检索结果-内蒙古大学图书馆

Effect of the Original Clustering Degree of Reclaimed Asphalt Pavement and design parameters on Properties of Recycled Asphalt Mixtures

引用

JOURNAL OF MATERIALS IN CIVIL ENGINEERING 2025年第2期37卷

作者： Zhang, Yining Chu, Xiaolong Zhu, Wenkai Zhan, Xiaoli Dong, Haidong Liu, Dong Wang, Bingjian Cheng, Huailei Sun, Lijun Zhejiang Univ Technol Fac Civil Engn Hangzhou 310023 Peoples R China Zhejiang Univ Technol Fac Civil Engn Zhejiang Key Lab Civil Engn Struct & Disaster Prev Hangzhou 310023 Peoples R China Zhejiang Shunchang Highway Maintenance Co Ltd Zhejiang Prov Engn Res Ctr High Way Intelligent Ma Hangzhou 310051 Peoples R China Zhejiang Dev & Planning Inst Res Dept Macroecon Hangzhou 310012 Peoples R China Tongji Univ Key Lab Rd & Traff Engn Minist Educ Shanghai 201804 Peoples R China

The use of reclaimed asphalt pavement (RAP) has brought enormous potential economic and environmental benefits to society. However, the cluster phenomenon of RAP particles in recycled hot-mix asphalt (HMA) has limited the extensive usage of RAP to a certain extent. Therefore, this research evaluated the effect of the original clustering degree of RAP and design parameters on the properties of recycled HMAs and the qualitative status of RAP cluster in recycled mixes. Six groups of mixes were designed, including one control group in which the RAP particles were designed as completely no cluster status, three experimental groups in which the RAP particles were designed at different original clustering degrees, and another two groups designed under different preheating temperatures and blending time. Then, the volumetric indicators, water stability, rutting, thermal cracking, and abrasion performance of each group were evaluated. It can be found that the RAP cluster was partially dispersed during the mixing and varied with different design parameters. The incomplete dispersion of fine RAP cluster acted as a "fake coarse aggregate" and affected the volumetric results and performance of final mixtures. Therefore, it may be inaccurate to design the aggregate gradation of recycled HMAs solely based on the extracted curve or the black curve of original RAP particles. The dispersion process of the RAP cluster during the mixing should not be ignored. In addition, the results also indicated that the original clustering degree of RAP particles may need to be carefully controlled during the construction.

关键词： Recycled hot-mix asphalt Cluster performance Original clustering degree design parameters Performance Reclaimed asphalt pavement (RAP)

来源：评论

学校读者我要写书评

暂无评论

Effect of design parameters on low-temperature cracking resistance of recycled hot-mix asphalt mixtures

引用

MATERIALS AND STRUCTURES 2025年第1期58卷 1-20页

作者： Yao, Yuquan Yang, Jiangang Gao, Jie Xu, Jing Zhang, Yang Yu, Shukai East China Jiaotong Univ Sch Civil Engn & Architecture Nanchang 330013 Jiangxi Peoples R China

This study aims to investigate the effects of different design parameters on the low-temperature crack resistance of recycled asphalt mixtures and to provide design guidance for recycled asphalt mixtures. Three material composition factors (reclaimed asphalt pavement (RAP) content, gradation type, and asphalt content) and four mixing process factors (RAP preheating temperature, mixing duration, mixing temperature, and mixing sequence) were considered. Using a single-factor controlled variable method, AC-20 recycled asphalt mixture was designed to study low-temperature crack resistance through a semi-circular bending (SCB) test, the significance of the effects of different factors was analyzed using the orthogonal test, and the fracture surface morphology was observed. Results show that both material composition and mixing processes impact the low-temperature crack resistance of recycled asphalt mixtures. Specifically, lower RAP content, higher asphalt content, higher mixing temperature, longer mixing duration, and mixing sequence I favor improved low-temperature crack resistance. Gradation type and RAP preheating temperature showed non-linear effects, peaking before declining. Material composition, especially asphalt content, has a more significant effect on the low-temperature crack resistance than mixing process factors. To achieve optimal low-temperature crack resistance, it is recommended to optimize the material composition of recycled asphalt mixture and control the RAP preheating temperature to 110 degrees C, maintain laboratory mixing duration of at least 150s, set the mixing temperature to at least 160 degrees C, and follow mixing sequence I.

关键词： Reclaimed asphalt pavement (RAP) Recycled asphalt mixture design parameters Low-temperature crack resistance Semi-circular bending (SCB)

来源：评论

学校读者我要写书评

暂无评论

Investigating the impacts of heat sink design parameters on heat dissipation performance of semiconductor packages

引用

INTERNATIONAL JOURNAL OF THERMAL SCIENCES 2025年 208卷

作者： Apalowo, Rilwan Kayode Abas, Aizat Salim, Muhammad Razin Sharif, Mohamed Fikri Mohd Kok, Chia Siang Univ Sains Malaysia Sch Mech Engn Engn Campus Nibong Tebal 14300 Malaysia Fed Univ Technol Akure Dept Mech Engn PMB 704 Akure Nigeria Western Digital Corp MK13Plot 301A Persiaran Cassia Selatan 1 Taman Pe Batu Kawan 14100 Penang Malaysia

This study investigates the impacts of various heat sink design parameters on the thermal dissipation performance of semiconductor packages using a heat sink as the thermal solution. A multiphase finite volume model was developed for heat transfer simulations to determine the heat sink and junction temperatures of the semiconductor assembly. Additionally, a heat transfer experiment was conducted to measure these temperatures over time. The numerical predictions closely matched the experimental results, with a maximum disparity of 0.26 % for junction temperature and 0.42 % for heat sink temperature, confirming the reliability of the numerical model. The results revealed that pin fin heat sinks demonstrated marginally superior thermal performance, reducing the junction temperature by 0.05 % compared to parallel heat sinks. Increasing the base area from 20x20 mm2 to 50x50 mm2 resulted in a significant 31.64 % reduction injunction temperature and a corresponding reduction in heat sink temperature from 60.41 degrees C to 36.42 degrees C. Extending fin height from 10 mm to 50 mm led to an 18.73 % decrease injunction temperature and a reduction in heat sink temperature from 46.07 degrees C to 34.56 degrees C. Enhancing the base thickness from 2 mm to 15 mm achieved a 24.35 % reduction injunction temperature and a decrease in heat sink temperature from 63.2 degrees C to 44.05 degrees C. The study concludes that optimizing these design parameters can substantially enhance heat dissipation, improving the reliability and efficiency of semiconductor devices.

关键词： Semiconductor package Heat transfer Finite volume method Junction temperature Heat sink temperature design parameters

来源：评论

学校读者我要写书评

暂无评论

Performance and optimal design parameters of tunnel lining CHEs under typical design conditions

引用

RENEWABLE ENERGY 2025年 238卷

作者： Ji, Yongming Ji, Chengfan Shen, Shouheng Zhang, Jun Hu, Songtao Qingdao Univ Technol Sch Environm & Municipal Engn Qingdao 266033 Shandong Peoples R China Jinma Energy Saving Technol Co LTD Shenzhen 115002 Guangdong Peoples R China Qingdao Metro Grp Co Ltd Qingdao 266035 Shandong Peoples R China

The subway source heat pump system (SSHPS) incorporating a tunnel lining capillary heat exchanger (CHE) is an efficient technology for mitigating thermal degradation in subway tunnels while fully harnessing geothermal energy for heating and cooling purposes. Although extensive research has been conducted on the performance of tunnel lining heat exchangers, a practical engineering design method is still lacking. The objective of this study is to analyze the heat transfer characteristics of tunnel lining CHEs under typical design conditions and subsequently determine the optimal design conditions based on the analysis results. A numerical model of tunnel lining CHEs was developed using ANSYS, based on a demonstration project of SSHPS in Qingdao. Subsequently, the heat transfer performance of CHEs under various design parameters was simulated and analyzed. Finally, a statistical analysis was conducted to examine the impact of different factors on the heat transfer performance of CHEs. The analysis results indicate that the tunnel air temperature has the most significant influence, followed by the CHE inlet temperature parameter and the length of CHE laying pipe. The impact of the CHE inlet flow velocity is minimal. It is recommended that, during the design stage of a CHE heat exchanger, priority should be given to controlling the tunnel air temperature, optimizing the CHE inlet temperature and pipe length, and setting a minimum possible CHE inlet flow velocity. The optimal combination of design parameters for the tunnel lining CHEs were determined as follows: under the cooling mode, a tunnel air temperature of 23 degrees C, a CHE design inlet temperature of 39 degrees C, a laying pipe length of 6 m, and an inlet flow velocity of 0.08 m/s;under the heating mode, a tunnel air temperature of 20 degrees C, a design inlet temperature of 4 degrees C, a laying pipe length of 6 m, and an identical flow velocity of 0.08 m/s. This study can serve as a valuable reference for tunn

关键词： Geothermal energy Energy tunnel Heat exchanger design parameters Performance

来源：评论

学校读者我要写书评

暂无评论

Experimental study on fire temperature field of extra-long highway tunnel under the effect of auxiliary channel design parameters

引用

CASE STUDIES IN THERMAL ENGINEERING 2025年 67卷

作者： Tan, Yinjun Li, Jie Li, Huayun Li, Zhisheng Xihua Univ Sch Architecture & Civil Engn Chengdu 610039 Peoples R China Xihua Univ Sch Emergency Management Chengdu 610039 Peoples R China Hebei Univ Engn Sch Min & Geomat Engn Handan 056038 Peoples R China

Accounting for the auxiliary channel's design parameters, 96 model tests on tunnel fires were conducted. The primary investigation centred on the influence of inclined shaft angle, the diameter and height of the vertical shaft on the temperature fields within extra-long highway tunnels during fires. It was observed that the HRR of a square-shaped fire source correlates linearly with the burner's surface area. The design parameters of the inclined and vertical shafts predominantly affect the temperature distribution in the vicinity of the tunnel's intersection. As the inclined shaft's angle is increased from 3 degrees to 12 degrees, and the vertical shaft's diameter and height are increased from 0.4 m to 0.7 m and from 4 m to 10 m, respectively, the maximum temperature variation percentages are 23.7 %, 27.3 %, and 25 %, respectively. When the angle and length of the inclined shaft are kept within 12 degrees and 100m, changes in the shaft's angle have little impact on the temperature of the vault in front of the intersection. An increase in the vertical shaft's height from 4m to 10m results in a 14 % maximum temperature difference in the intersection's front area.

关键词： Extra-long highway tunnel fire Longitudinal ventilation Auxiliary channel design parameters Vault temperature Model test

来源：评论

学校读者我要写书评

暂无评论

Relationship between design parameters of kitchen drainage system for restaurant and deposits: based on simulation and experiment

引用

URBAN WATER JOURNAL 2025年第3期22卷 313-322页

作者： Yan, Xin Chen, Yilin Chen, Yuhao Guan, Yuxi Fang, Zheng Jin, Tianci North China Univ Water Resources & Elect Power Sch Environm & Municipal Engn Zhengzhou Henan Peoples R China Shenzhen Water & Environm Grp Co LTD Technol Dept Shenzhen Guangdong Peoples R China Wuhan Univ Sch Civil Engn Wuhan Hubei Peoples R China Natl Energy Adm Large Dam Safety Supervis Ctr Hangzhou Zhejiang Peoples R China

This paper conducts a small-scale hydraulic experiment and uses numerical simulation to jointly investigate the relationship between kitchen pipe design parameters and Fat, oil and grease (FOG) deposits when using food waste disposers (FWDs). In the experiment, the amount of pipe deposition is measured to evaluate the impact of different slopes and U-bend and 90 degrees bend. The deposition rates and positions are assessed for four slopes and elbows in the simulation. At a flow rate of 1.0 L/s and a slope of 1.20%, the adhesion amount of FOG deposits is maximum. U-bend has the greatest effect on the adhesion of the deposits while 90 degrees bend is minimal. The deposition rate will rise with higher slope and flow rate. New design parameters are proposed, including that the most effective slope is 0.40% within the range of 0.40%-4.80%, the appropriate use of 90 degrees bend and P-bend, and the optimum cleaning time.

关键词： Water and sanitation FOG deposits kitchen drainage system FWDs design parameters

来源：评论

学校读者我要写书评

暂无评论

Research on the transient tribo-dynamic performance of water-lubricated bearing rotor system considering different design parameters

引用

PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART C-JOURNAL OF MECHANICAL ENGINEERING SCIENCE 2025年

作者： Chen, Ziqi Wang, Ji Li, Rui Liu, Yujun Dalian Univ Technol Sch Naval Architecture & Ocean Engn Dalian Peoples R China Dalian Univ Technol State Key Lab Struct Anal Ind Equipment Dalian Peoples R China Dalian Key Lab Adv Shipbuilding Technol Dalian Peoples R China

The leading cause of the rotor's unstable vibration is the significant nonlinear hydrodynamic impact of the water-lubricated bearing (WLB). To investigate the correlation between design variables and the transient tribo-dynamic characteristics of a water-lubricated bearing rotor system (WLBRS), in this study, multi-scale multiphysics modelling and analysis of coupled interfacial lubrication, asperity contact and elastic deformation are carried out to develop a transient mixed elastohydrodynamic lubrication (MEHL) model for WLBRS. A comparison of experimental and numerical data from published literature verifies the validity of the model. On this basis, an investigation is conducted on the impact of design factors, such as length-to-diameter ratio, clearance ratio, bearing bush elastic modulus, surface roughness, and unbalanced eccentricity, on several aspects of the WLBRS. These aspects include the rotor orbit, minimum water film thickness, frictional coefficient, contact force, hydrodynamic force, and transient dynamic response. The results indicate that there are effective methods for suppressing rotor vibration, improving load capacity, and enhancing the operational stability of WLB. This study provides valuable recommendations for the optimum design and vibration control of WLB.

关键词： Water-lubricated bearing design parameters transient tribo-dynamic vibration control multiscale multiphysics modelling and analysis

来源：评论

学校读者我要写书评

暂无评论

Sensitivity analysis of design parameters on the seismic performance of self-centering precast segmental bridge columns

引用

SOIL DYNAMICS AND EARTHQUAKE ENGINEERING 2025年 190卷

作者： Gao, Ruofan Luo, Yingjie He, Jingran Jinan Univ Sch Mech & Construct Engn 601 West Huangpu Ave Guangzhou 510632 Peoples R China Guangdong Univ Technol Sch Civil & Transportat Engn Univ Mega Ctr Guangzhou 510006 Guangdong Peoples R China

Prior studies on the parameter sensitivity analysis of the seismic performance of self-centering precast segmental bridge columns (SC-PSBCs), concentrated on parameters like axial compression ratio and shear span ratio, have overlooked other critical factors. This oversight indicates an urgent need for a more systematic and comprehensive sensitivity analysis to uncover the key factors influencing the seismic behavior of SC-PSBCs. The present study conducts a finite element-based sensitivity analysis to scrutinize the influences of various design parameters on the seismic performances of SC-PSBCs. To begin with, a refined finite element model of the SC-PSBC is established and validated using data from cyclic load tests. Utilizing the validated model as a foundation, a systematic exploration is performed on parameters including the strength of energy-dissipating (ED) reinforcement, unbonded length of ED reinforcement, concrete strength, and layout of post-tensioned (PT) tendons, along with nine additional parameters, aiming to uncover their distinct influences on the hysteretic behavior, lateral load-bearing capacity, energy dissipation, and residual displacement of SC-PSBCs. It is found that the energy dissipation exhibits the least sensitivity to parameter changes. Nonetheless, it is markedly influenced by the reinforcement ratio of ED bars, which shows a clear and significant positive correlation. Conversely, the residual displacement is responsive to a multitude of parameters. Notably, the shear span ratio emerges as the most important determinant. An increase in this ratio is associated with a marked decrease in the residual displacement ratio. Furthermore, the results indicate that the unbonded region of ED bars positioned within the foundation reduces the residual displacement without substantially compromising the lateral bearing capacity and energy dissipation capacity. In addition, the PT tendons could be strategically placed at the corners of four sides to

关键词： Self-centering precast segmental bridge columns Seismic performance design parameters Sensitivity analysis Finite element analysis

来源：评论

学校读者我要写书评

暂无评论

Numerical Analysis of Bio-Emulated Flow Channel: Effect of design and Operating parameters on PEM Fuel Cell Performance

引用

IRANIAN JOURNAL OF SCIENCE AND TECHNOLOGY-TRANSACTIONS OF MECHANICAL ENGINEERING 2025年第3期49卷 1231-1248页

作者： Bondada, Yeswanth Yadav Golagani, Naga Srinivasulu Natl Inst Technol Warangal Dept Mech Engn Warangal Telangana India

Hydrogen energy and proton exchange membrane fuel cells (PEMFCs) have become widely embraced technologies in response to global concerns about environmental issues and the pursuit of other forms of energy. This study investigates PEMFC performance by introducing a new bio-emulated flow channel (BEFC) design inspired by an external carotid artery with branches. It also describes how BEFC affects the cell performance, taking into account the design geometries such as the width and depth of the flow channel, along with cell operating parameters like temperature, relative humidity (RH), and pressure. Simulation results indicated that a BEFC design, which includes a central channel with branching structures similar to the carotid artery, improves reactant distribution and water management. The performance data reveal that PEMFC with a 1 mm flow channel width and 1 mm flow channel depth achieves a maximum power density of 0.5758 W/cm2. Furthermore, increasing the operating temperature of the cell from 40 to 70 degrees C enhances performance due to better reaction kinetics. However, temperatures above 70 degrees C result in decreased performance due to increased water evaporation. The study also reveals that increasing relative humidity (RH) to 100% and raising operating pressures from 1 to 4 bar significantly improves power output by lowering Ohmic losses and raising reactant partial pressures. Overall, this study shows that optimal channel design and fuel cell operating conditions can greatly enhance PEMFC performance.

关键词： Computational fluid dynamics (CFD) Proton exchange membrane (PEM) External carotid artery Operation parameters design parameters

来源：评论

学校读者我要写书评

暂无评论

design parameters influencing non-uniform current distributions in superconducting multi-stage stranded cables

引用

PHYSICA C 1998年第1-4期310卷 358-366页

作者： Seo, K Hasegawa, M Morita, M Yoshimura, H Mitsubishi Elect Co Adv Technol R&D Ctr Electromech Syst Dept Amagasaki Hyogo 661 Japan

We have suggested that non-uniform currents occur due to certain design parameters, for example a combination of cabling pitches, in a previous study. In the present study, we evaluate the occurrences of non-uniform current distributions in terms of design parameters, i.e., the combination of cabling pitches, winding methods (solenoidal and pancake winding) and cross-sectional shape of the cable by numerical analyses. Finally, some basic design concepts to solve this problem are proposed. (C) 1998 Elsevier Science B.V. All rights reserved.

关键词： current distribution superconducting cable design parameters

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：