Strojniški vestnik最新文献_第5页

Ultra-precision single-point diamond turning of a complex sinusoidal mesh surface using machining accuracy active control 利用加工精度主动控制对复杂正弦网格曲面进行超精密单点金刚石车削加工

Strojniški vestnik Pub Date : 1900-01-01 DOI: 10.5545/SV-JME.2021.7172

Pei Ning, Ji Zhao, Shijun Ji, Jingjin Li, D. Handa

引用次数: 0

Predictive estimation of sliding bearing load-carrying capacity and tribological durability 滑动轴承承载能力和摩擦学耐久性的预测估计

Strojniški vestnik Pub Date : 1900-01-01 DOI: 10.5545/SV-JME.2021.7139

M. Chernets, M. Opielak, A. Kornienko, O. Radko

引用次数: 1

A novel concept for boiling heat transfer enhancement 一种提高沸腾传热的新概念

Strojniški vestnik Pub Date : 1900-01-01 DOI: 10.1615/ICHMT.2004.INTTHERMSCISEMIN.820

D. W. Zhou

引用次数: 7

Single stage absorption system based on refrigerants R125 and R134A with DMETEG 基于R125和R134A制冷剂的单级吸收系统

Strojniški vestnik Pub Date : 1900-01-01 DOI: 10.1615/ICHMT.2000.THERSIEPROCVOL2THERSIEPROCVOL1.690

A. Levy, M. Jelínek, I. Borde

{"title":"Single stage absorption system based on refrigerants R125 and R134A with DMETEG","authors":"A. Levy, M. Jelínek, I. Borde","doi":"10.1615/ICHMT.2000.THERSIEPROCVOL2THERSIEPROCVOL1.690","DOIUrl":"https://doi.org/10.1615/ICHMT.2000.THERSIEPROCVOL2THERSIEPROCVOL1.690","url":null,"abstract":"Current developments in absorption technology include the research for new working pairs and new advance cycles that would facilitate increased efficiency of absorption units and extend applicability to different temperature ranges. Two refrigerants tetrafluoroethane (R134a) and pentafluoroethane (R125) that are alternatives to chlorofluorocarbons, in combination with absorbent dimethylether teraethylene glycol (DMETEG) were evaluated for possible utilization in absorption machines powered by low temperature heat sources. A computerized simulation program was used to compare the different refrigerant-absorbent pairs. The program was based on an advance single-stage cycle containing a jet ejector. The absorption cycle was represented in terms of heat and mass balance for each component and the calculations were based on the thermophysical properties of the refrigerant-absorbent pairs measured and evaluated in our laboratory. The aim of the cycle analysis was to evaluate the highest coefficient of performance (COP) and the lowest circulation ratio (f), which can be obtained for different generator temperatures under a constant evaporating and cooling water temperatures. The effects of changes in the evaporator and the cooling water temperatures on the COP and the circulation ratio, f, were also examined at the generator temperature at maximum COP.","PeriodicalId":237575,"journal":{"name":"Strojniški vestnik","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130172369","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: 7

Fire suppression using water mists: A numerical model 水雾灭火:数值模型

Strojniški vestnik Pub Date : 1900-01-01 DOI: 10.1615/ICHMT.2000.THERSIEPROCVOL2THERSIEPROCVOL1.300

G. Hadjisophocleous, M. An, V. Costa, A. Sousa

{"title":"Fire suppression using water mists: A numerical model","authors":"G. Hadjisophocleous, M. An, V. Costa, A. Sousa","doi":"10.1615/ICHMT.2000.THERSIEPROCVOL2THERSIEPROCVOL1.300","DOIUrl":"https://doi.org/10.1615/ICHMT.2000.THERSIEPROCVOL2THERSIEPROCVOL1.300","url":null,"abstract":"The modeling of fire suppression using fine watersprays is described within the context of an engineering computer model. A Lagrangian formulation was selected for the liquid droplet phase, while the gas phase uses an Eulerian formulation based on the RANS equations with a two-equation turbulence model. The fire is assumed to be a turbulent diffusion flame with its behavior dependent upon the supply of hydrocarbon fuel and the air accessing the fire. A feedback mechanism is also implemented, which dictates the rate of fuel evaporation. The flammability limits of the fuel vapor are taken into account, and the concentrations of fuel vapor, air, combustion products and steam evaporated from the droplets in the gas mixture are calculated by solving the equations for the mixture mass fractions. The droplets/gas phase interaction is described through source terms in the gas-phase equations. The time-dependent equations governing the gas phase are solved in primitive variable form by using a segregated technique. The ordinary differential equations for droplet motion, heating and evaporation are solved by an explicit forward time integration, which starts at the injection point. The droplet time step is determined by considering the turbulence dispersion of the droplets. The predictions produced by the model for the three different cases examined are physically realistic, notwithstanding the uncertainties associated with the experimental data and the input parameters.","PeriodicalId":237575,"journal":{"name":"Strojniški vestnik","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128764013","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: 2

Basic theory and design method of variable shaft angle line gear mechanism 变轴角直线齿轮机构的基本理论和设计方法

Strojniški vestnik Pub Date : 1900-01-01 DOI: 10.5545/SV-JME.2021.7216

Yangpeng Chen, H. Chao, Lyu Yueling

引用次数: 0

The use of a phase change material within a cylinder wall in order to detect knock in a gas SI engine 在汽缸壁上使用相变材料来检测燃气SI发动机的爆震

Strojniški vestnik Pub Date : 1900-01-01 DOI: 10.1615/ICHMT.2004.INTTHERMSCISEMIN.910

J. Bellettre, E. Ollivier, M. Tazerout

{"title":"The use of a phase change material within a cylinder wall in order to detect knock in a gas SI engine","authors":"J. Bellettre, E. Ollivier, M. Tazerout","doi":"10.1615/ICHMT.2004.INTTHERMSCISEMIN.910","DOIUrl":"https://doi.org/10.1615/ICHMT.2004.INTTHERMSCISEMIN.910","url":null,"abstract":"The present paper studies the possibility to develop a new method of knock detection in a gas SI engine. This method is based on the increase in'the wall heat flux when knock occurs. It also must be simple enough to be used by industry. In order to achieve this goal, a metallic Phase Change Material is put within the wall cylinder. The melting of the PCM means that knock has occurred and is persistent. The melting of such a phase change material would be easy to detect using industrial measurement tools. In this paper, numerical simulations of unsteady heat transfer across the cylinder wall are presented. Unsteady heat transfer from the hot gas to the wall chamber is simulated by a self-developed program. This program allows fixing instantaneous local heat flux values deduced from the literature in case of both normal and knocking combustion. Heat transfer across the cylinder wall is solved by the finite volume technique. Grid is validated by comparison with analytical results. Melting is treated by the Voller and Prakash model and Sodium is chosen as PCM. Among all the results, we can notice that an increase in the knock intensity changes the shape of the isothermal curves around and inside the PCM. This leads to an increase in the melting velocity with a higher rate than the increase in the heat flux.","PeriodicalId":237575,"journal":{"name":"Strojniški vestnik","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131406107","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: 2

Role of the heat-exchangers in the factor 4 energy policy 热交换器在因子4能源政策中的作用

Strojniški vestnik Pub Date : 1900-01-01 DOI: 10.1615/ICHMT.2000.THERSIEPROCVOL2.30

P. Novak

引用次数: 0

Heat transfer in laser pulse interaction with reactive substances 激光脉冲与反应物质相互作用中的热传递

Strojniški vestnik Pub Date : 1900-01-01 DOI: 10.1615/ICHMT.2000.THERSIEPROCVOL2THERSIEPROCVOL1.130

I. Assovskiy

{"title":"Heat transfer in laser pulse interaction with reactive substances","authors":"I. Assovskiy","doi":"10.1615/ICHMT.2000.THERSIEPROCVOL2THERSIEPROCVOL1.130","DOIUrl":"https://doi.org/10.1615/ICHMT.2000.THERSIEPROCVOL2THERSIEPROCVOL1.130","url":null,"abstract":"The purpose of this paper is to analyze thermal regime of a laser-pulse interaction with a substance reacting in bulk and on the surface. Emphasis is on the critical phenomena in non-resonant interaction of substance with laser beam, and how they depend on thermo-chemical and optical characteristics of system. It is shown that irradiation of exothermically reacting substance can induce its ignition, if the laser-beam diameter exceeds a critical one. This critical diameter depends on the pulse intensity and duration, as on the thermo-chemical characteristics of system. The cases of short-pulse and quasi-steady irradiation are considered in details. A role of soot particles or other absorbing micro-inclusions in the interaction is investigated. In certain field of the system parameters such micro-inclusions cause local heat explosion, due to exothermic reaction in environment. In the case of quasi-steady irradiation the explosion is induced if the particle diameter exceeds a critical one. This critical diameter depends on the initial temperature, reaction rate constants, as on radiation intensity. It is directly proportional to the characteristic space-scale of reaction in the system. The product of the particle critical diameter and the radiation intensity is approximately constant. In the case of short-pulse irradiation the highest temperature disturbance in the substance is caused by particles having certain medium diameter. This critical diameter increases with pulse duration and with heat-conductivity of the substance. The main results of consideration are illustrated by instances with reacting gas, condensed fuels, and explosives. The results application to typical problems of laser based diagnostics are also demonstrated.","PeriodicalId":237575,"journal":{"name":"Strojniški vestnik","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121729243","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: 1

Energy savings by recycling 回收利用节省能源

Strojniški vestnik Pub Date : 1900-01-01 DOI: 10.1615/ICHMT.2000.THERSIEPROCVOL2THERSIEPROCVOL1.780

M. Pavlovic

引用次数: 0