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91.
92.
Load dynamic matching of supply and demand side based on the utilization of urban sewage heat energy
Flowing dynamic characteristics and its temperature dynamic characteristics of a three-level sewage pipe network in Chongqing were analyzed. A mall's building whole year load was simulated. In the adverse condition of wastewater flow, the market construction peak discharge heat was compared with the sewage heat load, the balance between the most adverse flow and the building demand was found. Explored supply and demand matching method between urban sewage and city building load in flow adverse condition to take full advantage of the urban sewage cold and hot resources. the composite system was adeptcd to make up the most unfavorable flow time of sewage average heat load and the construction load difference; it also puts forward principle of load sharing and control strategy aimed at compound system. 相似文献
93.
The p order balance and interpolatory property is introduced to M band multiwavelets. Balance conditions for M band multiwavelets are investigated in time domain and frequency domain respectively. The balanced order is equal to its approximation order for M band interpolatory multiwavelet. 相似文献
94.
95.
Condition assessment on power transformer is an important approach to improve reliability of transformer and provide proper decision-making for condition-based maintenance. For long, static assessment method used in the past has already not adapted to the development of modem electricity transmission and distribution technology. So based on the deficiency of fuzzy synthetic assessment method, matter-element synthetic assessment method is introduced. The method can evaluate transformer condition not only in quality but also in quantity. Because each index weight can be given fairly and fast through improved analytic hierarchy process, which need not carry on consistency chec accuracy of assessment can be improved. Examples analysis has proved that assessment method of power transformer condition based on matter-element theory is rational and effective. 相似文献
96.
In this paper, partial differential equations of vortex flow-stream function in boundary fitted coordinates and related ADI equations were listed. The flow around a cylinder in quadrilateral area by auto control boundary was computed. The diagram of distribution of speed arrow, constant lines of flow-stream function, vortex, two speed parts and pressure were studied. 相似文献
97.
In this paper, according to the study on a great number of experiments and data analyses, the sedimentation rule of solid particles in debris flow is set up. Three main factors that influence the particle sedimentation in debris flow were studied; the basic reasons to influence the particle sedimentation were analyzed. The particle sedimentation in debris flow could be divided into three stages,i, e. the starting stage, the quick sedimentation stage and the accumulation stage,and detailed analysis on the sedimentation process each stage was made. The liquid viscosity, particle quality and additional water pressure have an important role on the sedimentation rule of the particle in debris flow. 相似文献
98.
99.
A continuity condition of p-forms across a p-dimensional submanifold isderived.The,various interface conditions of electromagnetic quantities are obtained through theapplication of the continuity condition to Minkowski manifold of space-time. 相似文献
100.
切线泵流动特征的整流场数值模拟 总被引:5,自引:0,他引:5
对单级切线泵在设计工况进行了定常流动数值模拟,分析了叶轮流道及蜗壳内的液体流动情况。结果表明,切线泵内流场非常复杂,叶轮进口有明显冲击,叶轮各流道的速度、压力差异很大,环形蜗壳内流动呈现旋涡推进特征,上、下游流动有强烈的相互作用,整机流场不具有对称性;环形蜗壳的几何结构以及流场上、下游的相互作用是导致整机流场非对称特性的主要原因。计算结果为进一步改进结构、提高性能、减小水力损失提供了理论依据。 相似文献