The Description of Oil Displacement Mechanism in Steam Injection of Multi-Field Synergy with Exergy Transfer

Steam injection is a most effective way for improving heavy oil recovery efficiency, and it has academic and practical significance for the mechanism of multi-field synergy oil displacement. Mechanism of “diversified” oil displacement which is obtained by traditional study methods in the exploitation territory of oil and gas fields has both respective roles and mutual cross shortages. To describe and analyze the displacement process of multi-field coupling with exergy transfer can simplify this kind of problem by introducing a unified goal-driving exergy. It needs to use the method of theoretical modeling, numerical simulation and experimental validation to study the basic law of exergy transfer in the oil displacement process of multi-field synergy, make a thorough research for the flooding process of steam injection with exergy transfer theory and reveal the oil displacement mechanism in steam injection of multi-field synergy. Thus the theory instruction and technical support can be provided to improve reservoirs producing degree and extraction ratio.

Heat Transfer and Resistance Characteristics of Conical Spiral Tube Bundle Based on Field Synergy Principle

Conical spiral tube bundle are universally used in heat transfer enhancement in heat exchangers.The heat transfer and resistance of the tube bundle are affected greatly by the conical structure,so the analysis of it is necessary.In order to a further evaluation,the heat transfer and resistance characteristics of conical spiral tube bundle are investigated with regression analysis based on numerical simulation data.The correlations of heat transfer and pressure drop of conical spiral tube bundle are proposed both in laminar and turbulent fluid flow.On the based of the field synergy principle,the synergy of four vectors,the velocity,the velocity gradient,the temperature gradient and the pressure gradient,are calculated and discussed via the user defined function（UDF） program.The synergy angles β and θ,which respectively denote the performance of heat transfer enhancement and pressure drop of the conical spiral tube bundle,are analyzed.Finally,the comprehensive performance of the conical spiral tube is evaluated by the synergy angle γ and all of the three synergy angles of conical spiral tube bundle are compared to both bare tube and thin cylinder-interpolated tube.The analysis of the synergy angles shows that the heat transfer enhancement and pressure drop of conical spiral tube bundle are smaller than that of the thin cylinder-interpolated tube,while the comprehensive performance of conical spiral tube bundle is greater.The analysis of the heat transfer and pressure drop of conical spiral tube is valuable and instructional on the design and optimum of conical spiral tube bundle heat exchangers.

Heat Transfer Enhancement with Mixing Vane Spacers Using the Field Synergy Principle

The single-phase heat transfer characteristics in a PWR fuel assembly are important. Many investigations attempt to obtain the heat transfer characteristics by studying the flow features in a 5 x 5 rod bundle with a spacer grid. The field synergy principle is used to discuss the mechanism of heat transfer enhancement using mixing vanes according to computational fluid dynamics results, including a spacer grid without mixing vanes, one with a split mixing vane, and one with a separate mixing vane. The results show that the field synergy principle is feasible to explain the mechanism of heat transfer enhancement in a fuel assembly. The enhancement in subchannels is more effective than on the rod＇s surface. If the pressure loss is ignored, the performance of the split mixing vane is superior to the separate mixing vane based on the enhanced heat transfer. Increasing the blending angle of the split mixing vane improves heat transfer enhancement, the maximum of which is 7.1%. Increasing the blending angle of the separate mixing vane did not significantly enhance heat transfer in the rod btmdle, and even prevented heat transfer at a blending angle of 50%. This fmding testifies to the feasibility of predicting heat transfer in a rod bundle with a spacer grid by field synergy, and upon comparison with analyzed flow features only, the field synergy method may provide more accurate guidance for optimizing the use of mixing vanes.

Characterizing the catalyst fluidization with field synergy to improve the amine absorption for CO2 capture

There are great interests to capture the CO2 to control the greenhouse gas emission.Amine absorption of CO2 is being taken as an effective way to capture CO2 in industry.However,the amine absorption of CO2 is cost-ineffective due to great energy consumption and solution consumption.In order to reduce the capture cost,catalyst fluidization is proposed here to intensify the mass transfer and heat transfer.Catalyst fluidization with field synergy and DFT model is developed by incorporating the effects of catalyst reaction kinetics,drag force and multi-field into the mass transfer,heat transfer,fluid flow and catalyst collision.Experiments with an improved distributor are performed well to validate the model.The reaction kinetics is determined by the DFT simulation and experiment.The mass transfer coefficient in the fluidized reactor is identified as 17%higher than the conventional packed reactor.With the field synergy of catalyst fluidization,the energy consumption for CO2 desorption is reduced by 9%.Stepwise operation and inclination reactor are used to improve catalyst fluidization process.

Entransy dissipation analysis of interfacial convection enhancing gas–liquid mass transfer process based on field synergy principle

An exploration of the gas CO2 absorbed into liquid ethanol accompanied with Rayleigh convection is performed by analyzing the mass entransy dissipation;this new statistical quantity is introduced to describe the irreversibility of mass transfer potential capacity. Based on the general advection–diffusion differential equation for an unsteady mass transfer process, the variation of the included angle between the velocity vector and concentration gradient fields is investigated to reveal the underlying mechanism of interfacial convection enhancing mass transfer. Results show some identical characteristics with the qualitative analyses of the synergy effects generated by the concentration and velocity fields after interfacial convection occurring for a boundary condition of fixed surface concentration. And the equivalent mass resistance for convective mass transfer process presents the similar variation with the reciprocal of instantaneous mass transfer coefficient. Accordingly, it is reasonable to be seen that mass transfer dissipation rate could be provided to assess the convection strength and explain fundamentally how Rayleigh convection improves mass transfer performance through establishing a close relationship between the mass transfer capacity and field synergy principle from the view of mass transfer theory.

Performance evaluation on field synergy and composite regeneration by coupling cerium-based additive and microwave for a diesel particulate filter

In order to reveal the mechanics of composite regeneration by coupling cerium-based additive and microwave for a diesel particulate filter, a composite regeneration model by coupling cerium-based additive and microwave for a diesel particulate filter was established based on field synergy theory. Performance evaluation on field synergy and composite regeneration of the diesel particulate filter was conducted by using the vortex crushing combustion and field synergy mathematical models. The results show that the peak temperature of the particulate filter body reaches 1180-1190 K when the regeneration time is 175 s, and there are optimal coordination degree between the velocity vector and temperature gradient of the filter body and the maximum ratio0.56-0.60 of the best burning regeneration region is obtained. Accordingly, the largest regeneration combustion rate inside the particulate filter body and the highest regeneration efficiency at the moment are achieved.

煤田震电协同勘探技术研究与应用

近年来煤田震电协同勘探技术在设计、处理分析方面都取得了较大的发展,从采区最常使用的三维地震勘探、瞬变电磁勘探方法入手,对采集到的各种数据运用主成分分析(PCA)进行融合处理,解译煤矿采区工作面的异常地质体及富水性等隐蔽致灾因素。该技术实现了三维地震、瞬变电磁勘探在数据层面的综合勘探,提高了物探解释煤矿采区工作面地质异常体(富水性)的准确性,为震电协同勘探技术体系的构建提供了新思路,为煤矿安全、高效、绿色生产提供了保障。

绿色水处理药剂的合成及其与静电场协同性能研究

采用不含磷氮的药剂衣康酸(IA)和甲基丙烯磺酸钠(SMAS)合成了环保型的两元共聚物药剂,并系统研究了合成工艺条件对共聚物性能的影响。最终得到最佳合成条件如下:原料质量比(IA∶SMAS)为2∶1,聚合温度为95℃,聚合时间为6 h;此外,引发剂和链转移剂的添加量均为原料总质量的5%。经静态阻垢实验研究表明,合成的共聚物具有优异的阻垢性能和分散性能。将该共聚物与静电场结合用于阻垢性能研究,结果表明静电场的存在使IA/SMAS的阻垢性能提高了17%,静电与IA/SMAS共聚物具有协同增效作用。

基于场协同理论的热空气吹掠型太阳能蒸馏器对流传热性能优化分析

以热空气吹掠型太阳能蒸馏器为研究对象,利用数值模拟结果和均匀设计法分析蒸馏器内流动与传热场协同角的变化规律和影响因素。结果表明,影响场协同角的主要因素是热空气进口速度,热空气进口温度和水温的影响不显著。在蒸馏水温30~70℃、进口空气温度40~90℃,进口空气速度为8 m/s时平均传热场协同角最小,为73.14°,传热系数最大,可达到同等条件下自然对流传热系数的4倍。

新质生产力推动下现场工程师培养的内在逻辑与实践进路

新质生产力对职业教育人才培养提出了新要求。马克思主义生产力经典理论和习近平经济思想对分析新质生产力的内涵与特征提供了理论指导。面向先进制造业、战略性新兴产业和未来产业培养现场工程师,是高等职业教育支撑和服务新质生产力发展的本质要求和现实需要。针对当前现场工程师培养存在的供需错位、范式缺失、效能不足等问题,构建量增质升的培养体系、创新生态协同的培养机制及场景化协作学习范式,成为现场工程师培养的实践路径。

基于场协同原理的涡发生器强化撞击流反应器混合性能分析

为了提高撞击流反应器的混合性能,采用数值模拟的方法分析了置入矩形翼涡发生器后撞击流反应器内的流场特性与混合特性,并且优化了矩形翼涡发生器参数。研究了矩形翼涡发生器尺寸参数与位置参数对撞击流反应器混合强度的影响,以及涡发生器位置参数对反应器内速度分布和湍动能分布的影响,运用传质场协同原理分析了设置矩形翼涡发生器和未设置矩形翼涡发生器的撞击流反应器内速度场和浓度场的协同性。结果表明,随着径向间距r的增加混合强度呈现出先增后减的趋势,当翼宽h、转轴间距d和迎流攻角β逐渐增加时混合强度波动变化,在矩形翼涡发生器的翼宽h=10 mm,转轴间距d=8 mm,径向间距r=30 mm,迎流攻角β=30°时,反应器内混合强度最大,得到的混合效果最佳;在两股流体充分撞击的情况下,撞击流反应器内径向射流区域的速度分布呈现为“双峰”分布规律,涡发生器位置参数的改变可以提高径向速度,在转轴间距d=8 mm、迎流攻角β=30°时径向速度最高,反应器内径向射流区域的湍动能分布呈现出“单峰”分布规律,但涡发生器位置参数的变化对于湍动能分布的影响不大;从场协同的角度分析可知,矩形翼涡发生器的加入改变了撞击流反应器内径向射流的速度大小和方向,进而改善了撞击流反应器内速度场与浓度场的协同性,提高了撞击流反应器的混合性能。

气相旋转螺旋槽管式换热器结构优化与性能试验

粮食干燥生产中换热损失大,存在烟气热量无法高效传递,导致换热效率低等问题。本文以集管壳与列管式换热于一体的气相旋转螺旋槽管式换热器为研究对象,基于场协同与热力学理论优化螺旋槽管关键部件,探究螺旋槽管参数对换热性能的影响。以螺距、槽深及内外径比为试验因素,以努塞尔数和阻力系数为评价指标,进行三因素五水平二次正交旋转组合试验,采用多目标优化方法确定最优参数组合,当螺距为24.845 mm、槽深为1.753 mm、内外径比为0.897时,Nu为164.637,f为0.348。对优化结果进行验证试验,试验结果与优化结果基本一致。螺旋槽管平均场协同角β相较于圆管降低约2°,揭示了置于壳程内的螺旋槽管管束进口、出口及中间截面内场协同角的分布特征,整体范围内的场协同效果有所增加,结论符合场协同原理。利用强化换热综合性能指数(Performance evaluation criteria,PEC)进行评价,结果表明气相旋转螺旋槽管式换热器PEC在1.031~1.267之间,验证了螺旋槽管在换热器应用的合理性。

考虑物性变化及壳体传热的新型板壳式换热器板程流动传热数值模拟

板壳式换热器以优越的换热性能和耐温耐压性在化工生产等领域有着广阔的应用前景。本文采用可实现k⁃ε湍流模型结合增强壁面函数,对一种新型板壳式换热器板程流动与传热特性进行数值模拟研究,讨论了介质物性变化及壳体传热的影响,并与已有实验进行验证。重点分析了不同波纹高度在不同入口流速下的流动传热特性,基于场协同理论揭示了速度场与温度场及压强场协同分布规律。结果表明:流动传热计算不能忽略流体介质物性变化及壳体传热的影响;增大波纹高度流态由曲折流向十字交叉流转变,板间流体分布趋于均匀,换热性能增大;沿沟槽形成连续的涡结构,在触点周围形成具有周期性和中心对称的高剪切涡量集中区,垂直于流动方向场协同呈现周期性变化,波纹高度越高周期性越明显;在波纹核心流域内因流动与热流相似,其协同程度变差。

动力电池液冷系统设计及其场协同优化

主要针对纯电动汽车动力电池液冷系统参数进行设计及优化,建立电池组散热模型,对其在不同参数下放电过程中的热分布进行仿真。在热流协同性和冷却效果方面,运用场协同原理对冷却管道中的各个参数进行分析。仿真结果表明,冷却液初始温度、流速和入口分布均会对液冷系统冷却性能产生影响。根据条件设置,冷却液初始温度为15℃与流速为2L/min的液冷系统可有效提高电池组的冷却效果;冷却通道入口为3个时期冷却效果最佳,电池组温差为最小。

场协同拉伸螺杆强化混合与传热机理的研究

基于聚合物场协同塑化输运混炼原理,设计开发强化混合与换热的场协同拉伸螺杆新结构——场协同拉伸元件,利用ANSYS Polyflow对普通双头螺纹螺杆和不同拉伸元件排布的场协同拉伸螺杆进行了数值模拟,对比分析了不同螺杆构型对聚合物胶料的混合性能、传热性能以及塑化均匀性的影响。结果表明,场协同拉伸螺杆综合性能均优于普通螺纹螺杆,其中,场协同拉伸元件集中排布的螺杆B传热性能最优,场协同拉伸元件分散排布的螺杆F混合性能最优;场协同拉伸螺杆中拉伸元件的径向收敛流道改变了速度场的方向,使速度矢量产生了径向分量,促进了速度场与温度梯度场、速度梯度场的协同相互作用,增加流场中的拉伸流动和拉伸形变,强化了热质传递输运过程。

印刷电路板换热器内翅片布置方式的场协同分析与讨论

为了研究超临界CO_(2)的传热性能并提高其换热性能,通过采用超临界CO_(2)作为传热流体,以翼型翅片为例,使用数值模拟的方法探究印刷电路板换热器内的不连续翅片通道,分析几种翅片布置方式的传热和阻力性能,得出翅片的最佳布置方式。同时通过场协同理论,即通过分析温度场、压力场和速度场之间的协同性对模拟结果进行分析与讨论。结果表明,当交错距离为4 mm时,其传热性能与阻力性能均为最优,拥有最小的温度场与速度场协同角和最大的压力场与速度场协同角,表明这种布置方式可以使温度场与速度场的协同性和压力场与速度场的协同性均为最优,且它们之间的协同性均随着入口质量流量的增大而变差。

竖直波纹流道内超临界氮气流动与传热研究

本工作开展了不同质量流速[G=200~400 kg/(m^(2)·s)]、热流密度(q=200~400 kW/m^(2))和系统压力(P=5~7 MPa)对超临界氮气在竖直波纹流道内流动与传热特性影响的研究,分析了局部对流换热系数和周期平均对流换热系数分布特性,结合场协同原理和浮升力效应分析不同竖直流向之间对流换热系数差异产生的主要原因。结果表明,波纹周期内局部对流换热系数存在波动;周期平均对流换热系数能更好地反映超临界氮气在流道内的整体流动换热特性。提高质量流速可以显著增强换热,削弱流向对换热系数的影响;增加热流密度会降低流道内换热系数,强化流向对换热系数的影响;系统压力接近临界压力会提高流道内换热系数峰值,不同流向换热系数差异受系统压力影响较小;波纹流道内不同流向对流换热系数差异主要是由浮升力效应和场协同效应共同影响产生的。

场协同扭转螺杆对胶料挤出性能的影响规律

利用ANSYS Polyflow软件对普通螺纹螺杆和具有不同分割棱倾角的场协同扭转螺杆进行了非等温瞬态流动模拟,分析了不同螺杆构型对胶料混合、传热和塑化均匀性等挤出性能的影响规律。结果表明,场协同扭转螺杆综合性能普遍优于普通螺纹螺杆,其中以分割棱倾角为45°的螺杆为最优;场协同扭转螺杆引起的螺旋流动改善了胶料速度场、速度梯度场与温度梯度场之间的协同作用,加强了混合与换热,提高了胶料的塑化质量。

“风光热储”多能协同的智慧油气田发展研究

在“双碳”目标、新型能源体系建设的背景下,化石能源与风能、太阳能、地热能等新能源的融合发展与智慧调控成为未来能源体系发展的新模式;油气行业正在开展数字化、智能化转型,发展智慧油气田将降低勘探开发成本、增加社会和经济效益。本文阐述了多能协同的智慧油气田理念与内涵,新型智慧油气田对油气增储上产,油气行业绿色、低碳、智能化转型的关键推动作用;递次梳理了“风光热储”多能协同系统、油气田与“风光热储”多能协同系统融合、智慧油气田等的发展现状,凝练了我国智慧油气田发展面临的挑战和关键问题;总结了未来“风光热储”多能协同的智慧油气田场景:智慧油气田绿电利用、废弃稠油热采油藏的新地热系统、基于风/光发电微网的抽油井群生产运行优化、天然气就地转化与油田伴生气发电利用、高效低碳油气生产综合能源管控系统、电/热/氢储能智能协同优化。“风光热储”多能协同的智慧油气田建设的核心产出是低碳油气田及超级能源盆地,需在保障油气产量的前提下,围绕“补充基础短板-增加技术优势-强化应用能力-实现自主可控”发展主线,突破关键核心技术,形成实用发展方案。

橡胶挤出加工过程中热管理问题研究进展

分析了橡胶挤出过程中热问题产生的原因及不利影响,从螺杆结构优化、外部冷却和内部传热强化及场协同原理在强化传热领域的应用等方面综述了近年来国内外橡胶挤出加工过程中热管理的研究现状,对橡胶挤出加工过程中热管理的发展方向进行了展望。