应力波法测试液动冲击器性能参数的微型计算机系统     

李文印  陈树林  邹春贵  蒋荣庆  穆纪泽  周占江 《吉林大学学报(地球科学版)》1988,(1)

本文详细介绍了用应力波法测试液动冲击器性能参数的微机系统。该系统根据国际标准设计,具有方法先进,设备简单,采样速度快及计算准确等特点。使用该系统,可以很方便地测量冲击器的能量、频率、流量等重要指标。它提供了研究和改进液动冲击器的有效方法,进一步研究将会得知不同冲击器破碎岩石所需的能量。该系统首次在地质系统应用。  相似文献   

Hydrologic/hydraulic modelling and flood risk analysis for the West Tiaoxi Catchment, Taihu Lake Region, China     

Peng-zhu Xu  Tong Jiang  Lorenz King 《中国地理科学(英文版)》2000,10(4):309-318

Located in the headwater upstream of the Taihu Lake region, which is a densely populated and economically developed area in China, the West Tiaoxi River catchment is a frequently food-hit area due to its nature and climatic characteristics. During the last several decades, more than ten catastrophic floods happened in this area, causing huge economic losses. Since 1990, due to the increasing property vulnerability to flood hazard, the disasters were even more serious than before, and economic losses increased year by year. Thus, there have great importance to study flood behaviors, flood risks and their consequences. In this paper the hydrologic/hydraulic modelling is presented firstly. It is the method to study the relationship between rainfall and runoff and the flood propagation process. Secondly, the author gives the summary of the current study methods for flood risk assessment. The West Tiaoxi River catchment has a long history of the construction of polders and hydraulic engineering. Most farmlands have been protected against floods. So the combination method has been used to obtain the real risk area. The results have been obtained by using this method, which, the authors think, will be used in disaster preparedness, property insurance etc. Foundation item: Under the auspices of the National Natural Science Foundation of China (No. 49671028) and Deutsche Forschungsgemeinschaft (DFG). Biography: XU Peng-zhu (1965 —), male, a native of Funing County of Jiangsu Province, associate researcher. His research interests include hydrology and water resources, numerical modelling, and application of GIS to hydrology.  相似文献   

水压爆破拆除大型钢筋混凝土气罐     

李致宗  张炳科  周以恒  张书亮 《南方国土资源》2000,13(3):71-73

文章叙述了水压爆破拆除大型钢筋混凝土气罐的药量计算、药包的加工与布置、起爆网路、爆破安全与防护措施以及爆破施工的体会,可供同类工程借鉴与参考.  相似文献   

Short Note: Effective Hydraulic Conductivity and Transmissivity for Heterogeneous Aquifers     

Daniel M. Tartakovsky  Alberto Guadagnini  Laura Guadagnini 《Mathematical Geology》2000,32(6):751-759

Regional scale models of groundwater flow and transport often employ domain discretizations with grid blocks larger than typical scales of field data. For heterogeneous formations, this difference in scales is often handled by using effective (upscaled) parameters. We investigate the problem of upscaling hydraulic conductivity and transmissivity from a small scale of measurement to a larger scale of grid blocks. Transmissivity statistics is expressed in terms of statistics of hydraulic conductivity, and expressions for the effective (upscaled) hydraulic conductivity K _eff and transmissivity T _eff for steady state flow in confined heterogeneous aquifers are derived by means of stochastic averaging and perturbation analysis. These expressions reveal that the commonly used relation T _eff = BK _eff, where B is the confined aquifer thickness, is not generally valid.  相似文献   

交流变频钻机能实现升降钻具机械化          下载免费PDF全文

刘宝林  桂暖银 《探矿工程》2000,(3):42-45

根据升降钻具的负载特点 ,动力驱动系统必须具备的 2个基本特性是硬的机械特性和近似恒功率的调速特性。给出了交流变频驱动钻机升降钻具机械化的技术方法和实例  相似文献   

钻机转盘用大型推力轴承淬火工艺分析及改进          下载免费PDF全文

关蜀军 《探矿工程》2000,(6):43-44

工程钻机及水井钻机转盘用大型推力轴承的加工比较困难,存在淬火变形问题,分析了轴承圈的淬火工艺及淬火变形产生的主要原因,通过设计心用简易淬火压床,改进淬火工艺,减小了轴承圈的变形,提高了制造质量。  相似文献   

水下作业工具液压动力源的研制   总被引：5，自引：0，他引：5  

刘志浩  高世伦 《海洋技术学报》2002,21(2):21-23

通过水下作业工具的有关技术的介绍 ,阐述了液压动力源的基本构成及工作原理 ,设计了水压力自动补偿器可消除深水压力对工具系统的影响 ,最后 ,经过试验验证了理论的正确性  相似文献   

A novel shear vane used to determine the evolution of hydraulic dredge tracks in sub-tidal marine sediments     

C. Hauton  D. M. Paterson 《Estuarine, Coastal and Shelf Science》2003,57(5-6):1151-1158

A novel shear vane is described which can be used to record the shear strength of discrete depth horizons of a variety of marine sediment types in situ. This vane, or modifications of it, has great potential in allowing measurement of in situ shear strength without requiring any samples to be removed from the sea bed, a process which can often destroy the fine structure of the sediment. The vane was used to monitor the change in sediment shear strength caused by a hydraulic dredge, which was used to fish razor clams (Ensis arcuatus) in a sheltered bay within the Clyde Sea area, Scotland. Data collected using this apparatus provided valuable and immediate information on the stratification of the sea bed post-dredging and allowed the evolution of the dredge track to be regularly monitored by divers over a period of 100 d.  相似文献   

Response of the Baltic Sea to climate change—theory and observations     

Anders Stigebrandt  Bo G. Gustafsson   《Journal of Sea Research》2003,49(4):243

The dynamics controlling the response of the Baltic Sea to changed atmospheric and hydrologic forcing are reviewed and demonstrated using simple models. The response time for salt is 30 times longer than for heat in the Baltic Sea. In the course of a year, the Baltic Sea renews most of its heat but only about 3% of its salt. On the seasonal scale, surface temperature and ice-coverage are controlled by the atmospheric conditions over the Baltic Sea as demonstrated by e.g. the strong inter-annual variations in winter temperature and ice-coverage due to variations in dominating wind directions causing alternating mild and cold winters. The response of surface temperature and ice-coverage in the Baltic Sea to modest climate change may therefore be predicted using existing statistics. Due to the long response time in combination with complicated dynamics, the response of the salinity of the Baltic Sea cannot be predicted using existing statistics but has to be computed from mechanistic models. Salinity changes primarily through changes in the two major forcing factors: the supply of freshwater and the low-frequency sea level fluctuations in the Kattegat. The sensitivity of Baltic Sea salinity to changed freshwater supply is investigated using a simple mechanistic steady-state model that includes baroclinic geostrophic outflow from the Kattegat, the major dynamical factor controlling the freshwater content in the Kattegat and thereby the salinity of water flowing into the Baltic Sea. The computed sensitivity of Baltic Sea surface salinity to changes of freshwater supply is similar to earlier published estimates from time-dependent dynamical models with higher resolution. According to the model, the Baltic Sea would become fresh at a mean freshwater supply of about 60 000 m³ s⁻¹, i.e. a 300% increase of the contemporary supply. If the freshwater supply in the different basins increased in proportion to the present-day supply, the Bothnian Bay would become fresh already at a freshwater supply of about 37 000 m³ s⁻¹ and the Bothnian Sea at a supply of about 45 000 m³ s⁻¹. The assumption of baroclinic geostrophic outflow from the Kattegat, crucial for the salinity response of the Baltic Sea to changed freshwater supply, is validated using daily salinity profiles for the period 1931–1977 from lightship Läsö Nord.  相似文献   

桶基平台负压沉贯过程汲水泵机的初步水力分析     

孙东昌  张亭健 《海洋科学进展》2000,18(4):46-50

对桶形基础平台负压沉贯过程中汲水泵机进行了初步水力分析,讨论了不同水深、不同泵机安装高度情况下,桶腔和泵机进口之间的压头关系.这些结果可作为实际工作中选择泵机类型及其安装高度的参考.  相似文献