Expressions for Entropy Production Rate of Fuel Cells

根据燃料房间的一个一般模型，在不同条件下面的一个燃料房间系统的熵生产率被使用电气化学和热力学的理论导出。以便分析在一个实际燃料房间存在的不可逆的损失的影响，燃料房间的相等的电路被介绍以便燃料房间的不可逆的因素可能作为功能直接坚定内部，漏缝和负载电阻。而且，燃料房间的最大的力量产量和效率被计算，燃料房间的最佳的操作被讨论，并且负担抵抗的匹配的条件是坚定的。

ENTROPY PRODUCTION RATE OF THE MINIMAL DIFFUSION PROCESS

The entropy production rate of stationary minimal diffusion processes with smooth coefficients is calculated. As a byproduct, the continuity of paths of the minimal diffusion processes is discussed, and that the point at infinity is absorbing is proved.

Entropy Production Rate Changes in Lysogeny/Lysis Switch Regulation of Bacteriophage Lambda

According to the chemical kinetic model of lysogeny/lysis switch in Escherichia coli (E.coli) infected by bacteriophage λ,the entropy production rates of steady states are calculated.The results show that the lysogenic state has lower entropy production rate than lytic state,which provides an explanation on why the lysogenic state of λ phage is so stable.We also notice that the entropy production rates of both lysogenic state and lytic state are lower than that of saddle-point and bifurcation state,which is consistent with the principle of minimum entropy production for living organism in nonequilibrium stationary state.Subsequently,the relations between CI and Cro degradation rates at two bifurcations and the changes of entropy production rate with CI and Cro degradation are deduced.The theory and method can be used to calculate entropy change in other molecular network.

Entropy Production Rate for Avascular Tumor Growth

The entropy production rate was determined for avascular tumor growth. The proposed formula relates the fractal dimension of the tumor contour with the quotient between mitosis and apoptosis rate, which can be used to characterize the degree of proliferation of tumor cells. The entropy production rate was determined for fourteen tumor cell lines as a physical function of cancer robustness. The entropy production rate is a hallmark that allows us the possibility of prognosis of tumor proliferation and invasion capacities, key fac-tors to improve cancer therapy.

Experimental Study on Performance of Supercritical CO_2 Heat Exchanger with Four Different Inner Tubes

The experiment was conducted to investigate the heat transfer performance of supercritical CO_2 in a casing heat exchanger by comparing their heat transfer,entropy production unit number,non-dimensional entropy production rate and field synergy factor.The results show that both heat transfer and entropy production unit number in four tubes decrease with water temperature increasing.Heat transfer and entropy production unit number in multiple tubes( i. e.,triple straight tube and double helix tube) is higher than their single counterparts; the non-dimensional entropy production rate increases with water temperature. Non-dimensional entropy production rate of triple straight tube and double helix tube is far below the single tube. Field synergy factor of double helix tube is much higher than that of the triple straight tube under the same condition. Further experiment was carried out in double helix tube,under various CO_2 pressure and inlet water temperature,the results are analyzed and reported in this paper.

Second Law Analysis and Optimization of Elliptical Pin Fin Heat Sinks Using Firefly Algorithm

One of the most significant considerations in the design of a heat sink is thermal management due to increasing thermal flux and miniature in size.These heat sinks utilize plate or pin fins depending upon the required heat dissipation rate.They are designed to optimize overall performance.Elliptical pin fin heat sinks enhance heat transfer rates and reduce the pumping power.In this study,the Firefly Algorithm is implemented to optimize heat sinks with elliptical pin-fins.The pin-fins are arranged in an inline fashion.The nature-inspired metaheuristic algorithm performs powerfully and efficiently in solving numerical global optimization problems.Based on mass,energy,and entropy balance,three models are developed for thermal resistance,hydraulic resistance,and entropy generation rate in the heat sink.The major axis is used as the characteristic length,and the maximum velocity is used as the reference velocity.The entropy generation rate comprises the combined effect of thermal resistance and pressure drop.The total EGR is minimized by utilizing the firefly algorithm.The optimization model utilizes analytical/empirical correlations for the heat transfer coefficients and friction factors.It is shown that both thermal resistance and pressure drop can be simultaneously optimized using this algorithm.It is demonstrated that the performance of FFA is much better than PPA.

Study on S-shaped region of pump turbine based on Omega vortex analysis method and entropy production theory

In order to comprehensively analyze the operation instability of the pump turbine S-shaped region,this paper uses DDES turbulence model to calculate the model pump turbine from the perspective of the evolution law of runner vortex and draft tube vortex rope and entropy production rate,combined with experiments.The results show that the numerical simulation is in good agreement with the experiment.Omega vortex analysis method is more accurate than other vortex recognition methods because it is not affected by the threshold value.The vortices at the runner region under the runaway condition and the turbine brake condition develop towards the vaneless space and the blade pressure surface respectively,which will cause the flow obstruction and blade separation.The overall vorticity of the reverse pump condition is the largest.The vortex rope of the draft tube under runaway and turbine brake conditions is columnar in shape and has very high rotational strength.The vortex rope under reverse pump conditions is prone to fracture and form scattered vortices,impeding the normal movement of the fluid.The entropy production rate of the spanwise surface near the upper ring and the lower crown is greater than the middle spanwise surface due to the boundary layer effect.And the energy dissipation in the runner under reverse pump conditions is characterized by high at both ends of the runner and low in the middle.The energy dissipation near the wall of the straight cone section of the draft tube is large due to the squeezing effect of the vortex rope on the flow.

Characteristics of geothermal field and evaluation of geothermal resource potential in the Yingjiang Basin

Geothermal resource,a green and sustainable energy resource,plays an important role in achieving‘emission peak’and‘carbon neutrality’targets.The Yingjiang Basin is located in the eastern branch of the Mediterranean-Himalayan high-temperature geothermal belt and exhibits considerable potential for geothermal resources.However,current investigations into the distribution of deep geothermal resources in this region are somewhat limited.In this paper,the transient plane source(TPS)method is used to measure the thermal conductivity parameters of 31 rock samples within the study area.Additionally,the one-dimensional steady-state heat conduction equation is employed to calculate the deep geothermal field,considering the constraints of rock thermal properties and terrestrial heat flow in the study area.Furthermore,the“stripping method”is used to determine the contribution rate of sedimentary layer to terrestrial heat flow,while the volume method is applied to estimate the geothermal resources at burial depths of 3000-5000 m.The results show that(1)The heat generation rate of granite is the highest with an average value of 4.52 mW/m^(3),followed by gneiss with an average value in the range of 2.0-3.5 W/(m·K),mudstone and sandstone being the lowest with an average value between 1.0 and 2.0 W/(m·K).(2)The main contributor of terrestrial heat flow in the study area is mantle heat flow,and the contribution of sedimentary layers to terrestrial heat flow only accounts for about 2%.(3)The geothermal resources in Yingjiang Basin within the depth range of 3000-5000 m is 93.6×10^(15)kJ,or 3.2×10^(9)tonnes standard coal equivalent(SCE).

基于熵产理论的多级液力透平能量耗散机理分析

液力透平作为一种液体余压能回收装置,在小水电建设和能量回收领域得到广泛应用,但其内部能量损失特性不清。以两级径流式液力透平为研究对象,基于熵产理论和Omega涡识别准则分析了各过流部件内能量耗散机理。结果表明:速度脉动和壁面效应是能量损失的主要来源,设计工况下二者总占比为98.03%。叶轮和导叶是透平内能量耗散的主要区域;小流量工况,叶轮损失占比较高;大流量工况下,导叶损失占比较高。叶轮内的能量损失源于叶片前缘分离涡、吸力面回流涡以及叶片尾缘涡等不稳定流动现象,而相对液流角与叶片进口安放角的不匹配是导致叶轮内产生不稳定流动的根本原因;在导叶和导叶Ⅱ-反导叶中,不同流量下导致其能量耗散的因素基本保持一致,叶片前缘失速涡和流动分离等劣态流动引起的动量交换是导致能量损失的主要原因。环形吸水室内流动的非对称性导致导叶Ⅰ各流道内熵产率分布不均匀,而导叶Ⅱ-反导叶通过正导叶的整流减小了冲击效应,各流道内熵产率分布均匀且高熵区较小。

On the fundamental equation of nonequilibrium statistical physics—Nonequilibrium entropy evolution equation and the formula for entropy production rate

In this paper the author presents an overview on his own research works. More than ten years ago, we proposed a new fundamental equation of nonequilibrium statistical physics in place of the present Liouville equation. That is the stochastic velocity type’s Langevin equation in 6N dimensional phase space or its equivalent Liouville diffusion equation. This equation is time-reversed asymmetrical. It shows that the form of motion of particles in statistical thermodynamic systems has the drift-diffusion duality, and the law of motion of statistical thermodynamics is expressed by a superposition of both the law of dynamics and the stochastic velocity and possesses both determinism and probability. Hence it is different from the law of motion of particles in dynamical systems. The stochastic diffusion motion of the particles is the microscopic origin of macroscopic irreversibility. Starting from this fundamental equation the BBGKY diffusion equation hierarchy, the Boltzmann collision diffusion equation, the hydrodynamic equations such as the mass drift-diffusion equation, the Navier-Stokes equation and the thermal conductivity equation have been derived and presented here. What is more important, we first constructed a nonlinear evolution equation of nonequilibrium entropy density in 6N, 6 and 3 dimensional phase space, predicted the existence of entropy diffusion. This entropy evolution equation plays a leading role in nonequilibrium entropy theory, it reveals that the time rate of change of nonequilibrium entropy density originates together from its drift, diffusion and production in space. From this evolution equation, we presented a formula for entropy production rate (i.e. the law of entropy increase) in 6N and 6 dimensional phase space, proved that internal attractive force in nonequilibrium system can result in entropy decrease while internal repulsive force leads to another entropy increase, and derived a common expression for this entropy decrease rate or another entropy increase rate, obtained a theoretical expression for unifying thermodynamic degradation and self-organizing evolution, and revealed that the entropy diffusion mechanism caused the system to approach to equilibrium. As application, we used these entropy formulas in calculating and discussing some actual physical topics in the nonequilibrium and stationary states. All these derivations and results are unified and rigorous from the new fundamental equation without adding any extra new assumption.

江西芦溪县南部大地热流特征

江西省芦溪县南部地区地热资源丰富,但地热地质研究程度较低,大地热流测量工作进行的较少,制约着区域地热资源勘查开发。本文以芦溪县南部的新泉和石溪为研究区,结合钻孔岩心热物性测试和地温测井等分析了研究区岩石热导率、地温场、热源机制的特征。研究区岩石热导率平均值为2.063~6.176W/(m·K),热导率最高的为硅质石英岩,可作为良好的导热岩体。大地热流平均值为76.39 mW/m^(2),远高于中国内地地区的平均值62.5 mW/m^(2),该地区具有较高的热背景值。花岗岩放射性生热率平均值为2.16μW/m^(3),不属于高产热型岩体,放射性生热对地表热流贡献较小,热源来源为地壳深部供热。研究区构造活动强烈,深大断裂和次级断裂发育,为地下热水的深部循环提供了良好的导热和导水通道。本研究可为武功山地区的地热资源开发提供重要启示。

液环式航空燃油离心泵自吸性能

基于Mixture模型对液环式航空燃油泵进行自吸阶段的非稳态数值计算,研究自吸过程中燃油泵内气液两相分布的变化过程,对不同时刻下燃油泵内部含气率、气液两相分布、压力及速度流线、熵产率和湍动能变化规律进行分析.结果表明:燃油泵的吸气和排气主要集中在自吸过程的前期和中期;随着自吸时间的增加,各监测面的含气率逐渐降低,当自吸时间为3.00 s时,蜗壳出口含气率接近于0,自吸过程结束;泵内压力随相对距离的增加而增大,泵内同一相对距离平面压力随自吸时间的增加而增大;在气液混合时,高速区域主要集中在叶轮中间流道和蜗壳壁面处,低速区域则集中分布在隔舌附近和导叶出口;随着自吸过程的进行,泵内湍动能和熵产率也随之增大,泵内能量损失增大,主要集中在叶轮叶片、导叶叶片和蜗壳出口处.

基于数据分析的油田加热炉能效影响因素研究

为提高油田加热炉的运行能效,在梳理能效计算方法的基础上,利用节能监测数据分析过剩空气系数、烟气含量、排烟温度、环表温差、负荷率、炉膛压力等对加热炉能效的影响程度,并结合熵权-灰色关联法完成因素的排序,用于评价在用加热炉的用能情况。结果表明,过剩空气系数主要影响排烟热损失,不影响散热损失和气体不完全燃烧损失,与热效率呈负相关;排烟温度与排烟热损失率呈正相关,与热效率呈负相关;环表温差与散热损失率呈正相关,其在热效率较低时对加热炉能效的影响更大;热效率随负荷率的增加先增大后减小,炉膛压力为30~50 kPa是加热炉热效率的高效区间;影响加热炉能效的主控因素从大到小依次为负荷率、排烟温度、过剩空气系数和环表温差。研究结果可为油田节能降耗提供理论依据。

Local Entropy Production in Turbulent Shear Flows:A Tool for Evaluating Heat Transfer Performance

热转移设备的表演评估能在这些设备基于全面的熵生产。在我们的学习，我们因此由于机械精力的驱散并且由于热传导为本地熵生产的系统、详细说明的决心提供方程，两个在狂暴的流动。在当模特儿的骚乱为波动的部分被合并了以后，全面的熵生产能被集成关于整个流动领域决定。然而，从那时起，熵生产率证明很陡峭的坡度关门到墙，数字答案与墙功能是更加有效的熵生产术语。当高级雷纳兹数字骚乱模型被使用时，这些墙功能是强制的。为在有一盘插入的扭曲的磁带的一根管子中的狂暴的流动，作为热转移倡导者，基于全面的熵生产率，从一个热力学的观点的清楚的陈述是可能的，这被显示出。没有，为扭曲力量的某个范围，在与盒子相比的全面的熵生产有减少插入。另外，最佳扭曲力量能是坚定的。当仅仅压力落下和热转移数据被给时，这个信息是无法获得的。关键词熵生产 - 狂暴的热转移 - 墙功能 CLC 数字

Second Law of Thermodynamics Formalism Applied to Finite Duration through Cycles of Living Dissipative Systems

A simple and general theory to describe basic irreversible thermodynamic aspects of aging in all dissipative living is presented. Any dissipative system during its operation continuously loses efficiency by the production of structural or functional defects because of the second law of thermodynamics. This continuous loss of efficiency occurs on all the dissipative systems through the realization of specific functional cycles, leading to a maximum action principle of any system involving the Planck’s constant during their total dissipative operation. We applied our theory to the calculation of men and women lifespans from basal metabolic rate per unit weight and to the calculation of a new aging parameter per cycle of some human organs or physiological functions. All microscopic theory of the aging of living beings should be consistent with the second law of the thermodynamics. In other words, the operation of the biological self-organized structures only implies a delay in which the dissipative biological systems outside of equilibrium approach inexorably to the thermodynamic equilibrium obeying the second law of the thermodynamics.

The intrinsic depth of horizontal convection

The mainstream depth of a return flow can be viewed as an intrinsic depth of horizontal convection. By using a theoretical tube model combined with the application of the Maximum Entropy Production Principle (MaxEPP) in thermodynamics, the following statements can be made. Under fixed external forcing, the system chooses a particular depth as the mainstream depth of its return flow, the depth of which not only satisfies the maximum circulation rate and the maximum heat transport, but also satisfies the maximum entropy production rate. A comparison between this intrinsic depth and the container height leads to the definition of a relative partial and full-penetration pattern of the circulation. Moreover, this intrinsic depth is found to vary with the external forcing; the regulation of this variation is related to the Modified Rayleigh number.

Study on the Irreversible Thermodynamics of a Marine Engine Exhaust-powered Adsorption Refrigerating System

这研究调查热和一台海洋的引擎的质量传递机制由使用不可逆的热力学的用尽动力的吸附使冷系统。熵生产率的 Theequations 和热力学的流动和力量的线性现象学的方程被建立。统一试管的常规试验性的设备被开发，现象学的系数被适合试验性的数据获得。在吸附物床上的热力学的过程被热和质量传递的联合效果决定，这被结束；而且，质量传递被热传递决定。增加热传递的 Takingsome 措施能改进使冷的吸附的表演系统。在这篇论文介绍的结论可能具有到系统的设计应用程序的价值。

The Stability Criterion Model and Stability Analysis of Waxy Crude Oil Pipeline Transportation System Based on Excess Entropy Production

Based on the theory of non-equilibrium thermodynamics, considering the dynamic effect of molecular diffusion and the change in thermodynamic parameters caused by wax precipitation, the phenomenological relations of different thermodynamic "force" and "flow" interactions were derived. The corresponding thermodynamic model of a waxy crude oil pipeline transportation system was built, and then, the excess entropy production expression was proposed. Furthermore, the stability criterion model of the pipeline transportation system was established on the basis of Lyapounov stability theory. Taking the oil pipeline in Daqing oilfield as an example, based on the four parameters of out-station temperature, out-station pressure, flow rate and water content, the stable and unstable regions of the system were divided, and the formation mechanisms of the two different regions were analyzed. The experimental loop device of wax deposition rate was designed, and then, the wax deposition rate under the four parameters was measured. The results showed that the stable region of the wax deposition rate fluctuation was basically in accordance with the stability region analyzed by the criterion model established in this paper, which proved that the stability criterion model was feasible for analyzing the stability of the waxy crude oil pipeline transportation process.

Motoyosi Sugita—A “Widely Unknown” Japanese Thermodynamicist Who Explored the 4th Law of Thermodynamics for Creation of the Theory of Life

The purpose of this paper is to introduce to you, the Western people, nowadays a “widely unknown” Japanese thermodynamicist by the name of Motoyosi Sugita and his study on the thermodynamics of transient phenomena and his theory of life. This is because although he was one of the top theoretical physicists in Japan before, during and after WWII and after WWII he promoted the establishment of the biophysical society of Japan as one of the founding members, he himself and his studies themselves have seemed to be totally forgotten nowadays in spite that his study was absolutely important for the study of life. Therefore, in this paper I would like to present what kind of person he was and what he studied in physics as a review on the physics work of Motoyosi Sugita for the first time. I will follow his past studies to introduce his ideas in theoretical physics as well as in biophysics as follows: He proposed the bright ideas such as the quasi-static change in the broad sense, the virtual heat, and the field of chemical potential etc. in order to establish his own theory of thermodynamics of transient phenomena, as the generalization of the Onsager-Prigogine’s theory of the irreversible processes. By the concept of the field of chemical potential that acquired the nonlinear transport, he was seemingly successful to exceed and go beyond the scope of Onsager and Prigogine. Once he established his thermodynamics, he explored the existence of the 4th law of thermodynamics for the foundation of theory of life. He applied it to broad categories of transient phenomena including life and life being such as the theory of metabolism. He regarded the 4th law of thermodynamics as the maximum principle in transient phenomena. He tried to prove it all life long. Since I have recently found that his maximum principle can be included in more general maximum principle, which was known as the Pontryagin’s maximum principle in the theory of optimal control, I would like to explain such theories produced by Motoyosi Sugita as detailed as possible. And also I have put short history of Motoyosi Sugita’s personal life in order for you to know him well. I hope that this article helps you to know this wonderful man and understand what he did in the past, which was totally forgotten in the world and even in Japan.

基于多方法融合的低产低效气井优选

随着致密气田的深入开发,低产低效井逐年增加,已经成为制约气田开发的关键问题之一。以苏里格气田某区块30口气井为研究对象,引入产量贡献率作为动态分类指标,运用气井产量贡献率累计分布曲线的类分割点将气井划分为4类。以纵向合采砂体数、有效砂体厚度、孔隙度、渗透率和含气饱和度等参数作为静态评价指标,采用熵权-理想点法,对气井进行静态分类。基于动态和静态分类结果,引入自相关距离判断异常值点,进行低产低效气井优选。研究表明,Ⅰ、Ⅱ、Ⅲ、Ⅳ类气井的储层质量依次变差,累计产量依次减小;4口气井为低产低效井,优选结果符合生产实际。该研究成果可为气田进一步挖潜的选井、选层提供一种新的技术途径。