Thermal Science and Engineering Progress最新文献

{"title":"Improving thermal environment and ventilation efficiency in high-temperature excavation tunnels via an innovative heat insulation and cooling baffle","authors":"Yu Xu ,&nbsp;Zijun Li ,&nbsp;Junjian Wang ,&nbsp;Yibin Lu ,&nbsp;Zi Cheng ,&nbsp;Jingkai Wang ,&nbsp;Zhang Lin","doi":"10.1016/j.tsep.2024.102992","DOIUrl":"10.1016/j.tsep.2024.102992","url":null,"abstract":"<div><div>An increasing number of tunnels inevitably encounter high-temperature environments induced by elevated geotemperatures. The energy demand for ventilation and cooling in excavation tunnels increases significantly as the temperature of the surrounding rock increases, thereby hindering the sustainable exploitation of deep resources. This paper presents an optimization method for airflow organization in excavation tunnels that integrates thermal insulation and cooling (TIC) baffles. The proposed approach significantly improves the cooling effect of the auxiliary ventilation system while reducing energy consumption. This method offers the advantages of simplicity, convenience, and cost-effectiveness. A multifield coupling model using COMSOL software was developed and validated to analyze the system, and the application scenario was explored. Several ventilation scenarios were examined, highlighting that TIC baffles effectively reduce the heat release from the surrounding rock and lower the airflow temperature in personnel areas in the excavation tunnel. By implementing TIC baffles, the average airflow temperature in the excavation tunnel decreases by 1.5 °C to 1.8 °C, resulting in a saving of approximately 5.11 kW in cooling energy. Increasing the circulating water flow in the heat-exchange pipe of the TIC baffles or reducing the initial circulating water temperature can enhance the cooling capacity of the TIC baffles and lower the tunnel airflow temperature to a certain extent. The distance between the TIC baffles and surrounding rock significantly affects the airflow temperature between the left and right TIC baffles. An excessive length of TIC baffles (L &gt; 7 m) leads to heat accumulation and high-temperature airflow in localized areas. In This study, a method for optimizing the thermal environment and saving energy in high-temperature excavation tunnels is proposed.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"55 ","pages":"Article 102992"},"PeriodicalIF":5.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142658041","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing thermal performance and reducing entropy generation rate in evacuated tube solar air heaters with inserted baffle plate using static mixers: A CFD-RSM analysis","authors":"Moslem Abrofarakh,&nbsp;Hamid Moghadam","doi":"10.1016/j.tsep.2024.103012","DOIUrl":"10.1016/j.tsep.2024.103012","url":null,"abstract":"<div><div>Evacuated tube collector solar air heaters with an inserted baffle (ETCSAH-IB) have gained attention due to their applicability in various applications and their use of solar energy for clean and sustainable heating. In this study, the effect of incorporating a static mixer (SM) into the ETCSAH-IB (ETCSAH-IBSM) on thermal performance and entropy generation rate (EGR) was investigated using computational fluid dynamics (CFD) and Response Surface Methodology (RSM) approaches (CFD-RSM), with the aim of device performance enhancement. The twist angle and blade thickness were considered as characteristic parameters of the static mixer. The study investigated the thermal performance and EGR of the ETCSAH-IBSM with variations in Reynolds numbers, SM twist angles, and SM blade thicknesses. The results demonstrated that thermal performance and total EGR of the ETCSAH-IBSM increased with Reynolds number, twist angles, and blade thickness of the SM. Additionally, under maximum conditions, the thermal performance of the ETCSAH-IBSM exceeded that of the ETCSAH-IB by 490 %. Furthermore, integrating the SM into the ETCSAH-IB resulted in a notable 77 % reduction in total EGR. These results were obtained only by a pressure drop of about 140 Pa. Achieving these results by embedding a static mixer inside the ETCSAH-IB is presented as the novelty of this study. Finally, optimization was carried out using RSM to maximize thermal performance and minimize pressure drop of the ETCSAH-IBSM. The optimized values suggested a Reynolds number near 10000, a blade thickness near 4 mm, and a twist angle of 60 degrees.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"55 ","pages":"Article 103012"},"PeriodicalIF":5.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142658111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Formulating iron ore pellet induration process in an industrial straight grate system: Real-time experimentation and validation","authors":"Satyanarayana Lalam ,&nbsp;Amiya K Jana ,&nbsp;Srinivas Dwarapudi","doi":"10.1016/j.tsep.2024.102928","DOIUrl":"10.1016/j.tsep.2024.102928","url":null,"abstract":"<div><div>Understanding the complex process of iron ore pellet induration is crucial in a straight grate system in the steelmaking industry. There is no attempt made so far to predict the behavior of this unit considering the physiochemical processes (drying, carbon combustion and limestone calcination) along with the heat transfer within the pellet, and between the hot gas and pellet. Moreover, the reported models are validated mainly with the pot test data. To address these research gaps, in this contribution, a rigorous model framework is proposed for an industrial induration unit considering all these above-mentioned issues together with some other practical aspects, including the heat transfer from hot gas to grate bar and heat loss due to air leakage into the system. To validate this rigorous formulation, attempt is further made to perform the real-time experimentation with induration system equipped with a thermocar. It is shown first time that the predicted temperature profiles of the pellets, grate bar and exit gas associated with the running bed are consistent with the plant data. The fuel consumption data is further obtained to investigate the performance of the proposed formulation at different operating regimes. It is observed that the mean absolute percentage error (MAPE) between the measured and predicted fuel rates is reasonably low (i.e., 4.2%). With this, it is recommended to use the proposed formulation for online property prediction, process design, optimization, troubleshooting, control and scale-up of the induration unit.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"55 ","pages":"Article 102928"},"PeriodicalIF":5.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142356834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A new simulation approach of air source heat pump adopting the holistic process distributed parameter method and hybrid PID-bisection control algorithm","authors":"Wenquan Hu ,&nbsp;Guangcai Gong ,&nbsp;Xiang Chen ,&nbsp;Pei Peng ,&nbsp;Xiwen Huang ,&nbsp;Fuyu Zhou ,&nbsp;Bolin Li ,&nbsp;Riming Liu ,&nbsp;Bin Qin","doi":"10.1016/j.tsep.2024.102957","DOIUrl":"10.1016/j.tsep.2024.102957","url":null,"abstract":"<div><div>Air source heat pump (ASHP) faces problems of performance deterioration when operating at low ambient temperature due to the low compression ratio, high discharge temperature, frost accumulation, etc., and may even become nonfunctional at sub-zero-centigrade ambient temperature, requiring attention and tools for studying. This paper proposed a kind of holistic process distributed parameter simulation approach of ASHP system adopting the hybrid PID-bisection (PID: proportional-integral-derivative) control algorithm. Main components of the ASHP are modeled with the distributed parameter method. An adiabatic compression model of two-phase fluid based on thermodynamics is proposed. The PID-bisection control algorithm and variable speed integral PID &amp; bisection control algorithm are proposed and applied to iterative computation of the model. A single/two-stage compression ASHP with an intercooler is simulated by this approach. The average deviation of simulation results of the model from experimental data is not more than 7 %, and the maximum deviation is not more than 18 %. For simulation of single-stage compression mode, the maximum error is not more than 4%. For simulation of two-stage compression mode under low-evaporating-temperature operating conditions, the maximum error is not more than 4 %. Computational speed of the ASHP model is significantly improved by using the PID-bisection control algorithm, and could be further accelerated by using the variable speed integral PID &amp; bisection control algorithm. The proposed simulation approach is not only effective in sophisticated simulation of performance of single-stage and two-stage compression ASHP, but also potential for research on the optimization of the ASHP in cold regions.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"55 ","pages":"Article 102957"},"PeriodicalIF":5.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142427875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heat transfer enhancement in pressurized solar cavity receivers with densely packed metallic wire mesh","authors":"Sayuj Sasidharan,&nbsp;Pradip Dutta","doi":"10.1016/j.tsep.2024.102964","DOIUrl":"10.1016/j.tsep.2024.102964","url":null,"abstract":"<div><div>Pressurized solar receivers are promising candidates as heat sources for integration with high-efficiency closed-loop air and supercritical carbon-dioxide based Brayton cycles. This paper focuses on the heat transfer enhancement of such a solar receiver using inline stacked wire mesh fibers in the heat transfer fluid flow path. The study involves modelling, characterization, and performance evaluation of a cavity-receiver with densely packed wire meshes. A new experimentally validated hybrid numerical approach is presented for modelling the inline stacked wire mesh layers. Initially, a direct numerical simulation at the pore scale on a representative elementary volume (REV) of the wire mesh geometry is performed for determining the hydrodynamic and thermal characteristics of the medium. Subsequently, these hydrodynamic and thermal properties are used to define a volume-averaged macroscopic porous medium. Experiments are performed using a rectangular channel stacked with stainless steel wire meshes, heated using a plate heater, and pressurized air supplied using a reciprocating compressor. Both numerical and experimental studies are performed for a Reynolds number range of 28 to 213 resulting in a Nusselt number range of 7.2 to 213. The porous medium model predictions for pressure gradient are within 17 %, while predictions for outlet air temperature are within 5 % of the experimentally obtained values. The study predicts a maximum heat transfer enhancement of five times in a channel stacked with wire meshes compared to the case of a clear channel, but incurring a peak pressure drop of only about 1.1 kPa.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"55 ","pages":"Article 102964"},"PeriodicalIF":5.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142427881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal management and power generation characteristics in a bifurcating channel by using a piezo-embedded inclined elastic fin assembly during turbulent forced convection of ternary nanofluid","authors":"Fatih Selimefendigil ,&nbsp;Hakan F. Oztop","doi":"10.1016/j.tsep.2024.102887","DOIUrl":"10.1016/j.tsep.2024.102887","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Numerous engineering systems use piezoelectric energy harvesters (PE-EHs), which have several benefits including low cost, simplicity, better power density, and ease of installation. They can be used in different applications for energy harvesting and different external sources such as wind and vortex induced vibrations due to fluid–structure interaction can be utilized. This study uses a unique elastic fin PE/EH assembly for power generation, thermal management, and flow control in a bifurcating channel. Performance of the system is improved by using ternary nanofluid in the channel cooling system. Galerkin weighted residual FEM with ALE is used as the solution method. The convective heat transfer performance and power generation by the EH device are investigated in relation to the varying following parameters: Reynolds number (Re between 10000 and 30000), PE-EH inclination (&lt;span&gt;&lt;math&gt;&lt;mi&gt;γ&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt; between 0 and 60), fin horizontal location (&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;x&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;f&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; between &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mi&gt;H&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;mi&gt;H&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;), and nanoparticle loading in the base fluid (&lt;span&gt;&lt;math&gt;&lt;mi&gt;ϕ&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt; between 0 and 0.03). The vortex size and distribution near the junction are significantly influenced by the fin inclination and horizontal location of the fin assembly within the bifurcating channel. When varying other parameters of interest, using nanofluid at the highest loading results in significant deflection of the fin assembly and power generation within the PE-EH. Enhancement factors (EFs) for power generation becomes 15.6 and 39.8 when cases of lowest and highest Re are compared with pure fluid and nanofluid while they are 2.93 and 3.38 for thermal performance improvements. Fin inclination of &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;γ&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;30&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; is found as the optimum inclination for achieving the highest power from the assembly. Higher inclination of elastic fin/PE-EH assembly results in cooling performance deterioration while average Nu reduces by a factor of 2.94 by varying inclination from &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;γ&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;30&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; to &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;γ&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;60&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; with nanofluid. For power generation, effects of using nanofluid with varying inclination is significant and EF becomes 252 from &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;γ&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; to &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;γ&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;30&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;. There are opposing tendencies for the device’s power generation and cooling performance enhancement when the fin’s horizontal placement is changed. EF for average Nu is 7.25 for varying fin location. As the loading of nanoparticle inside the base fluid increases, the average Nu and generated power exhibit non-linear rising characteristics. Polynomial type correlations are provided for t","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"55 ","pages":"Article 102887"},"PeriodicalIF":5.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142445731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal modeling and its role in management of bifurcation aneurysms and associated ischemic complications in the middle cerebral artery","authors":"Tengyun Guo ,&nbsp;Xiaoshu Wang ,&nbsp;Shixin Peng,&nbsp;Yulong Qiu,&nbsp;Ji Zhu,&nbsp;Xiaodong Zhang,&nbsp;Rui Xu","doi":"10.1016/j.tsep.2024.102985","DOIUrl":"10.1016/j.tsep.2024.102985","url":null,"abstract":"<div><div>Bifurcated aneurysm of cerebral artery is a common cerebrovascular disease, which can easily lead to serious ischemic complications. Traditional treatments face challenges of risk and effectiveness. Therefore, it is particularly important to explore new therapeutic strategies. In recent years, the application of thermal modeling techniques in medical biological systems has provided a new perspective for the analysis of hemodynamics and tissue thermal response. The purpose of this study was to investigate the role of heat model in the treatment of bifurcated cerebral artery aneurysms and their associated ischemic complications, and to evaluate its potential value in understanding disease mechanisms and optimizing treatment protocols. In this study, a three-dimensional thermal model was used to simulate the heat conduction and blood flow characteristics of the bifurcated parts of cerebral arteries. Combined with the clinical data of patients, the influence of the thermal model on the formation mechanism of aneurysms and the prognosis evaluation of ischemic complications were analyzed through numerical calculation and experimental verification. Compare the performance of different treatment methods in thermal models. The thermal model shows that the temperature distribution at the aneurysm site is closely related to the blood flow velocity, and the local temperature increase may promote thrombosis and lead to ischemic complications. The treatment regimen optimized by the thermal model showed significant improvement in the simulation, reducing the risk of complications and improving hemodynamic parameters. Heat model can reveal the dynamic relationship between blood flow and temperature in the study of cerebral artery bifurcation aneurysm, and provide theoretical support for clinical treatment.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"55 ","pages":"Article 102985"},"PeriodicalIF":5.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142533748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A review on flexible peak shaving development of coal-fired boilers in China under the carbon peak and carbon neutrality goals","authors":"Jiaye Xu,&nbsp;Qichao Zhang,&nbsp;Nina Ye,&nbsp;Zhongxiao Zhang,&nbsp;Xiaojiang Wu,&nbsp;Haojie Fan","doi":"10.1016/j.tsep.2024.103004","DOIUrl":"10.1016/j.tsep.2024.103004","url":null,"abstract":"<div><div>The flexible peak shaving capacity of coal-fired power units has a direct impact on the trajectory of renewable energy in China’s evolving energy landscape, and therefore, the achievement of carbon peak and carbon neutrality goals. In this paper, the concept of flexible peak shaving is delineated. The developmental status of flexible peak shaving in China is introduced, and the challenges of flexible boiler peak shaving are summarised. The genesis, principles, efficacy, advantages, and limitations of three technologies, namely, thermo-hydrodynamic system optimisation, external energy storage system configuration, and control system optimisation, are elaborated. Ongoing research is summarised, and the leading teams in China are highlighted. This review describes five demonstration projects undertaken in China and explains policy support and compensation mechanisms. It is found that flexible peak shaving can be achieved by combining deep and fast peak shaving. The fast peak shaving capacity of China’s coal-fired boilers is insufficient, and the primary challenge is the lack of energy supply capacity. For fast peak shaving, external energy storage system configuration techniques such as Ruths steam storage and molten salt thermal energy storage are more appropriate. To improve the enthusiasm for fast peak shaving of coal-fired power units, a national compensation mechanism should be implemented in China.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"55 ","pages":"Article 103004"},"PeriodicalIF":5.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142658080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of porous media on heat transfer of hydrocarbon fuel in the regenerative cooling channel under different heating surfaces","authors":"Yongqian Xie,&nbsp;Hao Liu,&nbsp;Hui Shi,&nbsp;Xingzhen Zhu,&nbsp;Yulei Guan","doi":"10.1016/j.tsep.2024.103014","DOIUrl":"10.1016/j.tsep.2024.103014","url":null,"abstract":"<div><div>The regenerative cooling technology which uses endothermic hydrocarbon fuel as coolant provides guarantee for the efficient operation of scramjet. The porous medium used in the regenerative cooling channel can enhance heat transfer to increase the heat sink of hydrocarbons due to its high thermal conductivity. To further elucidate the effect of porous media in the actual regenerative cooling, this paper constructs a three-dimensional cooling channel filled with porous media under different heating surfaces in the numerical simulations. The simulation results show that the buoyancy of fuel fluid under different heating surfaces is different, causing different behavior of the fluid flow direction on the cross section. Bottom heating produces the best heat transfer effect in the regenerative cooling channels with/without porous media. When porous medium is added in the cooling channel, its high thermal conductivity is conducive to energy transport, leading to the reduction of the density stratification and temperature non-uniformity coefficient, and the outlet temperature and heat sink of fuel fluid are increased. In addition, the obstructing effect of porous media causes the cross-sectional fluid flow direction to change in the cooling channel, and the most significant obstruction is observed in the case of the top heating process.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"55 ","pages":"Article 103014"},"PeriodicalIF":5.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142658112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental research on the heat balance of independent heat extraction-release double helix energy pile","authors":"Ziming Liao,&nbsp;Guangqin Huang,&nbsp;Chunlong Zhuang,&nbsp;Hongyu Zhang,&nbsp;Lei Cheng,&nbsp;Fei Gan","doi":"10.1016/j.tsep.2024.103009","DOIUrl":"10.1016/j.tsep.2024.103009","url":null,"abstract":"<div><div>The use of spiral buried pipe of ground source heat pump in civil defense engineering shows great potential, exploring its complex heat transfer features and thermal balance through experimental approaches is essential. This paper utilizes an independent heat extraction-release double helix energy pile to manage condensation heat discharge in underground projects. An experimental platform was established to compare three scenarios: pure heat release, centralized heat extraction, and uniform heat extraction. The pure heat release mode resulted in substantial soil heat accumulation, whereas the centralized heat extraction and uniform heat extraction demonstrated significant reductions in average temperature rise, with decreases of 24.7 % and 31.3 % near the buried pipes, and 27.3 % and 46.3 % in the central regions. The heat-extracting pipe under centralized heat extraction and uniform heat extraction conditions remove 18.7 MJ and 20.3 MJ of accumulated heat, amounting to 10.3 % and 11.2 % of the total heat dissipation, respectively, effectively mitigating the thermal accumulation in the soil during operation. Besides, the outlet temperature of the heat-extracting pipe is predominantly influenced by the highest temperature in the heat exchange zone, lowering the inlet temperature effectively increases the temperature difference between the inlet and outlet, enhancing the amount of heat removed. The accumulation of underground heat can enhance the heat extraction performance of the pipes, and increasing the water flow rate of the heat-releasing pipe positively impacts the heat extraction capacity. After soil temperatures rise, running the heat-extracting pipe with cooler inlet water and a moderately higher flow rate is advised for extracting the accumulated heat.</div></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":"55 ","pages":"Article 103009"},"PeriodicalIF":5.1,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142658106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}