分布参数
- 与 分布参数 相关的网络例句 [注:此内容来源于网络,仅供参考]
-
A generalized mathematical model was developed to describe the distribution of over-potential.Dimensionless variables μ and ω that characterize the polarization and influence of side electrode reaction in the system,were derived from modeling.Adomian's decomposition methodADM)was used to solve the nonlinear differential equation of the model to obtain an approximate analytical solution,which was in the form of algebraic expressions of infinite power series.By the solution,the relationship between over-potential distribution and average selectivity could be easily calculated without solving the nonlinear model time and again.
建立了描述超电势分布的普遍化数学模型,归纳出表征电极极化和副反应影响的量纲1数μ和ω,并用ADM(Adomian's decomposition method)对该非线性微分方程模型求解;所获得的逼近解代数表达式,可方便地计算不同参数下超电势分布对平均选择性的影响,而毋需反复求解模型微分方程。
-
The model selection and parameters optimization for analog channel were discussed. The Laplace model and the Gauss model in common used in the video frequency were researched.
讨论了模拟信道的模型选取和参数优化,研究了视频序列中常用的Laplace模型和Gauss模型,提出了一种带校正系数的虚拟相关信道参数估计方法,验证了虚拟相关信道更接近残差数据的真实分布。
-
The effect of the inlet parameters of air, air mass flow rate and spray water rate on the performance of closed cooling tower is discussed in the paper. A mathematical model for evaluating heat and mass transfer performance of closed cooling tower is set up. The analytical solution of differential equations is derived.
目的 分析闭式冷却塔内各参数,即空气焓值、含湿量、冷却水温等的分布情况;探讨空气入口参数、空气质量流量、喷淋水量对闭式冷却塔冷却性能的影响规律。
-
For general engineering problems, the analytical transformation rules are sufficiently accurate to design the similar cascade profile, but further improvement of the precision is limited by the one-dimensional assumption of the transformation, therefore an inverse blade design method—influence matrix method, based upon the surface vorticity model, is developed to improve the precision effectively.
进一步讨论了在具有相同表面压力系数分布的情形下,进口马赫数对附面层发展的影响,发现在一定条件下,只要表面压力系数的分布相似,则叶面附面层发展情况及无量纲气动力参数也将存在相同精度的相似,这一结论使我们在进行相似流场模拟的模型设计中,得以只进行无粘流场之间的相似变换,从而大大减少相似模型设计的工作量和复杂性。
-
The main work and the originality points of this dissertation could be concluded as the following parts:(1) To analyze systematically the mathematical model of LES of air flow in great space, under the case of isothermal and non-isothermal, as well as the combined action of buoyancy and strain. Some basic problems are studied about the LES application into airflow simulation of great space, such as boundary conditions, spatial difference scheme and time advancing scheme, time step etc., which creates the basis for the LES application to indoor airflow simulation.(2) Both the instantaneous and time averaged flow field of great space with multiple jets under isothermal and non-isothermal cases are explored with large eddy simulation method, and also discussed the dynamic characteristics and the law of fluidflow in the great space.(3) Based on the results of LES of the great space and the Fanger thermal comfort indexes, it is brought forward the concept of the series of dynamic thermal comfort evaluating indexes, which could be divided into thermal comfort index with time averaged properties PD, PPD, PMV, thermal comfort index with instantaneous properties IPD, IPPD, IPMV, and time averaged thermal comfort indexes TAPD, TAPPD, TAPMV, and transient situations time averaged thermal comfort indexes TTAPD, TTAPPD, TTAPMV. The differences among them and the calculation methods are discussed, and the four kinds of indexes are calculated with the thermal comfort index PD as an example.(4) Based on the LES results it is discussed the hot air stratification phenomena in air-conditioned buildings in the case with air supply and return registers on the ceiling and the case on the sidewall. The fundamentals of the hot air stratification are studied and the relations of estimating hot air stratification are brought forward.(5) With the advanced apparatus such as hot wire film anemometer IFA300 and laser particle field anemoscope, corresponding model test and site measurements have been done, which are compared with the simulation results and LES is proved a very promising method in air flow simulation indoor.
本文主要工作既创新点体现在以下几个方面:(1)系统分析了等温、非等温和考虑剪切力与浮升力综合作用的高大空间大涡模拟数学模型,并研究了高大空间大涡模拟在室内气流仿真应用中的一些基本问题,如边界条件、空间离散格式和时间推进格式、时间步长选择等问题,为大涡模拟在室内气流计算中的广泛应用打下了基础;(2)首次用大涡模拟方法研究了高雷诺数下高大空间多射流在等温、非等温情况下的瞬时流场和时均流场分布,并探讨了多射流流场的动态特性和流动规律;(3)基于大涡模拟的动态仿真结果和Fanger的热舒适指标,首次系统地提出了动态热舒适评价指标体系的概念:即基于时间平均参数的热舒适指标PD、PPD、PMV;基于瞬时参数的瞬时热指标IPD、IPPD、IPMV;基于时间平均热舒适指标TAPD、TAPPD、TAPMV;以及沿行动迹线的时间平均热舒适指标TTAPD、TTAPPD、TTAPMV,并分析了四类热舒适指标的差异性和计算方法,还以PD值为例对四类指标分别进行了计算;(4)基于数十种工况下空调房间大涡模拟的结果,研究了空调建筑上送上回和侧送侧回两种情况下热分层现象,并探讨了热分层的基本规律,首次提出了避免热分层现象的判断公式;(5)在暖通空调领域,首次使用IFA300热线风速仪、激光粒子速度场仪等先进设备,完成了与大涡模拟相对应的模型试验,并把实测结果与仿真结果进行了对比,说明LES在室内气流仿真方面是一种很有前景的方法。
-
An adaptive grid scheme controlling cell area is used to generated grids in the divergent section of symmetric annular nozzle, and the generated grids are used in the flowfield calculation through the uncoupled way. The elliptic equations are used to generate grids in three dimensional regions of FDN divergent section, the source terms used in the equations employ a mathematical form which is independent of the boundary shape and of the boundary grid point distribution, the free parameters contained in the source terms are determined by the two restraint conditions, the intersection angle of transverse grid lines with boundaries and the local curvature of the transverse grid lines at the boundaries, and the interior grid distribution controlled directly by the grid point distribution assigned on the boundaries is realized, it makes the grid more clustering near the nozzle wall. For the generated grids in the whole computational regions have a good smoothness and orthogonality, the accuracy of calculation in the flowfield is ensured.
对轴对称的环形喷管采用控制网格面积的自适应网格方法对扩散段部分进行了网格生成,并通过非耦合方式应用于喷管的流场计算中;对强制偏流喷管扩散段内的三维区域采用椭圆型方程进行网格生成,方程中的源项采用了与边界形状和边界网格点分布无关的数学形式,源项内的自由参数由横向网格线与边界的交角及横向网格线在边界处的局部曲率两个约束条件来确定,实现了由边界上的网格分布直接控制内部的网格点,使壁面附近具有较密集的网格,并且在整个计算区域内的网格都具有良好的光滑性和正交性,从而保证了流场计算的准确性。
-
With the combination of lighting, cooling and heating under daylighting, the study on the effect of the key characteristic parameters on total energy consumption is provided. The validation of the comparability of daylight distribution for building antetype and model is made through theoretical analysis and simulating calculation in the thesis. Due to the variable sky condition, daylighting factor is used for experimental validation instead of illuminance. The error analysis of several testing methods used in the experiment is conducted, followed by the experimental validation of the effect of WWR, sill and transmittance on daylighting factor distribution.
基于天空状态的多变性,提出用天然采光因数替代照度进行实验验证,对实验中的几种测试方法进行了误差分析,并通过实验验证了窗墙比、窗台高和透光率对天然采光因数分布的影响。4 为了更直观地分析各参数对照明节电的影响,提出了"特征点"、"特征线"和"特征距离"等概念;分析了天然采光下的照明节能状况,综合考虑照明、采暖和空调能耗,计算分析了几个主要特性参数对总能耗的影响。
-
It was found that electrical field strength and potential around the the sample changed less in the fully insulated chamber than in conducting material phytotron, so it is closer the real condition. Based on the design, the first fully insulated large artificial climate chamber in China, in which temperature , humidity, and atmospheric pressure can be regulated, has been built in our laboratory. The paper developed an insulation parameters automatic test system of high voltage capacitive equipment based on LabVIEW. In the chamber, On-line tanδmeasurements of the capacitive transformer bushings were completed. The effects of environmental factors on tanδwere analyzed, and the curves between the tanδand the environment parameters were acquired. Then, a grey relational model to analyze the effects of main environmental factors on tanδwas built, and the grey relational grade between them was gained in this paper.
完成的主要工作和取得的主要研究成果如下:提出了全绝缘型人工气候室设计方案,计算分析了气候室内悬挂绝缘子和套管时的空间电场分布情况,并和金属材质气候室相比较,论证了该方案的优越性,据此方案研制的全绝缘人工气候室可调节温度、湿度和压力等参数,满足了人工气候试验的要求;开发了基于虚拟仪器技术的高压电容型设备绝缘特性自动测试系统,完成了人工气候室内变压器套管tanδ的在线测量试验,以此为基础分析了环境因素对电容型设备tanδ的影响情况,获得了tanδ与环境参数的关系曲线,建立了环境因素对tanδ影响的灰关联分析模型,得到了主要环境参数与电容型设备tanδ的灰关联度。
-
By means of the plating technology and the system designed and made ourselves, we call them as the direct-heat evaporating roll-pulled with vacuum piston and the helix evaporating of straight heat-wire with the negative thermal specific resistance , the align polishing ring films and the separating ones of pure gold have been plated directly at the inner wall of the capillary of Sealed-off CO〓 laser.
简便有效地使器件的输出功率、光束品质、稳定性和使用寿命都得以提高的作用效果;分析了放电驱动催化机理及催化效果与器件参数、工作状态及其中的等离子体过程的对应关系,建立了数学模型,编程数值计算了放电管内正柱区中等离子体参数分布及其与器件工作外参数的关系;利用我们设计开发的直热式真空活塞卷拖和负阻直热丝螺旋蒸镀工艺及制作的系统,在封离型CO〓激光器毛细管玻璃内壁上直接镀制出了单质金的镜面环膜和离散膜,经理论分析和实验检验,指出美国专利4756000号的环金方案将导致器件工作特性的改变和恶化,降低效率;肯定了正柱区边界部分场对建立良好的激光振荡的作用意义,明确提出了①作为高品质器件设计基础的弥散膜催化剂;②高斯管型弦驻波振动定型磨制、检测的新概念及相应的制备加工工艺;实际制出了管子,测定了其基本的工作特性和初期过程。
-
An equal cross-section blade was investigated and a finite element model was built parametrically. Geometrical parameters (such as length, width and thickness), material parameters (such as young's modulus and density) and speed of blade were considered as input random variables while the static frequencies and dynamic frequencies were output random variables. Combining the finite element method, response surface method and Monte Carlo method, the statistical properties and cumulative distribution functions of static frequencies and dynamic frequencies were obtained. Probability sensitivities analysis, which combined the slope of the gradient and the width of the scatter range of the random input variables, was applied to quantitatively evaluate the sensitivities of static frequencies and dynamic frequencies with respect to the random variables. The Scatter plots of structural responses with respect to the random input variables were illustrated how to adjust the values of the static frequencies and dynamic frequencies by changing input random variables.
文中以某试验台用汽轮机等直叶片为研究对象,考虑几何参数、材料参数和转速的随机性,通过有限元参数化建模,将确定性有限元方法、响应面方法和Monte-Carlo模拟法相结合,从而获得了叶片静频、动频的统计特性和累积分布函数;同时考虑随机变量的梯度和离散范围对静、动频的影响,通过概率敏感性分析,定量地判断出叶片静、动频对随机输入变量的敏感性;通过绘制叶片静、动频与输入变量的散点图,定量地分析了如何改变随机变量以调整静、动频率的方法。
- 推荐网络例句
-
According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.
曝气设备的动力效率在叶轮转速为120rpm~150rpm时取得最大值,此时氧利用率和充氧能力也具有较高值。
-
The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.
稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世,形体几无变化。
-
When I was in school, the rabbi explained everythingin the Bible two different ways.
当我上学的时候,老师解释《圣经》用两种不同的方法。