The temperature prediction of the Clamp-conductor coupling zone plays a crucial role in ensuring the safe and stable operation of overhead transmission lines and optimizing the thermal stability margin of transmission...The temperature prediction of the Clamp-conductor coupling zone plays a crucial role in ensuring the safe and stable operation of overhead transmission lines and optimizing the thermal stability margin of transmission lines.While existing research in this field has thoroughly explored temperature rise prediction,the focus has been relatively narrow,either targeting conductors exclusively or focusing solely on clamps,with little attention given to the temperature rise in the conductor-clampcoupling zoneor the influenceof clamp temperatureonconductor temperature rise.Based on this,considering axial heat transfer between the clamp and the conductor,this study develops a thermal model to calculate temperature in the clamp-conductor interface zone.A Whale Optimization Algorithm(WOA)-based parameter identification method is employed to overcome challenges in determining model parameters.To validate model performance,a current-carrying temperature-rise experimental platform was designed to supply data for both model verification and parameter identification.By comparing the calculation results with the experimental data,the results show that the maximum average error does not exceed 1.4%,and the maximum error is only 2.79%,verifying the validity of the parameter identificationmethod and thermalmodel.Thiswork lays a theoretical foundation for predicting temperature distributions at clamp-conductor interfaces under realistic meteorological conditions and supports short-termdynamic capacity increases for overhead conductors,demonstrating significant practical relevance.展开更多
The thermal deactivation of diesel soot particles exerts a significant influence on the control strategy for the regeneration of diesel particulate filters(DPFs).This work focused on the changes in the surface functio...The thermal deactivation of diesel soot particles exerts a significant influence on the control strategy for the regeneration of diesel particulate filters(DPFs).This work focused on the changes in the surface functional groups,carbon chemical state,and graphitization degree during thermal treatment in an inert gas environment at intermediate temperatures of 600℃,800℃,and 1000℃ and explore the chemical species that were desorbed from the diesel soot surface during thermal treatment using a thermogravimetric analyser coupled with a gas-chromatograph mass spectrometer(TGA-GC/MS).The surface functional groups and carbon chemical statewere characterized using Fourier transform infrared spectroscopy(FT-IR)and X-ray photoelectron spectroscopy(XPS).The graphitization degree was evaluated by means of Raman spectroscopy(RS).The concentrations of aliphatic C–H,C–OH,C=O,and O–C=O groups are reduced for diesel soot and carbon black when increasing the thermal treatment temperature,while the sp^(2)/sp^(3) hybridized ratio and graphitization degree enhance.These results provide comprehensive evidence of the decreased reactivity of soot samples.Among oxygenated functional groups,the percentage reduction during thermal treatment is the largest for the O–C=O groups owing to its worst thermodynamic stability.TGA-GC/MS results show that the aliphatic and aromatic chains and oxygenated species would be desorbed from the soot surface during 1000℃ thermal treatment of diesel soot.展开更多
基金supported by the Technology Innovation Leading Program of Shaanxi(2024QCY-KXJ-009)the Research Plan of the EducationDepartment of Shaanxi Province(23JC028)+1 种基金supported by the National Key Laboratory of Metal Forming Technology and Heavy Equipment B2408100.W14.Key Research and Development Program of Shaanxi(2025CY-YBXM-489).
文摘The temperature prediction of the Clamp-conductor coupling zone plays a crucial role in ensuring the safe and stable operation of overhead transmission lines and optimizing the thermal stability margin of transmission lines.While existing research in this field has thoroughly explored temperature rise prediction,the focus has been relatively narrow,either targeting conductors exclusively or focusing solely on clamps,with little attention given to the temperature rise in the conductor-clampcoupling zoneor the influenceof clamp temperatureonconductor temperature rise.Based on this,considering axial heat transfer between the clamp and the conductor,this study develops a thermal model to calculate temperature in the clamp-conductor interface zone.A Whale Optimization Algorithm(WOA)-based parameter identification method is employed to overcome challenges in determining model parameters.To validate model performance,a current-carrying temperature-rise experimental platform was designed to supply data for both model verification and parameter identification.By comparing the calculation results with the experimental data,the results show that the maximum average error does not exceed 1.4%,and the maximum error is only 2.79%,verifying the validity of the parameter identificationmethod and thermalmodel.Thiswork lays a theoretical foundation for predicting temperature distributions at clamp-conductor interfaces under realistic meteorological conditions and supports short-termdynamic capacity increases for overhead conductors,demonstrating significant practical relevance.
基金supported by the National Natural Science Foundation of China (No.52006054)the State Key Laboratory of Engines at Tianjin University (No.K2021-05)+1 种基金the European Union’s projects MODALES (No.815189)nPETS (No.954377)
文摘The thermal deactivation of diesel soot particles exerts a significant influence on the control strategy for the regeneration of diesel particulate filters(DPFs).This work focused on the changes in the surface functional groups,carbon chemical state,and graphitization degree during thermal treatment in an inert gas environment at intermediate temperatures of 600℃,800℃,and 1000℃ and explore the chemical species that were desorbed from the diesel soot surface during thermal treatment using a thermogravimetric analyser coupled with a gas-chromatograph mass spectrometer(TGA-GC/MS).The surface functional groups and carbon chemical statewere characterized using Fourier transform infrared spectroscopy(FT-IR)and X-ray photoelectron spectroscopy(XPS).The graphitization degree was evaluated by means of Raman spectroscopy(RS).The concentrations of aliphatic C–H,C–OH,C=O,and O–C=O groups are reduced for diesel soot and carbon black when increasing the thermal treatment temperature,while the sp^(2)/sp^(3) hybridized ratio and graphitization degree enhance.These results provide comprehensive evidence of the decreased reactivity of soot samples.Among oxygenated functional groups,the percentage reduction during thermal treatment is the largest for the O–C=O groups owing to its worst thermodynamic stability.TGA-GC/MS results show that the aliphatic and aromatic chains and oxygenated species would be desorbed from the soot surface during 1000℃ thermal treatment of diesel soot.
