拖曳系数,drag coefficient
1)drag coefficient拖曳系数
1.Study on Sea Ice Geometric Parameters and Parameterization of Drag Coefficient Based on Image Analysis;基于图像分析的海冰几何参数和拖曳系数参数化研究
2.In the sea ice dynamics, the wind and current drag forces are the main driving forces during breaking and drifting of sea ice, and determination of the drag coefficients is the core for calculating the drag force.风和流对海冰的拖曳系数是海冰数值模式中的基本参数,它是精确模拟海冰漂移轨迹,分析海冰的动力破坏、海冰爬升与堆积问题的重要依据。
3.In this paper,turbulent flux over canopy of field crops was calculated using Profile Gradient Method derived from Monin Obhov Similarity Theory and drag coefficient,Stanton number and Dalton number were also further defined.根据农田植被层上方的温湿风梯度观测资料,采用基于莫宁-奥布霍夫相似理论的廓线梯度法计算了农田植被层上方的湍流通量,进而确定出拖曳系数、斯坦顿数和道尔顿数。
英文短句/例句

1.The drag coeficient varies with the shape of the object.拖曳系数随物体的形状而异。
2.Influence of wind drag coefficient on wind-drived flow simulation风应力拖曳系数选取对风生流数值模拟的影响
3.The Study of Optimization of Drag Coefficient in the Simulation of Storm Surges风暴潮模型中风应力拖曳系数的优化研究
4.Deducing the wind stress drag coefficient and the oceanic eddy viscosity profile by data assimilation数据同化反演风应力拖曳系数以及垂向涡动黏性系数的分布
5.Study on Sea Ice Geometric Parameters and Parameterization of Drag Coefficient Based on Image Analysis;基于图像分析的海冰几何参数和拖曳系数参数化研究
6.Sensitivity experiments of the response of tropical Pacific to the wind stress in an Oceanic General Circulation Model热带太平洋对风应力拖曳系数响应的敏感性试验
7.In many cases an overall drag coefficient is given so that the net force on the surface can be determined.在许多情况下,总的拖曳系数是已知的,因而可以确定作用于表面上的净力值。
8.Control for the Profile Motion of a Towed System and Data Processing;拖曳式测量系统剖面运动控制与数据产品制作
9.General Design, Evaluation and Application of of Towed Multi-parameter Profling System;拖曳式多参数剖面测量系统的总体设计、功能评价及应用
10.A charge for towing.拖曳费拖曳所付的费用
11.towed underwater TV-camera system拖曳式水下电视摄像系统
12.Study on Near-Surface Towed TEM Receiver System浅层地面拖曳式TEM接收系统研究
13.Underwater Stereo-PIV System in Towing Tank拖曳水池水下三维PIV测试系统研究
14.Towing body of towing profiler and its experiment拖曳式剖面探测拖体系统构成及运动控制试验
15.The model is a6.0 m model of CB=0.60, Series60, and the test was conducted in the towing tank of China Ship ScientificResearch Center( CSSRC).试验在中国船舶科学研究中心(SSRC)拖曳水池进行,模型长6.米,方形系数0.0。
16.Drag Field Buttons to the following areas to layout your PivotTable请将字段按钮拖曳到数据透视表上适当的位置。
17.Numerical Modeling of a Down-pulling Lithospheric Root Beneath the Collision Mountain Ranges in the Tibetan Plateau;青藏造山带岩石圈根拖曳模式的数值模拟
18.Predicting the position and analyzing the parameters of a towed array during the maneuvering of a submarine潜艇机动时拖曳线列阵阵位预报与参数分析
相关短句/例句

wind drag stress coefficient风拖曳力系数
1.Research of the effluence of tidal level on wind drag stress coefficient in storm surge model;风暴潮模拟中潮位对风拖曳力系数的影响研究
3)wind drag coefficient风应力拖曳系数
1.Influence of wind drag coefficient on wind-drived flow simulation风应力拖曳系数选取对风生流数值模拟的影响
4)dragging parameter拖曳参数
5)towing data拖曳数据
6)towing system拖曳系统
1.A towing system for ocean profiling multiparameter measurement;用于海洋多参数剖面测量的拖曳系统
2.The influences of towline on dynamic stability of vehicles were calculated and analyzed by using the simplified longitudinal small disturbance equation of towing system.采用简化的拖曳系统纵向小扰动运动方程,计算分析了拖缆对拖曳系统中飞行器纵向扰动运动模态的影响。
延伸阅读

阀门技术注重流量系数和气蚀系数阀门的流量系数和气蚀系数是阀的重要参数,这在先进工业国家生产的阀门资料中一般均能提供。我国生产的阀门基本上没有这方面资料,因为取得这方面的资料需要做实验才能提出,这是我国和世界先进水平的阀门差距的重要表现之一。3.1、阀门的流量系数
阀门的流量系数是衡量阀门流通能力的指标,流量系数值越大,说明流体流过阀门时的压力损失越小。
按KV值计算式
式中:KV—流量系数
Q—体积流量m3/h
ΔP—阀门的压力损失bar
P—流体密度kg/m3
3.2、阀门的气蚀系数
用气蚀系数δ值,来选定用作控制流量时,选择什么样的阀门结构型式。
式中:H1—阀后(出口)压
H2—大气压与其温度相对应的饱和蒸气压力之差m
ΔP—阀门前后的压差m
各种阀门由于构造不同,因此,允许的气蚀系数δ也不同。如图所示。如计算的气蚀系数大于容许气蚀系数,则说明可用,不会发生气蚀。如蝶阀容许气蚀系数为2.5,则:
如δ>2.5,则不会发生气蚀。
当2.5>δ>1.5时,会发生轻微气蚀。
δ<1.5时,产生振动。
δ<0.5的情况继续使用时,则会损伤阀门和下游配管。
阀门的基本特性曲线和操作特性曲线,对阀门在什么时候发生气蚀是看不出来的,更指不出来在那个点上达到操作极限。通过上述计算则一目了然。所以产生气蚀,是因为液体加速流动过程中通过一段渐缩断面时,部分液体气化,产生的气泡随后在阀后开阔断面炸裂,其表现有三:
(1)发生噪声
(2)振动(严重时可造成基础和相关构筑物的破坏,产生疲劳断裂)
(3)对材料的破坏(对阀体和管道产生侵蚀)
再从上述计算中,不难看出产生气蚀和阀后压强H1有极大关系,加大H1显然会使情况改变,改善方法:
a.把阀门安装在管道较低点。
b.在阀门后管道上装孔板增加阻力。
c.阀门出口开放,直接蓄水池,使气泡炸裂的空间增大,气蚀减小。
综合上述四个方面的分析、探讨,归纳起来对闸阀、蝶阀主要特点和参数列表便于选用。两个重要参数在阀门运用中 。