基于高階譜元與剛性浸入耦合的數(shù)值分析方法與突涌水模擬研究.pdf

1、At present, a large number of national infrastructures such as traffic, waterconservancy and hydropower were built in western mountainous areas and karst areaswith extremely complicated topographical conditions and geolo

2、gical settings.In theprocess of construction, many kinds of geological disasters are likely to occur.Amongthem, water inrush was one of the most serious geological disasters in engineeringconstruction.80％ of major safety

3、 disasters were caused by water inrush during thetunnel excavation in China.The casualties and property losses caused by water inrushwere more than caused by other geologic hazards.And it is also made serious concernto p

4、ublic.Because water inrush has the natures of suddenness and diversity, the disastermechanism is very complex.It is difficult to understand the process of water inrushthrough the existing programs.
　　The disaster-caus

5、ing mechanism of water inrush was studied based on water inrushtypes.Several typical water inrush were investigated through the IB-SEM system.
　　(1) Water inrush types is divided into two major categories and six mino

6、r groups.
　　The two major categories are water inrush through filling structures and water inrushthrough the destruction of water resisting rock mass structure.Each category includethree models.The first category incl

7、udes direct water inrush, slip water inrush andpiping water inrush respectively.The second category includes direct water inrush, keyblock water inrush and splitting water inrush respectively.
　　(2) The finite element

8、 method of Semtex was used in this study which is thespectral/hp element method.The spectral/hp element method is a combination of finiteelement method and traditional spectral element method.It has not only the geometri

9、calflexibility of the finite element method, but also the high accuracy of the spectralelement method.Comparing with the low order finite method such as the finite elementmethod, the finite volume method and the finite d

10、ifference method, the spectral/hpelement method is more efficient and less error to obtain an approximate solution forsufficiently problems.The spectral/hp element method has the following maincharacters:
　　① The shap

11、e function was used in the spectral/hp element method, which basedon the orthogonal polynomial.The spectral accuracy of each element is obtained byusing the Lagrange interpolation method.
　　② Comparing with the tradit

12、ional gauss integral method, the quick tensorintegration is used in the spectral/hp element method.Its characteristic is that it canguarantee the integral efficiency and also evaluate the validity of the elementintegrati

13、on.
　?、?The unstructured grid is used to ensure the efficiency of computation andreduce the resource occupied by runtime.
　　(3) The interaction between particles and fluid was investigated by the rigidimmersed boun

14、dary method.The accuracy of this method was verified based on thecomputed results with the traditional body-fitted mesh in numerical simulation of theflow through the cylinder.Then the governing equations of particles mo

15、tion and contactin fluid are constructed.The movement of the particles and the interaction between thefluid and the particles are investigated.This method avoided the problem of lowcomputational efficiency and error caus

16、ed by the re-division of the grid when the solidsmoved.Finally, the movement simulation of multi particles in the fluid was carried out,which can provide a completely new numerical simulation method.
　　(4) In the firs

17、t category of water inrush through filling structures, the interactionof particles-fluid and particles-particles were studied.Then the direct water inrush wasinvestigated by the IB-SEM system.The slices method was modifi

18、ed and applied intothe slip water inrush research.The strip analytical calculation model of fillings wasbuilt.The calculating equation of the minimum safe thickness was deduced by the forcebalance condition.A new enginee

19、ring practical analytical method was formed.Finallya new numerical method for the realization of skeleton particles and fine particles wasused by IB-SEM system, which simulated the whole process from the formation ofseep

20、age channel to the water inrush.
　　(5) Based on Semtex simulation, the influence of different fracture width on theflow distribution under different Reynolds number was investigated.The instabilitymechanism of key blo

21、ck water inrush was researched through the force analysis ofwater resisting block.Then the key block water inrush was investigated by the IB-SEMsystem.Finally, according to the fracture theory, three different types of h

22、ydraulicfracturing were considered.
　　(6) Based on the Fourier transformation and 3D immersed boundary method, the3D IB-SEM system was established.Then using the open MPI and Hamilton HPCservice, computing efficiency

23、has greatly increased.The three dimensional pore flowwas successfully investigated.
　　(7) In the water inrush risk assessment, an attribute recognition model of waterinrush risk evaluation was established based on att