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水泵水轮机S特性区能量损失及流动特性研究
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作者 王李科 姚亮 +3 位作者 冯建军 朱国俊 卢金玲 阮辉 《水利学报》 EI CSCD 北大核心 2024年第3期344-354,366,共12页
为了调节电网的稳定性,抽水蓄能电站需要频繁启停和变换工况运行,导致水泵水轮机容易进入S特性区,机组振动增加,并网失败。本文以模型水泵水轮机为研究对象,采用熵产理论详细分析了S特性区不同工况下的能量损失规律,明确了熵产率分布与... 为了调节电网的稳定性,抽水蓄能电站需要频繁启停和变换工况运行,导致水泵水轮机容易进入S特性区,机组振动增加,并网失败。本文以模型水泵水轮机为研究对象,采用熵产理论详细分析了S特性区不同工况下的能量损失规律,明确了熵产率分布与内部流动结构的关系。结果表明:S特性区内近飞逸工况总熵产最大,约为设计工况的5.1倍,脉动熵产占据的比例接近80%,随着流量的减小,转轮熵产占比逐渐降低,活动导叶和尾水管的熵产占比增加。小流量工况转轮进口靠近下环位置首先出现了明显的漩涡,导致了活动导叶出口和转轮进口的高熵产区,随着流量进一步减小,漩涡逐渐向上冠转移,并且切向速度增大,在转轮进口形成挡水环,阻碍水流进入转轮,在无叶区内出现了环状分布的高熵产区。反水泵工况,水流在低压边与逆时针旋转的叶片撞击,导致水流很难进入叶片内部,形成了大尺度的回流涡结构;双列叶栅内充满大量涡结构,导致活动导叶吸力面的熵产率增大,并且向固定导叶传播。 展开更多
关键词 水泵水轮机 s特性 熵产理论 回流涡
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Introduction to Thermo-Photo-Electronics
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作者 Stanislav Ordin 《Journal of Electronic & Information Systems》 2023年第1期51-66,共16页
Building the foundations of Thermo-Photo-Electronics became possible only after the correction of thermodynamic errors in the traditional theory of semiconductor Electronics and Photo-Electronics.It is these errors th... Building the foundations of Thermo-Photo-Electronics became possible only after the correction of thermodynamic errors in the traditional theory of semiconductor Electronics and Photo-Electronics.It is these errors that determined the output of the asymptotics of the operating parameters of semiconductor electronic devices,in particular,both the saturation of the limiting clock frequency of processors,and the saturation of the efficiency of both thermoelectric and photoelectric converters.But in semiconductors,although these thermodynamic errors manifested themselves not only in the instrumental,but also in the technological aspect,they could not prohibit semiconductor Electronics itself,unlike Electronics based on other materials.It’s just that a number of qualitative mistakes were made in the theory of semiconductor devices and photo devices.In this work,it is shown that the energy band diagram of semiconductor contacts itself was constructed with a significant omission-without taking into account the temperature force on the contact.At the same time,because of the incorrect calculation of currents according to the outdated formulas of Richardson-Langmuir-Deshman,there were also PROHIBITIONS.So the practitioners compensated for the errors of the theory with“empirical corrections”.So electronics engineers often made devices not according to a strict theory(which simply did not exist until now),but on a hunch and according to empirical local laws.And only the correction of the historical mistakes made it possible to expand the phenomenology of the description of processes in a Solid Body,on the basis of which it is possible to make calculations of highly efficient elements of Photo-Thermo-Electronics. 展开更多
关键词 PHENOMENOLOGY Potential barriers P-n-junction prigogine local entropy production Richardson-Langmuir models Local thermo-EMF
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Motoyosi Sugita—A “Widely Unknown” Japanese Thermodynamicist Who Explored the 4th Law of Thermodynamics for Creation of the Theory of Life
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作者 Kazumoto Iguchi 《Open Journal of Biophysics》 2016年第4期125-232,共109页
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 a... 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. 展开更多
关键词 Unknown Japanese Thermodynamicist Motoyosi sugita Thermodynamics of Transient Phenomena Virtual Heat Broad Quasi-static Change Chemical Potential Field of Chemical Potential Diffusion Phenomena Number of Partition Dissipation Function Onsager’s Theory of Irreversible Processes prigogine’s Least production of entropy 4th Law of Thermodynamics Maximum Principle Pontryagin’s Maximum Principle Bellman’s Optimality Principle Theory of Metabolism Theory of Life CYBERNETICs
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On the fundamental equation of nonequilibrium statistical physics—Nonequilibrium entropy evolution equation and the formula for entropy production rate 被引量:2
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作者 XING XiuSan Department of Physics, Beijing Institute of Technology, Beijing 100081, China 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2010年第12期2194-2215,共22页
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... 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. 展开更多
关键词 stochastic velocity type’s Langevin EQUATION in 6N dimensional phase space DRIFT-DIFFUsION duality NONEQUILIBRIUM entropy evolution EQUATION entropy diffusion FORMULA for entropy production rate entropy change from internal interaction a
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论非平衡态热力学稳定性的超熵产生判据
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作者 吴传生 《武汉工学院学报》 1991年第3期63-69,共7页
本文运用同线性化稳定性原理比较的方法,分析了非平衡态热力学稳定性超熵产生判据的适用性。
关键词 非平衡态 热力学 稳定性 超熵
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社会系统非平衡定态特性之系统方法研讨方略 被引量:5
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作者 聂云 《系统工程理论与实践》 EI CSCD 北大核心 1999年第10期20-26,共7页
运用系统方法理论研究社会系统取决于模型系统选取的合理程度. 由动力学变量决定的社会态函数所提供的信息可以定义Shannon 社会熵. 定态社会系统的产生熵可以描述社会系统的不可逆过程并且是一个很好的Ляпунов函数,... 运用系统方法理论研究社会系统取决于模型系统选取的合理程度. 由动力学变量决定的社会态函数所提供的信息可以定义Shannon 社会熵. 定态社会系统的产生熵可以描述社会系统的不可逆过程并且是一个很好的Ляпунов函数,它使我们对定态自组织的社会系统的整体稳定性充满自信.社会系统的Fokker-Planck 方程及其定态解的时间发展行为可以解释社会系统的非平衡相变. 尤以知识结构的创新对社会系统的发展壮大以致于出现非平衡相变都起着决定性的作用. 展开更多
关键词 社会系统 大系统 系统方法 非平衡相变
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