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关键词： 周期拓扑   流动损失   定量预测   数学模型   数值模拟  

摘要： 对能源转换系统中的流动损失进行准确评估有助于提高系统能效优化的效率。针对具有周期性规则拓扑的扰流结构,提出了一种可用于定量分析和预测流动损失的完备数学模型。以常见的错排短柱阵列为例,详细阐述了模型的建立方法,以及如何基于所建立的指数型经验方程对流动损失进行定量的因素分析。为此,建立了一套采用对称和周期边界的数值方法,用于高效收集模型建立所需的基础数据。研究结果表明,数学模型中特定结构或流动参数对应指数的绝对值可表征其对流动损失的定量影响。该模型具有较高的普适性,可用于具有类似拓扑特征和任意数量影响因素的扰流结构流动损失分析和预测。

关键词： 流体包裹体   成藏期次   均一温度   火山岩储层   石炭系   车排子凸起  

摘要： 为了深入认识车排子地区石炭系火山岩油藏的形成过程,文中对8口探井28块样品进行了流体包裹体与盆地模拟分析。流体包裹体岩相学、热力学分析表明:该区石炭系火山岩储层发育2类烃类包裹体,第1类充填于方解石、方沸石脉中成群分布,伴生盐水包裹体均一温度主峰值为80~90℃,具有高盐度、低主频均一温度特征;第2类充填于石英颗粒斑晶和切穿石英颗粒的微裂隙中成带分布,伴生盐水包裹体均一温度主峰值为120~130℃,具有低盐度、高主频均一温度特征。结合红车断裂带启闭性演化及烃源岩热演化史,明确了石炭系具有2期成藏过程,成藏时间分别为古近纪末和新近纪末,均为早期形成的油藏调整改造与再次运移聚集而形成。

关键词： 微观孔隙结构   可动流体   核磁共振   腾格尔组   二连盆地  

摘要： 为了明确二连盆地阿尔凹陷腾格尔组腾一下段储层微观孔隙结构和可动流体赋存特征,开展了扫描电镜、铸体薄片、X射线衍射、高压压汞、恒速压汞和核磁共振等实验研究。结果表明:①腾一下段储层微观孔隙结构分为3种类型,不同孔隙结构具有不同的可动流体赋存特征。②Ⅰ类大孔喉结构,孔喉组合主要为粒间孔-孔隙缩小型喉道和粒间孔-缩颈型喉道,喉道半径大,孔喉半径比小,核磁共振T2谱主要为左低右高双峰型,可动流体饱和度高;Ⅱ类孔隙结构,主要为粒间孔-片状喉道组合与溶蚀孔-片状喉道组合,T2谱主要为左高右低双峰型,可动流体饱和度中等;Ⅲ类孔隙结构,主要为粒间孔-片状喉道组合、溶蚀孔-片状喉道组合和晶间孔-管束状喉道组合,喉道半径小,T2谱为左单峰型,可动流体饱和度低。③储层物性、微观孔隙结构、黏土矿物含量对可动流体赋存具有重要影响,其中喉道特征是影响可动流体赋存的最主要因素,喉道半径越大,大喉道越多,可动流体饱和度越高。该研究成果对阿尔凹陷腾一下段储层的高效开发具有指导意义。

关键词： 吹泡泡   表面张力   普拉托-瑞利不稳定性   CUPT  

摘要： 对圆环中的皂液薄膜吹气可以得到"泡泡",用高速摄像机记录了泡泡的产生过程,结合普拉托-瑞利不稳定性理论对该过程进行了理论和实验研究,定量得出了泡泡大小和泡泡产生速率的规律。

关键词： 润湿性   液体粘度   表面张力   流体动力学   液滴撞击  

摘要： 利用相界面追踪的耦合水平集-流体体积(CLSVOF)方法,对液滴撞击超疏水管状壁面的动态特性展开研究,主要讨论粘性系数和表面张力系数对撞击过程的影响。研究结果表明:液滴粘性系数越小,液膜的铺展速度越快,回缩速度也越快,同时越早发生反弹,反弹高度也越大;随着表面张力系数的增大,液膜达到最大铺展所需时间减少,会阻碍液膜的铺展,但会促进其回缩,当表面张力系数为0.01 N/m时,液膜外边缘出现飞溅且液膜主体不发生反弹;还对液滴撞击超疏水管壁后出现的反弹、飞溅现象的机理展开分析。

关键词： 表面张力   氧化安定性   酸值   预测模型  

摘要： 采用Rancimat法在110℃下对小桐子生物柴油进行不同时间的加速氧化降解,利用GC-MS技术、酸值滴定等手段研究了用表面张力检测燃料氧化程度的适用性。通过对实验数据分析表明:小桐子生物柴油经加速氧化后生成醛、酮、相对分子质量较高的含氧化合物及可溶性聚合物;其表面张力、酸值以及密度在氧化14 h后分别增加了9.1%、551%和3.8%;经相关性分析得到氧化后小桐子生物柴油表面张力与酸值的相关系数为0.99。基于此提出了4种利用表面张力预测小桐子生物柴油氧化程度的模型,并采用留一交叉验证法进行了检验分析,通过比较均方根误差(RMESP)值、相关系数R值,最终确定对数模型精确度以及相关性较高,其RMESP值以及相关系数R值分别为0.0937、0.9879,并且酸值预测值与实际值的误差为2.95%,说明通过表面张力可以预测小桐子生物柴油的氧化程度。

关键词： Two-fluid model   Sound field   Geldart-A particles   Microscopic flow characteristics   Macroscopic flow characteristics  

摘要： Sound field assisted fluidized bed is a promising approach to regulate particle behaviors in gas-solid two-phase flows. In this study, an acoustic model was built and coupled with Euler-Euler two-fluid model to study macroscopic and microscopic flow characteristics of Geldart-A particles. The influence of acoustic frequencies and sound pressure levels on particle behavior was analyzed. The sound field has little influence on the macroscopic flow characteristics of the particles, but a significant influence on the microscopic characteristics. With the increasing acoustic frequencies and sound pressure levels, the bubble granular temperature at the top of the fluidized bed decreases, and the periodicity of it is becoming irregular. Particle granular temperature increases with the increasing acoustic frequencies and sound pressure levels. In the near wall region, the sound field affected the particles to a smaller extent. This study provides a reference for exploring the sound-field regulation of particles and bubble behaviors.

关键词： Radiation heat transfer   Non-gray radiation   Oxy-fuel combustion   Pressurized fluidized bed  

摘要： The thermal radiation transfer was complex due to high pressure, complicated flue gas components and abundant particles in the dilute phase region of oxy-fuel combustion pressurized fluidized bed. To carry out the radiation heat transfer, numerical simulations were done based on weighted sum of gray gases model (WSGG) and Mie theory. The Radiation Transfer Equations (RTE) of bubbling fluidized bed and circulating fluidized bed was solved by discrete ordinate method (DOM). The radiation heat transfer of fluidized bed under air combustion was verified and then the simulations were accomplished under pressurized oxy-fuel combustion hypothesis. The results revealed that the particle radiation was still dominant under pressurized oxy-fuel combustion. The change of total pressure and gas composition had slight effects on the radiation heat transfer in the fluidized bed. The gas radiation described by the new pressurized WSGG model and RTE solving by body-fitted coordinate system were much accurate to simulate radiation heat transfer. All the results were significant to provide theoretical basis of designing and building an oxy-fuel combustion pressurized fluidized bed.

关键词： deep learning   self-organizing maps   non-Hodgkin lymphoma  

摘要： The wealth of information captured by multiparameter flow cytometry (MFC) can be analyzed by recent methods of computer vision when represented as a single image file. We therefore transformed MFC raw data into a multicolor 2D image by a self-organizing map and classified this representation using a convolutional neural network. By this means, we built an artificial intelligence that is not only able to distinguish diseased from healthy samples, but it can also differentiate seven subtypes of mature B-cell neoplasm. We trained our model with 18,274 cases including chronic lymphocytic leukemia and its precursor monoclonal B-cell lymphocytosis, marginal zone lymphoma, mantle cell lymphoma, prolymphocytic leukemia, follicular lymphoma, hairy cell leukemia, lymphoplasmacytic lymphoma and achieved a weighted F1 score of 0.94 on a separate test set of 2,348 cases. Furthermore, we estimated the trustworthiness of a classification and could classify 70% of all cases with a confidence of 0.95 and higher. Our performance analyses indicate that particularly for rare subtypes further improvement can be expected when even more samples are available for training. (c) 2020 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of International Society for Advancement of Cytometry.

关键词： Supersonic flow   Parachute   Shock wave   Pressure fluctuation  

摘要： The supersonic wind tunnel tests using a rigid parachute model were conducted for Mach numbers ranging from 2.0 to 3.0. The rigid model consists of suspension lines and a riser between the forebody and rear body, and the effect of these suspension lines was investigated. Three characteristic flow modes, namely, high-pressure, low-pressure, and attachment modes, were observed. These three modes were classified on the basis of the shape and position of the apex of the shock wave. In addition, the non-dimensional pressure observed at the center of the canopy varied according to the pressure mode produced. The emergence of each pressure mode depended on the parameters, namely, freestream Mach number, trailing distance, and distance between the bundling point and rear body. Pressure-mode transitions were observed when specific conditions and configuration of the parameters were achieved. (C) 2020 Elsevier Masson SAS. All rights reserved.