推荐回答(5个)
风向标的箭头指向西时,当时刮的是西风。
解释:在风力的作用下,风向标绕铅直轴旋转,使风尾摆向下风方向,头部指向风的来向。所以题目中是“风向标的箭头指向东”,而头部指向风的来向,所以“风向标的箭头指向东时,当时刮的是西风”。
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基本原理:
当风的来向与风向标成某一交角时,风对风向标产生压力,这个力可以分解成平行和垂直于风向标的两个风力。由于风向标头部受风面积比较小,尾翼受风面积比较大,因而感受的风压不相等,垂直于尾翼的风压产生风压力矩,使风向标绕垂直轴旋转,直至风向标头部正好对风的来向时,由于翼板两边受力平衡,风向标就稳定在某一方位。
风向标的箭头永远指向风的来源,其原理其实非常简单:箭尾受风面积比箭头大,若箭头及箭尾均受风,箭尾必会被风推后,使箭头移往风的来源。
西风。风向,是指风吹来的方向。 风向标是用于测定风来向的仪器,风向标是一个不对称形状的物体,重心点固定于垂直轴上。当风吹过,对空气流动产生较大阻力的一端便会顺风转动,显示风向。
金属风向标由风标、风轮、尾翼、动杆、主杆、底座等六部分组成。主体部分为优质不锈钢材料;风叶采用优质工程塑料制作,耐腐蚀性强;动杆部分采用优质双不锈钢防水轴承,灵敏度高,启动风速小,经久耐用。
风向标具有安装简易、运输便捷的特点,广泛应用于气象化工、矿区开采、农业生产、油田勘探、风力发电等行业。
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一、设计要求
1、 在风小时能反应风向的变动,即有良好的启动性能;
2、具有良好的动态特性,即能迅速准确地跟踪外界的风向变化。
二、动态特性
对于风向标,当风向变化时,它将经过一个阻尼简谐振动产生过量指示而逐渐趋于稳定。
风向标的响应取决于环境量、仪器的响应速度和加速度。
三、信号转换
风向标感应的风向必须传递到地面的指示仪表上,以电触点式最为简单。风向标带动触点,接通代表风向的灯泡或记录笔电磁铁,作出风向的指示或记录,但一般只能作到每一个方位有一个触点。
西风。风向,是指风吹来的方向。
风向标是用于测定风来向的仪器,风向标是一个不对称形状的物体,重心点固定于垂直轴上。当风吹过,对空气流动产生较大阻力的一端便会顺风转动,显示风向。
风向标外观可划分尾翼、平衡锤、偏向杆、转动轴四部位。流速和风向是各是运用磁感流速杯和风向标来度量。磁感流速杯大多数有三个对应风杯,稳固於垂直轴上,令各个风杯的直径面都有垂直。
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扩展资料
作用原理
当风的来向与风向标成某一交角时,风对风向标产生压力,这个力可以分解成平行和垂直于风向标的两个风力。由于风向标头部受风面积比较小,尾翼受风面积比较大,因而感受的风压不相等,垂直于尾翼的风压产生风压力矩,使风向标绕垂直轴旋转,直至风向标头部正好对风的来向时,由于翼板两边受力平衡,风向标就稳定在某一方位。
风向标的箭头永远指向风的来源,其原理其实非常简单:箭尾受风面积比箭头大,若箭头及箭尾均受风,箭尾必会被风推后,使箭头移往风的来源。
风向是指风吹来的方向,如果风向标指北,那风就是从南面吹来的(上北下南),是南风
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