التفاصيل البيبلوغرافية
| العنوان: |
Influence of asperities on fluid and thermal flow in a fracture: a coupled Lattice Boltzmann study, submitted to JGR |
| المؤلفون: |
A. Neuville E. G. Flekkøy |
| المساهمون: |
The Pennsylvania State University CiteSeerX Archives |
| المصدر: |
http://arxiv.org/pdf/1307.1286.pdfTest. |
| بيانات النشر: |
B |
| سنة النشر: |
2013 |
| المجموعة: |
CiteSeerX |
| الوصف: |
and R. Toussaint2,3 Abstract. The characteristics of the hydro-thermal flow which occurs when a cold fluid is injected into a hot fractured bedrock depend on the morphology of the fracture. We consider a sharp triangular asperity, invariant in one direction, perturbing an otherwise flat fracture. We investigate its influence on the macroscopic hydraulic transmissivity and heat transfer efficiency, at fixed low Reynolds number. In this study, numerical simula-tions are done with a coupled lattice Boltzmann method that solves both the complete Navier-Stokes and advection-diffusion equations in three dimensions. The results are com-pared with those obtained under lubrication approximations which rely on many hypothe-ses and neglect the three-dimensional (3D) effects. The lubrication results are obtained by analytically solving the Stokes equation and a two-dimensional (integrated over the thickness) advection-diffusion equation. We use a lattice Boltzmann method with a dou-ble distribution (for mass and energy transport) on hypercubic and cubic lattices. Be-yond some critical slope for the boundaries, the velocity profile is observed to be far from a quadratic profile in the vicinity of the sharp asperity: the fluid within the triangular asperity is quasi-static. We find that taking account of both the 3D effects and the cool-ing of the rock, are important for the thermal exchange. Neglecting these effects with lubrication approximations results in overestimating the heat exchange efficiency. The evolution of the temperature over time, towards steady state, also shows complex be-havior: some sites alternately reheat and cool down several times, making it difficult to forecast the extracted heat. 1. |
| نوع الوثيقة: |
text |
| وصف الملف: |
application/pdf |
| اللغة: |
English |
| العلاقة: |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.745.8087Test; http://arxiv.org/pdf/1307.1286.pdfTest |
| الإتاحة: |
http://arxiv.org/pdf/1307.1286.pdfTest |
| حقوق: |
Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
| رقم الانضمام: |
edsbas.920A631B |
| قاعدة البيانات: |
BASE |
