Numerical study on airflow temperature field in a high-temperature tunnel with insulation layer

Kang, Fangchao; Li, Yingchun; Tang, Chun’an

doi:10.1016/j.applthermaleng.2020.115654

Cited by 77 publications

(28 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The thermophysical parameters of the surrounding rock matrix of the simulated single-fracture tunnel are shown in Tables 3 and 4. The relevant parameters are from the literature (Kang et al 2020).…”

Section: Calculation Parametersmentioning

confidence: 99%

A fully coupled seepage–heat transfer model including a dynamic heat transfer coefficient in fractured rock sample with a single fissure

Zhang

Wang

Yang

et al. 2021

Geomatics, Natural Hazards and Risk

View full text Add to dashboard Cite

Conventional seepage-heat transfer models in simulating the heat transfer between fluid and rock in fractures mainly involve one-way coupling and do not consider the influence of temperature on the seepage. Moreover, it is an enormous challenge to define parameters of the explicit heat transfer between the rock and fluid. In order to resolve these shortcomings, a two-way fully coupled model of the seepage-heat transfer in the fractured rock was established in the present study. Based on the original geometric structure of the experimental device, combined with the actual engineering scale, the local dynamic heat transfer coefficient of the fractured rock was established, which is related to the fracture aperture, flow velocity and thermal parameters. Then, the proposed model was verified through the experiment and excellent agreement was achieved in this regard. It was found that the dynamic heat transfer coefficient changes the temperature distribution of fluid and rock in the original static heat transfer coefficient fracture system. The proposed model simplifies the parameters required for the calculation of the heat transfer coefficient. These parameters are related to characteristic variables, such as velocity and rock temperature, and can be simply obtained from standard laboratory tests.

show abstract

Section: Calculation Parametersmentioning

confidence: 99%

A fully coupled seepage–heat transfer model including a dynamic heat transfer coefficient in fractured rock sample with a single fissure

Zhang

Wang

Yang

et al. 2021

Geomatics, Natural Hazards and Risk

View full text Add to dashboard Cite

show abstract

“…Since EGS-E engineering in depths is to be under high temperature environment, for the sake of achieving eligible working temperature for personnel and equipment, it should be necessary to take the initiative in cooling down the surrounding. According to the latest relevant study [22], it was found that at the entrance the heat exchange from surrounding rocks to inside tunnel airflow is the most intense. Due to the largest temperature difference between the tunnel wall and surrounding rock, there is taken as the research objective.…”

Section: Temperature Distribution and Stress Field In Egs-e Tunnel After Ventilation Coolingmentioning

confidence: 99%

“…As shown in Table 3 are the thermophysical parameters of granite as the surrounding rock [58] and the material made of manufacturing thermal insulation liner [22], respectively. On the other hand, the mechanical parameters of CWFS model had been shown in Table 2.…”

Section: Temperature Distribution and Stress Field In Egs-e Tunnel After Ventilation Coolingmentioning

confidence: 99%

“…For the former, many researchers studied the stress redistribution and damage extent of surrounding rock due to excavation by relying on empirical approach [17], numerical simulation [18,19] and theoretical calculation [20]. For the latter, relevant studies focused on the temperature evolution of surrounding rock [21], effective ventilation distance [22] and heat insulation [23] in tunnel ventilation. However, due to the temperature of the non-geothermal mining tunnel is not high (usually less than 80 • C), previous researches mostly studied the characteristic factors of deep engineering separately and independently.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Numerical Study on Damage Zones Induced by Excavation and Ventilation in a High-Temperature Tunnel at Depth

Zhu

et al. 2021

Energies

View full text Add to dashboard Cite

Geothermal power is being regarded as depending on techniques derived from hydrocarbon production in worldwide current strategy. However, it has artificially been developed far less than its natural potentials due to technical restrictions. This paper introduces the Enhanced Geothermal System based on Excavation (EGS-E), which is an innovative scheme of geothermal energy extraction. Then, based on cohesion-weakening-friction-strengthening model (CWFS) and literature investigation of granite test at high temperature, the initiation, propagation of excavation damaged zones (EDZs) under unloading and the EDZs scale in EGS-E closed to hydrostatic pressure state is studied. Finally, we have a discussion about the further evolution of surrounding rock stress and EDZs during ventilation is studied by thermal-mechanical coupling. The results show that the influence of high temperature damage on the mechanical parameters of granite should be considered; Lateral pressure coefficient affects the fracture morphology and scale of tunnel surrounding rock, and EDZs area is larger when the lateral pressure coefficient is 1.0 or 1.2; Ventilation of high temperature and high in-situ stress tunnel have a significant effect on the EDZs scale; Additional tensile stress is generated in the shallow of tunnel surrounding rock, and the compressive stress concentration transfers to the deep. EDZs experiences three expansion stages of slow, rapid and deceleration with cooling time, and the thermal insulation layer prolongs the slow growth stage.

show abstract

“…In theory, two approaches can be used to reduce the damage of high-temperature tunnels subjected to the earthquake (Tsinidis et al, 2020;Zhao et al, 2018). One is the design of thermal insulation and shock absorption, which is to reduce the energy when an earthquake occurs through the thermal insulation layer, and prevent the high temperature of surrounding rock from transferring to the secondary lining structure (Kang et al, 2020;Suzuki et al). The second is the reinforcement of structure and surrounding rock, which is to reduce the tunnel damage of thermal seismic coupling by appropriately improving the stiffness, toughness, and crack resistance of lining and surrounding rock (Cui & Ma, 2021b;Jamshidi Avanaki, 2019).…”

Section: Introductionmentioning

confidence: 99%

Application of thermal insulation layer in the tunnel with high temperature subjected to strong seismic motion

Cui

2021

All Earth

View full text Add to dashboard Cite

Tunnels with high-temperature rocks are built in seismically active areas, which may suffer heavy damages in earthquakes. This paper aims to explore the thermal insulation effect and seismic isolation effect layer of the thermal insulation layer in high-temperature tunnels. Firstly, taking Jiwoxiga tunnel in Tibet, China as the research background, the finite difference models are established to investigate temperature fields, seismic response, and structural safety of the tunnel. Then, the two most commonly used insulation layers are applied to the support structure to study the thermal insulation effect and seismic isolation effect of the layers. Besides, the effect of factors including the thickness, elastic modulus, surrounding rock, and boundary temperature on the application of the layer are investigated in detail. The result shows that the application of the thermal insulation layer has isolated the geothermal and seismic motion propagating from the rock to linings, thus improving the structural safety of the high-temperature tunnel when encountering strong earthquakes. The thermal insulation effect of the layer in the high-temperature tunnel enhances with the increasing thickness of the layer, and its seismic isolation behaviour enhances with the increasing of the layer thickness and elastic modulus.

show abstract

Numerical study on airflow temperature field in a high-temperature tunnel with insulation layer

Cited by 77 publications

References 31 publications

A fully coupled seepage–heat transfer model including a dynamic heat transfer coefficient in fractured rock sample with a single fissure

A fully coupled seepage–heat transfer model including a dynamic heat transfer coefficient in fractured rock sample with a single fissure

Numerical Study on Damage Zones Induced by Excavation and Ventilation in a High-Temperature Tunnel at Depth

Application of thermal insulation layer in the tunnel with high temperature subjected to strong seismic motion

Contact Info

Product

Resources

About