Prime Archives in Engineering最新文献

Compression Characteristics and Constitutive Model of Low-Exotherm Modified Polyurethane Grouting Materials 低放热改性聚氨酯注浆材料的压缩特性及本构模型

Prime Archives in Engineering Pub Date : 2020-11-09 DOI: 10.1155/2020/1958473

Shengjie Xu, S. Wang, Y. Zhong, Bei Zhang, Juan Zhang, Yanjun Wang, Liguo Zhao

{"title":"Compression Characteristics and Constitutive Model of Low-Exotherm Modified Polyurethane Grouting Materials","authors":"Shengjie Xu, S. Wang, Y. Zhong, Bei Zhang, Juan Zhang, Yanjun Wang, Liguo Zhao","doi":"10.1155/2020/1958473","DOIUrl":"https://doi.org/10.1155/2020/1958473","url":null,"abstract":"In permafrost regions, ordinary polyurethane grouting materials are not suitable for the repair and reinforcement of road engineering due to the release of a large amount of heat during the reaction process. In this study, the polyurethane grouting material is modified by changing the catalyst, blowing agent, and reaction scheme to reduce the heat released during the reaction. The stress-strain curves of low-exotherm polyurethane grouting material specimens possessing various densities are investigated by means of unconfined uniaxial compression experiments, and the stress-strain relationships and failure mode of low- and high-density specimens are analysed. The characteristics of three stages in the compression process of the materials, namely, the elasticity stage, platform stage, and densification stage, are studied. The compressive strength increases with the increase in density, and the brittle failure of materials with higher density is more obvious. From the microscopic point of view, combined with the experimental results, the constitutive model of low-exotherm modified polyurethane grouting material was established. The established model is in good agreement with the experimentally measured stress-strain curves and effectively predicted the stress-strain characteristics for a specimen possessing a different density.","PeriodicalId":380885,"journal":{"name":"Prime Archives in Engineering","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125402316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

A Ducted Photovoltaic Façade Unit with Buoyancy Cooling Part I Experiment 浮力冷却的导管式光伏发电机组第一部分试验

Prime Archives in Engineering Pub Date : 2019-04-16 DOI: 10.3390/BUILDINGS9040088

Abdel Rahman Elbakheit

{"title":"A Ducted Photovoltaic Façade Unit with Buoyancy Cooling Part I Experiment","authors":"Abdel Rahman Elbakheit","doi":"10.3390/BUILDINGS9040088","DOIUrl":"https://doi.org/10.3390/BUILDINGS9040088","url":null,"abstract":"A ducted photovoltaic façade (DPV) unit was studied using experimental prototype and simulated in a full scale computational fluid dynamics (CFD) model. The study comes in two parts; this is Part I, as detailed in the title above, and Part II is titled “A Ducted Photovoltaic Façade Unit with Buoyancy Cooling: Part II CFD Simulation”. The process adopted in the experimental study is replicated in the simulation part. The aim was to optimize the duct width behind the solar cells to allow for a maximum buoyancy-driven cooling for the cells during operation. Duct widths from 5 to 50 cm were tested in a prototype. A duct width of 45 cm had the maximum calculated heat removed from the duct; however, the lowest cell-operating temperature was reported for duct width of 50 cm. It was found that ΔT between ducts’ inlets and outlets range from 5.47 °C to 12.32 °C for duct widths of 5–50 cm, respectively. The ducted system enhanced module efficiency by 12.69% by reducing photovoltaic (PV) temperature by 27 °C from 100 °C to 73 °C. The maximum measured heat recovered from the ducted PV system was 422 W. This is 48.98% from the incident radiation in the test. The total sum of heat recovered and power enhanced by the ducted system was 61.67%.","PeriodicalId":380885,"journal":{"name":"Prime Archives in Engineering","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122508101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Stability Analysis of a Helicopter with an External Slung Load System 直升机外吊载系统稳定性分析

Prime Archives in Engineering Pub Date : 2016-06-01 DOI: 10.1155/2016/4195491

K. Thanapalan

引用次数: 4

Method for Evaluating the Effect of the Design and the Environmental Conditions of the Manufacturing Cells to Improve Work Performance 评价制造单元的设计和环境条件对提高工作性能的影响的方法

Prime Archives in Engineering Pub Date : 1900-01-01 DOI: 10.37247/paengg.1.2021.4

M. Montoya-Reyes, Á. González-Ángeles, M. Gil-Samaniego-Ramos, I. Mendoza-Muñoz, Juan Ling-López

引用次数: 0

A Ducted Photovoltaic Façade Unit with Buoyancy Cooling: Part II CFD Simulation 带浮力冷却的管道光伏发电机组:第二部分CFD模拟

Prime Archives in Engineering Pub Date : 1900-01-01 DOI: 10.37247/paengg.1.2021.9

Abdel Rahman

引用次数: 0