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Analysis of the Effects of Catalytic Converter on Automotive Engines Performance Through Real-Time Simulation Models 利用实时仿真模型分析催化转化器对汽车发动机性能的影响
IF 2.3 Q2 ENGINEERING, MECHANICAL Pub Date : 2019-08-01 DOI: 10.3389/fmech.2019.00048
A. Gambarotta, V. Papetti, P. Dimopoulos Eggenschwiler
Today restrictions on pollutant emissions require the use of catalyst-based after-treatment systems as a standard both in SI and in Diesel engines. The application of monolith cores with a honeycomb structure is an established practice: however, to overcome drawbacks such as weak mass transfer from the bulk flow to the catalytic walls as well as poor flow homogenization, the use of ceramic foams has been recently investigated as an alternative showing better conversion efficiencies (even accepting higher flow through losses). The scope of this paper is to analyse the effects of foam substrates characteristics on engine performance. To this purpose a 0D “crank-angle” real-time mathematical model of an I.C.Engine developed by the Authors has been enhanced improving the heat exchange model of the exhaust manifold to take account of thermal transients and adding an original 0D model of the catalytic converter to describe mass flows and thermal processes. The model has been used to simulate a 1.6l turbocharged Diesel engine during a driving cycle (EUDC). Effects of honeycomb and foam substrates on fuel consumption and on variations of catalyst temperatures and pressures are compared in the paper.
今天,对污染物排放的限制要求使用基于催化剂的后处理系统作为SI和柴油发动机的标准。蜂窝结构的整体芯的应用是一种已建立的实践:然而,为了克服诸如从体流到催化壁的弱传质以及流动均质性差等缺点,陶瓷泡沫的使用最近被研究为一种替代方案,显示出更好的转化效率(甚至接受更高的流过损失)。本文的研究范围是分析泡沫衬底特性对发动机性能的影响。为此,对作者开发的内燃机零维“曲柄角”实时数学模型进行了改进,改进了排气歧管的热交换模型以考虑热瞬态,并增加了催化转化器的原始零维模型以描述质量流和热过程。该模型已被用来模拟一个1.6升涡轮增压柴油发动机在一个驾驶循环(EUDC)。本文比较了蜂窝基材和泡沫基材对燃料消耗以及催化剂温度和压力变化的影响。
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引用次数: 4
Real World Fuel Consumption and Emissions From LDVs and HDVs 现实世界中ldv和hdv的燃料消耗和排放
IF 2.3 Q2 ENGINEERING, MECHANICAL Pub Date : 2019-07-31 DOI: 10.3389/fmech.2019.00045
Konstantin Weller, S. Lipp, Martin Röck, C. Matzer, Andreas Bittermann, S. Hausberger
Real world emission and energy consumption behavior from vehicles is a key element for meeting air quality and greenhouse gas (GHG) targets for any country. While CO2 fleet targets for vehicles are defined on basis of standardized test procedures, in real driving conditions manifold parameters show large variabilities. Main differences are Driving cycle Vehicle loading and driving resistances Ambient temperature levels, start conditions and trip length Gear shift behavior of the drivers Power demand from auxiliaries Fuel quality For the upcoming update of the Handbook Emission Factors for Road Transport (HBEFA 4.1) we have performed analysis, measurements and simulations to elaborate real world energy consumption values for 2-wheelers, passenger cars (PC), light commercial vehicles (LCVs) and heavy duty vehicles (HDVs), so called emission factors (EF). EFs show fuel consumption or emission level in [g/km] and [#/km] for fuel, gaseous exhaust gas components and also for the particle number (PN). EFs are provided for a lot of different traffic situations covering stop & go up to highway for different road gradient categories. EFs are different for each vehicle category and for each powertrain technology and emission standard (from EURO 0 gasoline PC to EURO VI HDV with CNG engine). To produce the EFs, vehicle tests from chassis dyno and from on-board measurements were collected in all European labs to set up models for all vehicle segments in the passenger cars and heavy duty emission model (PHEM). The models for PC and LCVs were based on weight and road load data available from the type approval test, the worldwide harmonized light vehicles test procedure (WLTP), and then calibrated in a stepwise approach to consider all influences in real world driving. Finally, the results for new vehicle fleet fuel consumption values were compared with data from the fuel consumption monitoring data base. For HDVs, the models are based on data from the development of the HDV CO2 determination method (Regulation (EU) 2017/2400, “VECTO”). The methods and also the results in terms of differences between real world and type approval for loading, road load, energy consumption and emission levels are described in this paper.
在现实世界中,车辆的排放和能源消耗行为是任何国家实现空气质量和温室气体(GHG)目标的关键因素。虽然车辆的二氧化碳排放目标是根据标准化测试程序确定的,但在实际驾驶条件下,多种参数显示出很大的变化。主要区别在于驾驶周期车辆负载和驾驶阻力环境温度水平,启动条件和行程长度驾驶员换挡行为辅助设备的动力需求燃料质量对于即将更新的《道路运输排放因素手册》(HBEFA 4.1),我们进行了分析,测量和模拟,以详细阐述两轮车,乘用车(PC),轻型商用车(lcv)和重型车辆(hdv),即所谓的排放因子(EF)。EFs显示燃料消耗或排放水平,单位为[g/km]和[#/km],包括燃料、气体废气成分和颗粒数(PN)。EFs提供了许多不同的交通情况,包括不同道路坡度类别的停车和上行高速公路。不同的车辆类别、动力总成技术和排放标准(从欧0汽油PC到欧6 HDV CNG发动机)都有不同的EFs。为了生产EFs,在所有欧洲实验室收集了底盘动态和车载测量的车辆测试,以建立乘用车和重型排放模型(PHEM)中所有车辆部分的模型。PC和lcv的模型基于型式认可试验和全球统一轻型车辆试验程序(WLTP)提供的重量和道路载荷数据,然后以逐步校准的方法考虑实际驾驶中的所有影响。最后,将新车组油耗值计算结果与油耗监测数据库数据进行比较。对于HDV,模型基于HDV CO2测定方法(法规(EU) 2017/2400,“VECTO”)开发的数据。本文描述了这些方法以及实际情况与型式认可的装载、道路装载、能耗和排放水平之间的差异。
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引用次数: 13
Sliding Walk With Friction Control of Double-Network Gel on Feet of Inchworm Robot 基于双网凝胶摩擦控制的尺蠖机器人足部滑动行走
IF 2.3 Q2 ENGINEERING, MECHANICAL Pub Date : 2019-07-19 DOI: 10.3389/fmech.2019.00044
Minoru Takagi, Kazunari Yoshida, H. Hoshino, R. Tadakuma, Yoshiyuki Suzuri, H. Furukawa
Soft-matter robotics, which is named for robots made from soft materials, will possibly conquer the limit of conventional rigid body dynamics of hard robots made from hard materials. For example, a snake-like robot, of which body is made from soft materials, will walk in various environments including narrow space like drain pipes with complicated structure. Here we developed a walking robot with the friction control of double-network hydrogel (DN gel) on its feet, as the first model based on the concept of the soft-matter robotics. It is found that with appropriate control of the friction of DN gel, the inchworm walking robot has realized its high enough velocity for pipe inspection. We discussed the physical principle of the walking motion of the inchworm search robot and its actual mechanism to provide thrust for its walking motion.
软物质机器人(soft -matter robotics)是以软材料制造的机器人命名的,它将有可能突破传统硬材料制造的硬质机器人的刚体动力学极限。例如,蛇形机器人,其身体由柔软材料制成,可以在各种环境中行走,包括结构复杂的排水管等狭窄空间。本文基于软物质机器人的概念,开发了一种基于双网状水凝胶(DN gel)摩擦控制的步行机器人。研究发现,通过适当控制DN凝胶的摩擦力,尺蠖行走机器人可以实现足够高的管道检测速度。讨论了尺蠖搜索机器人行走运动的物理原理以及为行走运动提供推力的实际机构。
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引用次数: 10
The Combined Thermal and Mechanical Effect of an Interstitial Gas on Thermal Rectification Between Periodically Grooved Surfaces 间隙气体对周期性沟槽表面间热整流的热学和力学综合效应
IF 2.3 Q2 ENGINEERING, MECHANICAL Pub Date : 2019-07-16 DOI: 10.3389/fmech.2019.00042
K. Chumak, R. Martynyak
This paper presents a study on the combined thermal and mechanical effect of interstitial gas on thermal rectification between a periodically grooved surface and a flat one. To evaluate the interstitial medium influence, the analytico-numerical solution to the corresponding thermoelastic contact problem is constructed taking into account the effect of thermal strains on gap deformation. The results are provided for the Stainless Steel AISI 304 – Aluminum Alloy A380 pair in the presence of air or krypton in the interface gaps. The effects of the gas thermal conductivity and pressure, the imposed pressure and heat flux, and the maximum groove height on the effective thermal contact resistance and the level of thermal rectification are analyzed. It is revealed that taking into account the mechanical effect of the gap filler leads to lower values of thermal rectification level. Also, the change of the gap filler thermal conductivity has more pronounced effect that the change of its pressure.
本文研究了间隙气体对周期性沟槽表面与平面表面之间热整流的热学和力学综合效应。为了评估间隙介质的影响,考虑热应变对间隙变形的影响,构造了相应的热弹性接触问题的解析数值解。结果提供了在界面间隙存在空气或氪的情况下,不锈钢AISI 304 -铝合金A380对。分析了气体导热系数和压力、施加的压力和热流密度以及最大槽高对有效接触热阻和热整流水平的影响。结果表明,考虑间隙填充剂的力学效应会导致较低的热整流水平。同时,间隙填料导热系数的变化比其压力的变化影响更为显著。
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引用次数: 0
A Framework to Facilitate Firebrand Characterization 促进火种表征的框架
IF 2.3 Q2 ENGINEERING, MECHANICAL Pub Date : 2019-07-12 DOI: 10.3389/fmech.2019.00043
F. Hedayati, Babak Bahrani, Aixi Zhou, S. Quarles, Daniel J. Gorham
Generation of firebrands from various fuels has been well studied in the past decade. Limited details have been released about the methodology for characterizing firebrands such as the proper sample size and the measurement process. This study focuses on (1) finding the minimum required sample size to represents the characteristics of the population, and (2) proposes a framework to facilitate the tedious measurement process. To achieve these goals, several firebrand generation tests were conducted at a boundary layer wind tunnel with realistic gusty wind traces. Firebrands were generated from burning structural fuels and collected in 46 strategically located water pans. The statistical analysis showed that the minimum required sample size based on the chosen statistical parameters (standard deviation, confidence interval, and margin of error) is 1400 for each test. To facilitate characterizing such a large sample of firebrands, an automated image processing algorithm to measure the projected area of the firebrands was developed, which can automatically detect the edges of the background sheet, rotate the photo if its tilted before cropping, detect edges of firebrands, remove erroneous particles (e.g. ash) and finally measures the projected area. To facilitate the weighing process, a Gaussian process regression was performed to predict the mass based on projected area, traveling distance and wind speed. The model can predict the firebrand mass within 5% error compared to the measurement. This framework and model can provide a probabilistic range of firebrand characteristics over the continuous range of the collection region.
在过去的十年中,人们对各种燃料产生的火焰进行了深入的研究。有限的细节已经发布了表征火焰的方法,如适当的样本量和测量过程。本研究的重点是(1)找到代表总体特征的最小样本量,(2)提出一个框架,以简化繁琐的测量过程。为了实现这一目标,在具有真实阵风痕迹的边界层风洞中进行了多次火种产生试验。燃烧结构性燃料产生火焰,并收集在46个战略位置的水盆中。统计分析表明,基于所选择的统计参数(标准差、置信区间和误差范围),每个测试所需的最小样本量为1400。为了便于对如此大的火种样本进行表征,开发了一种测量火种投影面积的自动图像处理算法,该算法可以自动检测背景片的边缘,在裁剪前对倾斜的照片进行旋转,检测火种边缘,去除错误颗粒(如灰烬),最后测量投影面积。为了便于称重,采用高斯过程回归,根据投影面积、行进距离和风速进行质量预测。该模型预测的火种质量与实测误差在5%以内。该框架和模型可以在收集区域的连续范围内提供火种特征的概率范围。
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引用次数: 9
Reduced Gas-Phase Kinetic Models for Burning of Douglas Fir 花旗松燃烧的还原气相动力学模型
IF 2.3 Q2 ENGINEERING, MECHANICAL Pub Date : 2019-07-09 DOI: 10.3389/fmech.2019.00040
J. Glusman, Kyle E. Niemeyer, Amanda S. Makowiecki, N. Wimer, C. Lapointe, G. Rieker, P. Hamlington, J. Daily
New skeletal chemical kinetic models have been obtained by reducing a detailed model for the gas-phase combustion of Douglas Fir pyrolysis products. The skeletal models are intended to reduce the cost of high-resolution wildland fire simulations, without substantially affecting accuracy. The reduction begins from a 137 species, 4533 reaction detailed model for combustion of gas-phase biomass pyrolysis products, and is performed using the directed relation graph with error propagation and sensitivity analysis method, followed by further reaction elimination. The reduction process tracks errors in the ignition delay time and peak temperature for combustion of gas-phase products resulting from the pyrolysis of Douglas Fir. Three skeletal models are produced as a result of this process, corresponding to a larger 71 species, 1179 reaction model with less than 1% error in ignition delay time compared to the detailed model, an intermediate 54 species, 637 reaction model with 24% error, and a smaller 54 species, 204 reaction model with 80% error. Using the skeletal models, peak temperature, volumetric heat release rate, premixed laminar flame speed, and diffusion flame extinction temperatures are compared with the detailed model, revealing an average maximum error in these metrics across all conditions considered of less than 1% for the larger skeletal model, 10% for the intermediate model, and 24% for the smaller model. All three skeletal models are thus sufficiently accurate and computationally efficient for implementation in high-resolution wildland fire simulations, where other model errors and parametric uncertainties are likely to be greater than the errors introduced by the reduced kinetic models presented here.
通过还原花旗松热解产物气相燃烧的详细模型,得到了新的骨架化学动力学模型。骨骼模型的目的是降低高分辨率野火模拟的成本,而不会严重影响准确性。还原从137种4533种气相生物质热解产物燃烧反应详解模型出发,采用误差传播有向关系图和灵敏度分析法进行还原,然后进一步进行反应消去。还原过程跟踪了花旗松热解气相产物燃烧的点火延迟时间和峰值温度的误差。根据这一过程得到了三个骨架模型,分别对应点火延迟时间误差小于1%的较大的71种1179反应模型、误差24%的中等54种637反应模型和误差80%的较小54种204反应模型。使用骨架模型,峰值温度,体积热释放率,预混层流火焰速度和扩散火焰熄灭温度与详细模型进行了比较,揭示了在所有条件下这些指标的平均最大误差:大型骨架模型小于1%,中间模型小于10%,较小模型小于24%。因此,所有三种骨骼模型在高分辨率野火模拟中都具有足够的准确性和计算效率,其中其他模型误差和参数不确定性可能大于本文介绍的简化动力学模型所带来的误差。
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引用次数: 7
Effect of Canyons on a Fire Propagating Laterally Over Slopes 峡谷对火灾在斜坡上横向传播的影响
IF 2.3 Q2 ENGINEERING, MECHANICAL Pub Date : 2019-07-05 DOI: 10.3389/fmech.2019.00041
A. Rodrigues, Carlos Ribeiro, J. Raposo, D. Viegas, J. André
In this paper the problem related with a fire front propagating laterally on a slope with a nearby canyon is presented. The presence of the canyon can modify the intensity of the fire and create a difficult situation for elements involved in fire suppression. When a fire propagating laterally in a slope enters in the canyon, a rapid increase in the fire’s rate of spread occurs and a strong convective activity is generated due to the burning inside the canyon. The convective flow generated will then induce a change in the propagation of the fire in the slope. In certain conditions the rate of spread and the intensity of the fire will be strongly increased. This type of extreme fire behaviour is referred to as eruptive fire behaviour (or blow-up) and usually happens over slopes or in canyon configurations. In this study, we analysed the results of laboratory-scale experiments that model a fire spreading latterly over a slope and then enter a canyon that is embedded in the slope. Three configuration parameters were used in the experiments. The first is the inclination  of the slope, the second is the orientation of the axis of the canyon and the third is the angle  of the ignition line. The fire spread is very complex and dynamic resulting in situations in which very high values of the ROS can be reached for several configurations, creating dangerous situations for firefighters.
本文研究了火灾锋面在附近有峡谷的斜坡上横向传播的问题。峡谷的存在可以改变火灾的强度,给参与灭火的人员创造一个困难的局面。当在斜坡上横向传播的火灾进入峡谷时,由于峡谷内的燃烧,火灾的蔓延速度迅速增加,并产生强烈的对流活动。所产生的对流流将引起火灾在斜坡上传播的变化。在某些情况下,蔓延的速度和火灾的强度将大大增加。这种极端的火灾行为被称为喷发式火灾行为(或爆炸),通常发生在斜坡或峡谷结构中。在这项研究中,我们分析了实验室规模的实验结果,这些实验模拟了一场大火在斜坡上蔓延,然后进入嵌入斜坡的峡谷。实验中采用了三种构型参数。第一是坡度的倾斜度,第二是峡谷轴线的方位,第三是点火线的角度。火灾蔓延非常复杂和动态,导致几种配置可以达到非常高的ROS值,给消防员带来危险的情况。
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引用次数: 14
Additive Manufacturing With Soft TPU – Adhesion Strength in Multimaterial Flexible Joints 软TPU增材制造——多材料柔性接头的粘接强度
IF 2.3 Q2 ENGINEERING, MECHANICAL Pub Date : 2019-07-03 DOI: 10.3389/fmech.2019.00037
Conor G. Harris, Nicholas J. S. Jursik, Willie E. Rochefort, T. Walker
The adhesion in 3D-printed composites between dissimilar layers was investigated in response to demand for multimaterial prints. Previously, we reported on the thermal properties for printability of thermoplastic polyurethane (TPU) blends~cite{harris001}. Here, we report the qualitative and quantitative adhesion properties between commonly-printed materials, acrylonitrile butadiene styrene (ABS) or acrylonitrile styrene acrylate (ASA), and flexible TPU. ASTM D1002/D3164 lap shear adhesion tests were performed to measure the adhesion strength between the acrylonitrile plastics and TPU, finding values of $4.7~mathrm{MPa}$ between ABS and TPU and $6.4~mathrm{MPa}$ between ASA and TPU. These values are on the same order of magnitude of reported commercial adhesives, suggesting that multimaterial 3D printing can provide an automated, industrially-relevant alternative to handmade fabrication. SEM images are reported to show the quality of adhesion between materials in the composites. These images expose qualitative differences in the interlayer adhesion between materials in the composites that depend on the textit{order of printing}. Thermal (DSC and TGA) and rheological characterizations were performed to investigate the processing conditions of the extruded plastics while they are in their melt states. The role of viscosity is shown to have major implications on the adhesion, as materials with lower viscosities displayed improved filling of the interlayer voids and increased strength of adhesion.
为了满足多材料打印的需求,研究了3d打印复合材料中不同层之间的粘附性。以前,我们报道了热塑性聚氨酯(TPU)共混物的可打印性的热性能cite{harris001}。在这里,我们报告了常用印刷材料,丙烯腈-丁二烯-苯乙烯-苯乙烯(ABS)或丙烯腈-苯乙烯-丙烯酸酯(ASA)与柔性TPU之间的定性和定量粘附性能。采用ASTM D1002/D3164搭接剪切粘接试验测定丙烯腈塑料与TPU的粘接强度,得到ABS与TPU的粘接强度为$4.7~mathrm{MPa}$, ASA与TPU的粘接强度为$6.4~mathrm{MPa}$。这些数值与报道的商业粘合剂的数量级相同,这表明多材料3D打印可以为手工制造提供自动化的工业相关替代方案。SEM图像显示了复合材料中材料之间的粘附质量。这些图像揭示了复合材料中材料之间层间附着力的定性差异,这取决于textit{印刷顺序}。热(DSC和TGA)和流变学表征研究了挤出塑料在熔体状态下的加工条件。粘度的作用对粘附性有重要影响,因为具有较低粘度的材料显示出层间空隙的填充改善和粘附强度的增加。
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引用次数: 28
Physics-Based Simulation of Heat Load on Structures for Improving Construction Standards for Bushfire Prone Areas 基于物理的结构热负荷模拟提高森林火灾易发地区建筑标准
IF 2.3 Q2 ENGINEERING, MECHANICAL Pub Date : 2019-06-28 DOI: 10.3389/fmech.2019.00035
Nazmul Khan, D. Sutherland, R. Wadhwani, K. Moinuddin
Australian building standard AS 3959 provides mandatory requirements for the construction of buildings in bushfire prone areas in order to improve the resilience of the building to radiant heat, flame contact, burning embers, and a combination of these three bushfire attack forms. The construction requirements are standardised based on the bushfire attack level (BAL). BAL is based on empirical models which account for radiation heat load on structure. The prediction of the heat load on structure is a challenging task due to many influencing factors: weather conditions, moisture content, vegetation types and fuel loads. Moreover, the fire characteristics change dramatically with wind velocity leading to buoyancy or wind dominated fires that have different dominant heat transfer processes driving the propagation of the fire. The AS 3959 standard is developed with respect to a quasi-steady state model for bushfire propagation assuming a long straight line fire. The fundamental assumptions of the standard are not always valid in a bushfire propagation. In this study, physics based large-eddy simulations were conducted to estimate the heat load on a model structure. The simulation results are compared to the AS 3959 model; there is agreement between the model and the simulation, however, due to computational restrictions the simulations were conducted in a much narrower domain. Further simulations were conducted where wind velocity, fuel load, and relative humidity are varied independently and the simulated radiant heat flux upon the structure was found to be significantly greater than predicted by the AS 3959 model. The effect of the mode of fire propagation, either buoyancy-driven or wind dominated fires, is also investigated. For buoyancy dominated fires the radiation heat load on the structure is enhanced compared to the wind dominated fires. Finally, the potential of using physics based simulation to evaluate individual designs is discussed.
澳大利亚建筑标准AS 3959为森林火灾易发地区的建筑提供了强制性要求,以提高建筑物对辐射热、火焰接触、燃烧余烬以及这三种森林火灾攻击形式的组合的恢复能力。建筑要求是根据森林火灾攻击等级(BAL)进行标准化的。BAL基于考虑结构辐射热负荷的经验模型。由于天气条件、水分含量、植被类型和燃料负荷等因素的影响,结构热负荷的预测是一项具有挑战性的任务。此外,火灾特征随风速变化显著,导致浮力或风主导火灾,它们具有不同的主导传热过程驱动火灾的传播。AS 3959标准是针对假定长直线火灾的森林火灾传播的准稳态模型而制定的。标准的基本假设在森林火灾传播中并不总是有效的。在本研究中,采用基于物理的大涡模拟来估计模型结构的热负荷。仿真结果与AS 3959模型进行了比较;模型与仿真结果是一致的,但由于计算的限制,模拟的范围要窄得多。在风速、燃料负荷和相对湿度独立变化的情况下进行了进一步的模拟,发现模拟的结构辐射热通量明显大于AS 3959模型的预测值。此外,还研究了浮力驱动或风力主导的火灾传播方式的影响。对于浮力主导的火灾,结构的辐射热负荷比风主导的火灾增强。最后,讨论了使用基于物理的仿真来评估单个设计的潜力。
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引用次数: 12
Condensation on Surfaces With Biphilic Topography: Experiment and Modeling 双亲性表面上的凝结:实验与模拟
IF 2.3 Q2 ENGINEERING, MECHANICAL Pub Date : 2019-06-25 DOI: 10.3389/fmech.2019.00038
Elaheh Alizadeh-Birjandi, A. Alshehri, H. Kavehpour
Optimization of the efficiency of the condensers via different surface engineering techniques is a subject of interest due to its wide range of application in thermal management for aerospace vehicles, power generation systems, and etc., which will further result in considerable savings in annual investments and operating costs by millions of dollars. However, the current technologies are lacking either the necessary condensation enhancements or cost-effective, large-scale fabrication method. In this work, we present a new surface topography to enhance drop-wise condensation at low manufacturing costs. These surfaces consist of macro-scale hydrophobic patterns on hydrophilic structures. Due to their high wettability contrast, the biphilic surfaces enhance drop-wise condensation with long-term functionality, and more importantly, they can be easily manufactured in large-scale using conventional methods as no nano- or micro-features are needed.
通过不同的表面工程技术优化冷凝器的效率是一个令人感兴趣的主题,因为它广泛应用于航空航天飞行器、发电系统等的热管理,这将进一步节省数百万美元的年度投资和运营成本。然而,目前的技术既缺乏必要的冷凝增强,也缺乏成本效益高的大规模制造方法。在这项工作中,我们提出了一种新的表面形貌,以提高低制造成本的滴状冷凝。这些表面由亲水性结构上的宏观疏水图案组成。由于它们的高润湿性对比,双亲性表面增强了具有长期功能的滴状冷凝,更重要的是,它们可以很容易地使用常规方法大规模制造,因为不需要纳米或微特征。
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引用次数: 8
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Frontiers in Mechanical Engineering
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