期刊文献+
共找到3篇文章
< 1 >
每页显示 20 50 100
贵州雨凇积冰过程的云层特征及环流背景 被引量:10
1
作者 赵彩 《气象》 CSCD 北大核心 1995年第5期48-52,共5页
雨凇形成的基本条件是地面温度在0℃以下并有过冷雨滴降至地面,严重雨凇过程的特点即是上述条件维持时间长而且有较大的过冷雨滴降水。作者使用贵阳56次探空和高空风资料,着重分析了贵州中部严重积冰过程的云内宏观热力、动力特征... 雨凇形成的基本条件是地面温度在0℃以下并有过冷雨滴降至地面,严重雨凇过程的特点即是上述条件维持时间长而且有较大的过冷雨滴降水。作者使用贵阳56次探空和高空风资料,着重分析了贵州中部严重积冰过程的云内宏观热力、动力特征,发现云层厚度、云上部0℃以上暖层的存在以及云层中上部湍流强度等因子对过冷雨滴降水量有重大影响。同时,还分析了形成这种云层宏观特征的天气系统及大尺度环流背景。 展开更多
关键词 雨凇 云层 动力不稳定性 环流背景 积冰过程
下载PDF
Degradation of Soils in the Lowland of Kur-Araz
2
作者 E. A. Gurbanov S. A. Ganiyeva 《Journal of Agricultural Science and Technology(A)》 2011年第2X期249-254,共6页
The research works were carried out for determination of the washout, types, sorts and level of the development reasons of degradation with the purpose of preparation of the measures of fight against degradation in th... The research works were carried out for determination of the washout, types, sorts and level of the development reasons of degradation with the purpose of preparation of the measures of fight against degradation in the soils in 2005-2009 in the lowland of Kur-Araz. The investigations were fulfilled by using of geographical and stasionar methods. It is revealed that 333.6 thous, ha of the soils of the lowland of Kur-Araz have been exposed to erosion. 97.4 thousand ha of them have been exposed to rainstorm erosion, 127.1 thous, have been exposed to irrigative and 122.1 thous, ha to wind erosion. The most dangerous of them are considered irrigative erosion. Under the influence of erosion process in deposited over the length of furrow, deposits the changes happened in maintenance of humus and nutritions elements. In dependence on slope and water expenditure on 1 ha 2.23-14.86 t of soil are leached. As a result of out wash from 1 ha of soil 55.88-304.59 kg of humus, 4.06-20.80 kg of nitrogen, 4.57-26.55 of phosphorus and 57.40-372.99 of potassium are lost. The soil is exposed to degradation and as a result a process of desertification begins. On the basis of the quantitative an intensity of soil outwash the possible losses of dry matter including humus and main elements of nutrition of plants as a result of erosion, their deposit with the water way, are calculated, too. 展开更多
关键词 Irrigative erosion erosion degradation wind erosion defination capacity removal of humus.
下载PDF
发动机整流支板及帽罩积冰的数值模拟 被引量:2
3
作者 梁久立 宣益民 连文磊 《工程热物理学报》 EI CAS CSCD 北大核心 2020年第8期1991-1996,共6页
航空发动机在高空结冰气象条件下工作时,其进口部件,如进气道、整流支板、帽罩以及压气机前几级叶片会因为冷空气中液态水滴的撞击和聚集而在表面产生积冰,严重影响发动机的工作性能和飞行安全。采用数值模拟方法,对整流支板和帽罩在相... 航空发动机在高空结冰气象条件下工作时,其进口部件,如进气道、整流支板、帽罩以及压气机前几级叶片会因为冷空气中液态水滴的撞击和聚集而在表面产生积冰,严重影响发动机的工作性能和飞行安全。采用数值模拟方法,对整流支板和帽罩在相应工作状态下的积冰过程进行了三维数值计算。较小尺寸水滴会增大部件表面的水滴收集区和积冰覆盖区,而大尺寸水滴与固壁面的相互作用带来子水滴的返流和再附着,造成局部表面水滴收集率下降.模拟得到不同因素在相应条件下对部件表面的积冰覆盖范围和厚度分布影响,为发动机防/除冰系统的设计提供理论指导。 展开更多
关键词 过冷水滴 数值模拟 积冰过程 水滴收集
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部