Submit to Energies Review for Energies Propose a Special Issue

Journal Browser

► Journal Browser

Selected Papers from Sixth Annual Conference for the Development and Utilization of Deep Geothermal Energy

Special Issue Editors
Special Issue Information
Published Papers

A special issue of Energies (ISSN 1996-1073).

Deadline for manuscript submissions: closed (31 October 2017) | Viewed by 23484

Share This Special Issue

Special Issue Editors

Prof. Kewen Li

E-Mail Website
Guest Editor

School of Energy Resources, China University of Geosciences (Beijing) 29 Xueyuan Road, Beijing 100083, China
Interests: geothermal reservoir engineering; enhanced oil recovery
Special Issues, Collections and Topics in MDPI journals

Prof. Dr. Kamel Hooman

E-Mail Website
Guest Editor

Department of Process and Energy (P&E), Technische Universiteit Delft, Mekelweg 5, 2628 CD Delft, The Netherlands
Interests: melting; microchannel; carbon dioxide; acids; periodic structures; parameter design; phase change materials; cooling
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

The 6^th Annual Conference for the Development and Utilization of Geothermal Energy will be held in Beijing, China, on 26–29 March, 2017. The conference serves as a public forum for the exchange of ideas on the exploration, development, and use of geothermal resources for engineers, scientists, and managers in the geothermal industry. The conference will cooperate with national and international academic institutions, industry and government agencies to encourage economically and environmentally sound development and bring the innovative technology to China; and promote research, exploration and development of geothermal energy in ways compatible with the environment in China

Topics:

Exploration: geology, geophysics, geochemistry, heat flow studies
Drilling and well stimulation
Power generation technologies
Co-production from oil and gas fields
Enhanced Geothermal Systems (EGS)
Reservoir Engineering: injection, numerical simulation, empirical methods, tracers, etc.
Direct use: heat pumps, space heating, and cooling

Prof. Kewen Li
Assoc. Prof. Kamel Hooman
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Energies is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Published Papers (4 papers)

Download All Papers

Research

4199 KiB

Open AccessArticle

A Transient Analytical Model for Predicting Wellbore/Reservoir Temperature and Stresses during Drilling with Fluid Circulation

by Bisheng Wu, Tianle Liu, Xi Zhang, Bailin Wu, Robert G. Jeffrey and Andrew P. Bunger

Energies 2018, 11(1), 42; https://doi.org/10.3390/en11010042 - 25 Dec 2017

Cited by 18 | Viewed by 4564

Abstract

Accurate characterization of heat transfer in a wellbore during drilling, which includes fluid circulation, is important for wellbore stability analysis. In this work, a pseudo-3D model is developed to simultaneously calculate the heat exchange between the flowing fluid and the surrounding media (drill pipe and rock formation) and the in-plane thermoelastic stresses. The cold drilling fluid descends through the drill pipe at constant injection rates and returns to the ground surface via the annulus. The fluid circulation will decrease the wellbore bottom temperature and reduce the near-wellbore high compressive stress, potentially leading to tensile fracturing of the well. The governing equations for the coupled heat transfer stress problem are formulated to ensure that the most important parameters are taken into account. The wellbore is subject to a non-hydrostatic in situ far-field stress field. In modeling heat exchange between fluid and surrounding media, the heat transfer coefficients are dependent on fluid properties and flow behavior. Analytical solutions in the Laplace space are obtained for the temperatures of the fluid in both the drill pipe and annulus and for the temperature and stress changes in the formation. The numerical results in the time domain are obtained by using an efficient inversion approach. In particular, the near-well stresses are compared for the cases with fixed and time-dependent cooling wellbore conditions. This comparison indicates that the using a fixed temperature wellbore conditions may over-estimate or under-estimate the bottom-hole stress change, potentially leading to wellbore stability problems. Full article

(This article belongs to the Special Issue Selected Papers from Sixth Annual Conference for the Development and Utilization of Deep Geothermal Energy)

► Show Figures

Figure 1

1316 KiB

Open AccessArticle

Solar-Enhanced Air-Cooled Heat Exchangers for Geothermal Power Plants

by Kamel Hooman, Xiaoxue Huang and Fangming Jiang

Energies 2017, 10(10), 1676; https://doi.org/10.3390/en10101676 - 23 Oct 2017

Cited by 10 | Viewed by 3660

Abstract

This paper focuses on the optimization of a Solar-Enhanced Natural-Draft Dry-Cooling Tower (SENDDCT), originally designed by the Queensland Geothermal Energy Centre of Excellence (QGECE), as the air-cooled condenser of a geothermal power plant. The conventional method of heat transfer augmentation through fin-assisted area extension is compared with a metal foam-wrapped tube bundle. Both lead to heat-transfer enhancement, albeit at the expense of a higher pressure drop when compared to the bare tube bundle as our reference case. An optimal design is obtained through the use of a simplified analytical model and existing correlations by maximizing the heat transfer rate with a minimum pressure drop goal as the constraint. Sensitivity analysis was conducted to investigate the effect of sunroof diameter, as well as tube bundle layouts and tube spacing, on the overall performance of the system. Aiming to minimize the flow and thermal resistances for a SENDDCT, an optimum design is presented for an existing tower to be equipped with solar panels to afterheat the air leaving the heat exchanger bundles, which are arranged vertically around the tower skirt. Finally, correlations are proposed to predict the total pressure drop and heat transfer of the extended surfaces considered here. Full article

(This article belongs to the Special Issue Selected Papers from Sixth Annual Conference for the Development and Utilization of Deep Geothermal Energy)

► Show Figures

Figure 1

4415 KiB

Open AccessArticle

Enhanced Efficiency of Thermoelectric Generator by Optimizing Mechanical and Electrical Structures

by Jinlong Chen, Kewen Li, Changwei Liu, Mao Li, Youchang Lv, Lin Jia and Shanshan Jiang

Energies 2017, 10(9), 1329; https://doi.org/10.3390/en10091329 - 04 Sep 2017

Cited by 68 | Viewed by 11130

Abstract

Much attention has been paid to the application of low temperature thermal resources, especially for power generation in recent years. Most of the current commercialized thermal (including geothermal) power-generation technologies convert thermal energy to electric energy indirectly, that is, making mechanical work before producing electricity. Technology using a thermoelectric generator (TEG), however, can directly transform thermal energy into electricity through the Seebeck effect. TEG technology has many advantages such as compactness, quietness, and reliability because there are no moving parts. One of the biggest disadvantages of TEGs is the low efficiency from thermal to electric energy. For this reason, we redesigned and modified our previous 1 KW (at a temperature difference of around 120 °C) TEG system. The output power of the system was improved significantly, about 34.6% greater; the instantaneous efficiency of the TEG system could reach about 6.5%. Laboratory experiments have been conducted to measure the output power at different conditions: different connection modes between TEG modules, different mechanical structures, and different temperature differences between hot and cold sides. The TEG apparatus has been tested and the data have been presented. This kind of TEG power system can be applied in many thermal and geothermal sites with low temperature resources, including oil fields where fossil and geothermal energies are coproduced. Full article

(This article belongs to the Special Issue Selected Papers from Sixth Annual Conference for the Development and Utilization of Deep Geothermal Energy)

► Show Figures

Figure 1

12116 KiB

Open AccessArticle

A Study on the Effects of Starches on the Properties of Alkali-Activated Cement and the Potential of Starch as a Self-Degradable Additive

by Huijing Tan, Xiuhua Zheng, Limenglu Ma, Haixiao Huang and Bairu Xia

Energies 2017, 10(7), 1048; https://doi.org/10.3390/en10071048 - 20 Jul 2017

Cited by 10 | Viewed by 3467

Abstract

An urgent problem of geothermal energy source development is how to cut down the production costs. The use of temporary sealing materials can reduce the costs associated with the circulation lost by plugging, and increase the production by self-degradation. Based on the utilization of starches as self-degradable additives in the medical field, this paper investigated the effects of three kinds of starches, namely corn starch (CS), hydroxypropyl starch (HPS) and carboxymethyl starch (CMS) on the properties of alkali-activated cement (AAC). In addition, the thermal properties of starch, the compressive strength and microstructures of the cement with starch were tested, to evaluate the potentiality of starch as self-degradable additive for geothermal cement. The analysis showed that: (1) all the starches have the effect of increasing the apparent viscosity, prolonging the setting time and reducing the static fluid loss of alkali-activated cement; (2) the addition of starch increased the number of pores in 200 °C-heated cement, facilitated the leaching process, and thus promoted the self-degradation; and (3) among the three starches, CMS has the most potential as a self-degradable additive. Full article

(This article belongs to the Special Issue Selected Papers from Sixth Annual Conference for the Development and Utilization of Deep Geothermal Energy)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Selected Papers from Sixth Annual Conference for the Development and Utilization of Deep Geothermal Energy

Share This Special Issue

Special Issue Editors

Special Issue Information

Published Papers (4 papers)

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI