Experimental study of convective heat transfer characteristics of fractures with different morphologies based on fractal theory

Bibliographic Details
Title: Experimental study of convective heat transfer characteristics of fractures with different morphologies based on fractal theory
Authors: Peng Zhang, Yanjun Zhang, Yibin Huang
Source: Case Studies in Thermal Engineering, Vol 28, Iss , Pp 101499- (2021)
Publisher Information: Elsevier, 2021.
Publication Year: 2021
Collection: LCC:Engineering (General). Civil engineering (General)
Subject Terms: Enhanced geothermal system(EGS), Hot dry rock (HDR), Heat transfer, Overall heat transfer coefficient (OHTC), Fractal theory, Engineering (General). Civil engineering (General), TA1-2040
More Details: In the Enhanced Geothermal System (EGS), the flow state of the fracture of the thermal reservoir (granite) is important for heat transfer. In this paper, the effects of reservoir temperature, flow rate and fracture shape on the thermal convection that occurs in the fracture of rough granite are studied based on the fractal dimension theory. The rough fracture is manufactured regularly by carving technology. The shear flow experiments were carried out at confining pressures of 10, 15 and 20 MPa to analyze the flow state. The convective heat transfer experiments were conducted at 60 and 70 °C to simulate different heat reservoir conditions. The results indicated that the outlet temperature and overall heat transfer coefficient (OHTC) increased with the increase in the rock temperature. A higher flow rate can enhance the thermal performance. The complexity of the fracture surface is also an important factor that affects the convective heat transfer process. The larger fractal dimension of the fracture surface can more easily excite turbulence, affecting the thickness of the boundary layer. The OHTC will increase as the fractal dimension increases.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 2214-157X
Relation: http://www.sciencedirect.com/science/article/pii/S2214157X21006626; https://doaj.org/toc/2214-157X
DOI: 10.1016/j.csite.2021.101499
Access URL: https://doaj.org/article/be4ea8953d524119b5516fa0877fda47
Accession Number: edsdoj.be4ea8953d524119b5516fa0877fda47
Database: Directory of Open Access Journals
More Details
ISSN:2214157X
DOI:10.1016/j.csite.2021.101499
Published in:Case Studies in Thermal Engineering
Language:English