Finally , the two dimensional flow in the diffuser is calculated , the results show that the change of ma makes an effect to the performance of the diffuser . owing to the accretion of ma , the action of oblique shock waves and the boundary layer pricks up , the flow separates from the wall where the shock waves impinge on the boundary layer more quickly , the cluster of diamond shock waves becomes larger . moreover , by comparing the change of flow field under different structure parameter , it is found that the augment of length of constant area section alter the structure of fluid field little , a smaller area ratio and larger angle of compression section make the diffuser working better 最后,針對擴壓器中的二維流場進行了數(shù)值模擬,結(jié)果表明馬赫數(shù)對擴壓器性能影響較大,隨著馬赫數(shù)的增大,擴壓器管道內(nèi)激波-附面層干擾加劇,流動從附面層分離相應(yīng)加劇,激波串數(shù)目增多;通過比較不同結(jié)構(gòu)參數(shù)下的擴壓器內(nèi)流場,發(fā)現(xiàn)等直段長度的變化幾乎沒有改變流場結(jié)構(gòu),只是對局部流場稍有影響,并且在其它參數(shù)不變的情況下,一定范圍內(nèi)減小面積比a2 / a1和增大收縮角有利于擴壓器性能的提高。
The systematical experimental study on the structure characteristic of soft clay from wenzhou has been carried out . based on schmermann and nagaraj ' s experimental conclusions and a large number of structure characteristic experiments of soft clay from wenzhou , an updated correction method of compression curve of disturbed soil is presented . the corrected compression curve is composed of four sections : horizontal section , elastic compression section , structure dilapidation compression section and normal compression section 結(jié)合溫州軟土進行了結(jié)構(gòu)性試驗,對軟土的結(jié)構(gòu)性進行了系統(tǒng)研究,在schmertmann和nagaraj等人實驗結(jié)論及大量溫州軟土結(jié)構(gòu)性試驗的基礎(chǔ)上,得到了結(jié)構(gòu)性軟土的四段式壓縮曲線:水平段、彈性壓縮段、結(jié)構(gòu)破損突降段,正常壓縮段。