Wyniki wyszukiwania - BazTech

1

Fusion model basedRUL prediction method of lithium-ion battery under working conditions

Fang Pengya, Sui Xiaoxiao, Zhang Anhao, Wang Di, Yin Liping

Eksploatacja i Niezawodność

|

2024

|

Vol. 26, no. 3

art. no. 186537

EN

Under working conditions, since the remaining useful life (RUL) prediction of lithium-ion battery is subject to uncertainties of random charging and discharging, and infeasibility of battery capacity test, a fusion model based RUL prediction method was proposed. First, the feature learning method of lithium-ion batteries was developed by synthesizing manual extraction and one-dimensional convolutional neural network (1DCNN) extraction. Then, a fused method was proposed to estimate the historical available capacity through exploring the spatial and temporal relationship of features, and the long short-term memory (LSTM) network model was adopted for predicting the RUL of lithium-ion battery. The proposed method was verified through the comparison of differentmethods, and the results show that it can realize highly precise and stable capacity estimation and RUL prediction under working conditions.

2

Analysis of progressive collapse of a super-long span latticed steel arch structure

Guo Shuangchao, Xu Delin, Shang Kaiguang, Yang Shuo, Wang Di, Li Gen, Zheng Bing, Jiao Yong

Journal of Theoretical and Applied Mechanics

|

2023

|

Vol. 61 nr 1

103--117

EN

The progressive collapse of a space grid structure which has a large number of members and a large span is the focus of current research. Before the progressive collapse of the structure, there is a problem of instability of the members. In this paper, dynamic nonlinear analysis of a super-long span latticed steel arch structure is carried out to study its progressive collapse process using a Kinematic Hardening Plasticity constitutive model compiled by Vumat material subprogram in Abaqus, which takes into account instability of the members. Differences in the dynamic response process of the structure at the collapse moment and the failure sequence of the members using the member stability model and the material failure constitutive model are compared. Compared with the material failure constitutive model, when the member stability constitutive model is used, the proportion of compressive buckling members in the structural failure is higher, and the bearing capacity of the structure is lower when the initial failure occurs. The structure suffers from localized member compressive failure rather than material yielding, which leads to the progressive collapse of the structure.

3

Fracture interference and propagation geometry of hydraulic fractures based on XFEM in an unconventional oil reservoir

Liang Shuang, Wang Di, Liu Dan, Tian Yang, Wang Haibo, Li Fengxia, Dong Gang, Yin Chengfeng, Yang Yi

Archives of Mining Sciences

|

2023

|

Vol. 68, no. 2

301--318

EN

Unconventional oil and gas reservoirs are characterised by low porosity, low permeability and low natural deliverability. At present, horizontal wells staged fracturing is an effective development method. However, in the case of staged hydraulic fracturing in horizontal wells, stress interference occurs between multiple fractures, leading to fracture deformation and even inhibiting the formation of fractures, thereby affecting reservoir production. In this paper, based on the extended finite element method (XFEM), considering the fluid flow in the fracture and fracturing fluid filtration, we analyse the effects of fracturing fluid pumping rate, fracture spacing and elastic modulus on horizontal in-situ stress, fracture parameters and fracture extension pattern during different fracturing initiation processes. The results show that the induced stress generated by the action of fracturing fluid changes the direction of horizontal in-situ stress in the elliptical region around the fracture. In the mode of simultaneous fracture initiation (TFIS), the extension of two symmetrical fractures is “repulsive”; in the mode of two fractures initiated at different times (TFIDT), the extension direction is “mutual attraction”. A large pumping rate and small elastic modulus are conducive to fracture propagation. In the TFIS mode, two fractures alternately expand, while in the TFIDT mode, the impact of rock mechanical properties and construction parameters on fracture propagation will be amplified. The extension of subsequent fractures will be restrained, especially when the fracture spacing is less than 10 m. The width of the previously created fracture will be severely affected, even causing a partial closure and becoming elongated fractures.

4

The cognition of the spatial art forms of tourist villages based on ecological engineering and sustainable development

Wang Di, Li Dazhuang

Ecological Chemistry and Engineering. S

|

2021

|

Vol. 28, nr 4

581--595

EN

With the development of information technology, the improvement of production processes and lifestyles, and the transformation of commercial economic models, the traditional agricultural industry cannot meet the increasing material and cultural needs of villagers. Therefore, the development of traditional tourist villages has transformed into being based on ecological engineering and sustainable development. The starting point of the existence of such tourist villages will be the protection and development of traditional villages. At the same time, the village space is the material carrier for the development of rural tourism, and the construction of a spatial form that is compatible with the tourism resource utilization model can effectively promote the development of rural tourism. Based on SWOT analysis, this article carefully analyses and summarises the domestic research on the sustainable development of tourist villages. The results show that such sustainable development effectively avoids the excessive development of resource elements during rural construction, which can lead to waste, and promotes the optimal use of resources. Since rural tourism has taken a sustainable development path, the average annual compound growth rate has reached as high as 31.2 %, which is considered very rapid growth. Tourist operating income has reached more than 30 %. It is expected that the national rural tourism income in 2021 will exceed 10,000 trillion yuan. Tourism villages will continue to consider ecological engineering and sustainable development as the starting point for promoting the development of rural tourism in China, popularising consumption, standardising services, diversifying benefits, and making products unique.