Design and Experimental Research on Deep Water Pressure Resistance System of Argo Float

2019 ◽  
Vol 83 (sp1) ◽  
pp. 116
Author(s):  
Hanling Wu ◽  
Yanjun Liu ◽  
Gang Xue ◽  
Fengxiang Guo ◽  
Zhitong Li ◽  
...  
2014 ◽  
Vol 535 ◽  
pp. 738-743
Author(s):  
Lei Liu ◽  
Shen Zhang Liu ◽  
Hong Quan Zhao

compound sensitizing agent is an important component of the emulsion explosive, by using reusable experiment device to simulate the deep charging environment, study compound sensitizing agent on the properties of emulsion explosive deep water pressure resistance. Experimental results show that the mixed sensitizing, the deep water pressure resistance of three kinds of emulsion explosive performance award to him a bad order: glass microspheres + perlite + sodium nitrite sensitization, glass microspheres + perlite and sensitizing sodium nitrite sensitization. Compound containing glass microspheres sensitizer, the measurement of explosive performance closer to sensitization performance when only glass microspheres, perlite, the addition of sodium nitrite on the explosive performance contribution is small. Sodium nitrite and perlite mixed sensitizing, explosive detonation "hot spots", first class formation is chemical sensitization is given priority to, only a minority of perlite as "hot spots", the measurement of explosive performance closer to use sodium nitrite sensitization performance.


2016 ◽  
Vol 31 (0) ◽  
pp. 161
Author(s):  
Atsuhisa OGAWA ◽  
Kazumasa KUSUDO ◽  
Ryo NISHIZATO ◽  
Naoyuki YAGUCHI ◽  
Ken-ichi KOJIMA ◽  
...  

2021 ◽  
Author(s):  
Mal Heron

Seismic signals provide an effective early detection of tsunamis that are generated by earthquakes, and for epicentres in the hard-rock subduction zones there is a robust analysis procedure that uses a global network of seismometers. For earthquakes with epicentres in soft layers in the upper subduction zones the processes are slower and the seismic signals have lower frequencies. For these soft-rock earthquakes a given earthquake magnitude can produce a bigger tsunami amplitude than the same earthquake magnitude in a hard rock rupture. Numerical modelling for the propagation from earthquake-generated tsunamis can predict time of arrivals at distant coastal impact zones. A global network of deep-water pressure sensors is used to detect and confirm tsunamis in the open ocean. Submarine landslide and coastal collapse tsunamis, meteo-tsunamis, and other disturbances with no significant seismicity must rely on the deep-water pressure sensors and HF radar for detection and warning. Local observations by HF radar at key impact sites detect and confirm tsunami time and amplitude in the order of 20–60 minutes before impact. HF radar systems that were developed for mapping the dynamics of coastal currents have demonstrated a capability to detect tsunamis within about 80 km of the coast and where the water depth is less than 200 m. These systems have now been optimised for tsunami detection and some installations are operating continuously to provide real-time data into tsunami warning centres. The value of a system to warn of hazards is realised only when coastal communities are informed and aware of the dangers.


2012 ◽  
Vol 16 (11) ◽  
pp. 4205-4221 ◽  
Author(s):  
F. Cervi ◽  
F. Ronchetti ◽  
G. Martinelli ◽  
T. A. Bogaard ◽  
A. Corsini

Abstract. Changes in soil water content, groundwater flow and a rise in pore water pressure are well-known causal or triggering factors for hillslope instability. Rainfall and snowmelt are generally assumed as the main sources of groundwater recharge. This assumption neglects the role of deep water inflow in highly tectonized areas, a factor that can influence long-term pore-pressure regimes and play a role on local slope instability. This paper aims to assess the origin of groundwater in the Ca' Lita landslide (northern Italian Apennines) and to qualify and quantify the aliquot attributable to deep water inflow. The research is essentially based on in situ monitoring and hydrochemical analyses. It involved 5 yr of continuous monitoring of groundwater levels, electrical conductivity and temperature and with groundwater sampling followed by determination of major ions (Na+, K+, Mg2+, Ca2+, Cl−, HCO3−, SO42−), tracers (such as Btot and Sr2+), and isotopes (δ18O, δ2H and 3H). Leaching experiments on soil samples, hydrochemical modelling and water recharge estimation were also carried out. Results show that the groundwater balance in the Ca' Lita landslide must take into account an inflow of deep and highly mineralised Na-SO4 water (more than 9500 μS cm−1) with non-negligible amounts of Cl− (up to 800 mg l−1). The chemical and isotopic fingerprint of this water points to oilfield water hosted at large depths in the Apennine chain and that uprises through a regional fault line crossing the landslide area. It recharges the aquifer hosted in the bedrock underlying the sliding surface (at a rate of about 49 000–85 700 m3 yr−1) and it also partly recharges the landslide body. In both the aquifers, the hydrochemical imprint of deep water mixed with rainfall and snowmelt water was observed. This indicates a probable influence of deep water inflow on the mobility of the Ca' Lita landslide, a finding that could be applicable to other large landslides occurring in highly tectonized areas in the northern Apennines or in other mountain chains. The paper demonstrates that hydrochemistry should, therefore, be considered as a valuable investigation method to define hydrogeological limits and the groundwater sources in hillslope and to assess groundwater flow patterns in deep-seated landslides.


ce/papers ◽  
2021 ◽  
Vol 4 (2-4) ◽  
pp. 2527-2534
Author(s):  
Maciej Chrzanowski ◽  
Perla El Boueiz ◽  
Rui Matos ◽  
Heiko Zillgen ◽  
Boris Even

2011 ◽  
Vol 243-249 ◽  
pp. 4723-4727
Author(s):  
Cong Huan Le ◽  
Hong Yan Ding ◽  
Guo Hai Dong ◽  
Pu Yang Zhang

Internal air pressure and water pressure of the buckets foundation, acceleration and dragging force of the 4-bucket foundation platform were determined to analyze the influences of wave height on towing when 4-Bucket foundation platform is towing in conditions of a certain towing velocity, mooring point position and draught in different regular waves based on the model test. Comparing platform towing in following and head waves, the heave motion of the latter is more strenuous than that of the former; the stability and seakeeping of the former is better than those of the latter. Roll motion, pitch motion and heave motion appear aggravate phenomenon with the increase of wave height.


2017 ◽  
Vol 310 ◽  
pp. 134-142 ◽  
Author(s):  
Chao-Hua Xue ◽  
Min Li ◽  
Xiao-Jing Guo ◽  
Xing Li ◽  
Qiu-Feng An ◽  
...  

2021 ◽  
Vol 9 (6) ◽  
pp. 563
Author(s):  
Guangyu Shi ◽  
Alexandros Priftis ◽  
Yan Xing-Kaeding ◽  
Evangelos Boulougouris ◽  
Apostolos D. Papanikolaou ◽  
...  

This paper numerically investigates the resistance at full-scale of a zero-emission, high-speed catamaran in both deep and shallow water, with the Froude number ranging from 0.2 to 0.8. The numerical methods are validated by two means: (a) Comparison with available model tests; (b) a blind validation using two different flow solvers. The resistance, sinkage, and trim of the catamaran, as well as the wave pattern, longitudinal wave cuts and crossflow fields, are examined. The total resistance curve in deep water shows a continuous increase with the Froude number, while in shallow water, a hump is witnessed near the critical speed. This difference is mainly caused by the pressure component of total resistance, which is significantly affected by the interaction between the wave systems created by the demihulls. The pressure resistance in deep water is maximised at a Froude number around 0.58, whereas the peak in shallow water is achieved near the critical speed (Froude number ≈ 0.3). Insight into the underlying physics is obtained by analysing the wave creation between the demihulls. Profoundly different wave patterns within the inner region are observed in deep and shallow water. Specifically, in deep water, both crests and troughs are generated and moved astern as the increase of the Froude number. The maximum pressure resistance is accomplished when the secondary trough is created at the stern, leading to the largest trim angle. In contrast, the catamaran generates a critical wave normal to the advance direction in shallow water, which significantly elevates the bow and creates the highest trim angle, as well as pressure resistance. Moreover, significant wave elevations are observed between the demihulls at supercritical speeds in shallow water, which may affect the decision for the location of the wet deck.


2016 ◽  
Vol 705 ◽  
pp. 350-354
Author(s):  
Hui Xie ◽  
Ying Chen

High-water material is a kind of new inorganic nonmetal material which mainly used in coal mine goaf filling. In order to simulate the real stress conditions of this material in goaf filling, the creep tests of high-water material in real pressure water environment were conducted and the creep laws were also researched. The results showed that water environment was conductive to maintaining and developing the strength of high-water material, and pressure water environment can improve the carrying capacity and long-term strength of high-water material. The deformation of steady creep period decreased while water pressure increased. And strain increasing caused by axial compression was less than strain increasing caused by water pressure. The time needed from starting to steady creep period was longer when water pressure was bigger.


Author(s):  
Chongyao Zhou ◽  
Liang Zhang ◽  
Yongtian Kang ◽  
Yan Qu ◽  
Kevin Huang ◽  
...  

Umbilical is the key actor connecting the subsea devices on the seabed to the platform, and acting like a neural line transforming the information from the central control system on platform to the subsea control elements. Normally, according to the applied chemical reagent and hydraulics control fluid transmitting element, the umbilical is divided into two types for alternative depths, one consists with hoses for shallow water or medium water application, and the other utilizes the super duplex steel tubes for all depth water application. The main argument for using steel over thermoplastic hoses would be chemical resistance and hydraulic response time (where hose performance is poor). However, the hose will have more flexibility than steel tube, which is also easier for manufacture. If the umbilical with hoses can be used in deeper water condition, the cost will decrease greatly. In order to strengthen the hose structure for deep water use (up to 1000m twice the prior record), this paper will focus on the study of a possible strengthened structure implanting into the hoses to increase the outer pressure resistance capacity, which will increase the whole outer pressure resistance performance of umbilical finally. The thermoplastic hose with strengthened structure will enable the use of thermoplastic hoses in deeper water.


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