperature distribution chart. The inner and outer catastrophe region corresponds to the arctic front and polar front, respectively.
The experiment show that the thermal feature of the baroclinic is changed by the β effect,the atmospheric long wave is Rossby wave. The results of the paper show that the β effect is very important to the quasi-geostrophic flow, such as the atmospheric circulation.