The Influence of Different Diving Angles on the Hydrodynamic Noise of Submarine EnclosuresLv, Bangjun; Chen, Yonghong
doi: 10.1088/1742-6596/2565/1/012006pmid: N/A
The hull is an important component of the submarine structure, and it is also one of the factors that affect the concealment of the submarine. By using the finite element method, a submarine model was established to analyze the hydrodynamic noise at the contact points between the front and rear of the hull and the hull under different diving angles. The results show that when the diving angle is about 10°, the hydrodynamic noise at the front and rear positions of the enclosure is relatively small. The research results provide a reference for ensuring the stealth operation conditions of submarines and have practical significance for improving the stealth of submarines.
Modeling and Analysis of Aluminum Cable Joints in Steady State for New Energy StationsGao, Zhao; Wang, Le; Zhang, Haoran; Li, Boyi; Fan, Lijun
doi: 10.1088/1742-6596/2565/1/012033pmid: N/A
Compared with copper cables, aluminum cables have certain advantages in engineering costs and transportation costs, but have installation difficulties in the application process. However, limited by the manufacturing process, installation technology, and operating conditions, the intermediate joint of the aluminum cable is prone to failures such as insulation deterioration caused by abnormal temperature. The temperature of the core of the conductor in a steady state in the cable joint is the most direct and effective physical quantity, which can reflect the operating state. So modeling and analysis of the aluminum cable joint, as well as the study of its internal temperature change mechanism and influencing factors, are to improve the process and installation level of the aluminum cable joint and to develop the basis of the corresponding temperature monitoring system. In this paper, the thermal conduction mechanism of aluminum cable joints in a steady state is analyzed by using the thermal circuit theory. Then, the thermal circuit model of aluminum cable joints in a steady state based on the equivalent thermal circuit model and its parameter calculation method are proposed. By building an experimental platform, the validation experiment finally proved the accuracy of the method proposed in this paper.
Numerical Study of Proppant Transport in Intersected Fractures for Supercritical Carbon Dioxide FracturingLiu, Boyu; Yao, Jun
doi: 10.1088/1742-6596/2565/1/012029pmid: N/A
This study employs Computational Fluid Dynamics (CFD) method to simulate particle transport in supercritical carbon dioxide fracturing. A dynamic leak-off model is integrated into the Eulerian-Eulerian two-fluid model. It systematically examines the transport of different-sized proppants in intersected fractures with leak-off and investigates the effects of proppant size, bypass fracture width, inter-fracture angle, and pumping schedule on the proppant distribution. Results show that the proppant split ratio increases with an increase in bypass fracture width and inter-fracture angle. Injecting larger-sized proppants before smaller-sized proppants can enhance the proppant bed length and height while reducing the proppant split ratio.
Renewable Energy Power System Unit Commitment Considering Regional Frequency Stability RequirementCao, Bin; Miao, Lifang; Liu, Hongqing; Lai, Shuyu; Wang, Cheng
doi: 10.1088/1742-6596/2565/1/012040pmid: N/A
With the development of new power systems, the formation of a “double high” pattern in frequency has made frequency security a prominent problem. It is particularly important to formulate a unit power generation plan with frequency security constraints at the day-ahead scale. However, a unit commitment model with frequency security constraints based on a unified frequency for the entire network cannot be used because the frequency exhibits spatial variations. This problem is solved in this study by establishing a single-machine aggregation model for the frequency response of a partitioned power system. In the unit commitment model, the frequency support between individual regions is established based on the distribution of the disturbance power over individual subregions. The index of the initial frequency change rate is introduced for each subregion to establish an analytical expression for the relationship between the frequency security constraints and the unit commitment scheme. Finally, the effectiveness of the model and the solution algorithm is verified for the improved IEEE39 node system.
Unsteady Simulation and Mode Analysis of Disturbed Cylinder FlowGong, Ziqiao
doi: 10.1088/1742-6596/2565/1/012015pmid: N/A
The unsteady simulation of cylinder flow with inlet velocity disturbance is simulated and compared with that without disturbance. POD is adopted to analyze and capture the dominant modes of the vortex street in the cylinder wake. The results show that the POD method is efficient in reconstructing the flow field. When the inlet velocity disturbance exists, the number of modes required to reconstruct the flow field accurately is almost unchanged, but the energy proportion of each mode changes. The larger the disturbance frequency is, the smaller the shape and vorticity magnitude of the vortex street is, and the slower the generation speed is. If the frequency deviates too much from the original frequency of the flow field, the effect of inlet velocity disturbance will be shielded.
Modelling Study of EMBr Effect on Interface Fluctuation and Melt Flow in a Thin Slab MouldLv, Xin-sheng; Xu, Lin; Liu, Cong; Guan, Duo-jiao; Pei, Qun-wu; Xu, He-yuan
doi: 10.1088/1742-6596/2565/1/012019pmid: N/A
Electromagnetic brakes (EMBrs) are regularly used in continuous casting to control interface fluctuations in a mould. In the research, to appraise the damping effect of EMBr technique, namely EMBr-ruler technique, the influence of magnetic field intensity on behaviours of melt flow and interface fluctuation in a Compact Strip Production (CSP) thin slab funnel mould are numerically simulated. The numerical results illustrate that the existence of the EMBr-ruler technique is conducive to inhibiting the impact of the ascending circulation on the interface in the CSP funnel mould. With the gradual enhancement of magnetic intensity, the service efficiency of the EMBr-ruler on the fluctuation of two-phase steel/slag interface is enhanced. For instance, by applying a magnetic induction intensity of 0.5 T, the maximum fluctuation height of two-phase steel/slag interface is decreased to 6.4 mm. This can well prevent surface defects, such as slag entrapment.
2D Structural Design and Numerical Simulation of a New Type of FairingXie, Wenbin; Le, Guigao
doi: 10.1088/1742-6596/2565/1/012026pmid: N/A
Based on the existing fairing, the 2D structure of the fairing is improved. Through the numerical simulation of the shape and height of the spoiler structure of the fairing, and the analysis and comparison of the obtained data, the fairing structure with good vortex-induced vibration suppression is designed. The results show that H = 6.5 mm’s semicircular spoiler structure with 45° tail-angle fairing on the middle line of the side has a good effect on suppressing vortex vibration.
Multi-type Adjustable Loads Aggregation Control Strategy for Industrial ParksLiu, Yu; Chen, Jinchang; Yang, Cheng; Miao, Lu; Tang, Yufeng; Yang, Ping
doi: 10.1088/1742-6596/2565/1/012041pmid: N/A
China’s industrial parks are the concentration areas of industrial enterprises. The aggregate regulation and control of various types of adjustable loads in industrial parks are effective means to achieve the consumption of renewable energy. However, there are many types of adjustable loads, along with varying amounts and response characteristics, which makes it difficult to achieve unified regulation. In view of the regulation and control characteristics of multiple types of adjustable loads in industrial parks, the regulation and control models of short-term interruptible load, reducible load, translatable load, transferable load and distributed energy storage are established respectively in this paper, aiming at minimizing the regulation cost and maximizing the benefits of the regulation and control auxiliary services, and the aggregate regulation and control strategy of multiple types of adjustable loads in industrial parks is proposed based on the electricity market environment to support the high proportion of renewable energy consumption of the new power system. At the same time, it will obtain auxiliary service income for industrial users. The simulation results of the example show that the proposed strategy reduces the power consumption cost of industrial users and effectively increases the usage of renewable energy without affecting the production of enterprises.
Application of Quality Inspection Data Association Rules in Measurement Terminal Based on MapReduceZhang, Bo; Liu, Yongping; Xia, Xin; He, Chuanliang; Zhen, Guolong; Xu, Pu
doi: 10.1088/1742-6596/2565/1/012037pmid: N/A
To solve the problem of not being able to intuitively lock the cause of defects when processing massive quality inspection datasets with multiple batches, types, and models of measurement terminals, a MapReduce-based Apriori algorithm is proposed. After the MapReduce algorithm model calculation, the processing efficiency of the quality inspection dataset has been significantly improved. Through the multi-node calculation and analysis of the single-phase electricity meter quality inspection dataset and the application of association rule mining, reasonable suggestions were given, which improved the professional value and quality supervision level of the quality inspection business.