Design And Performance Study Of Flowing Water Icing Test System

With the rapid development of science and technology,various countries have put their development strategic objectives from land to sea.However,with the current level of science and technology,there are also a series of constraints.Therefore,it is of great theoretical and practical significance to study the freezing growth characteristics of seawater.According to the characteristics of seawater flow in different sea areas,A laboratory device for simulating seawater freezing,namely the water tunnel freezing test bed,was set up,On the basis of the water tunnel icing test platform,a series of sea ice formation simulation tests are carried out.The details are as follows:(1)Numerical simulation of the foundation water tunnel device is carried out.Firstly,the contraction ratio of six different contraction sections is simulated and compared by numerical simulation method(4,5.29,6.25,7.29,8.41,9).The final shrinkage ratio is 6.25.At the same time,the velocity and pressure of the whole internal flow field are simulated to ensure that they meet the design requirements.Six sections of the test section of the tunnel body are cut every 10 mm,and the velocity nephogram is analyzed,so that a stable flow field can be obtained.(2)The structural design of water icing system in tunnel includes contraction section,corner(including 13 guide vanes inside),diffusion section,stabilization section,test section and auxiliary system.It can use the structural characteristics to simulate the flow state of seawater and ensure the uniformity and stability of the flow rate at the test section.Its external auxiliary system includes temperature monitoring system,cooling system,determination of water pump,etc.(3)Experimental sea ice preparation.When the temperature of the flow field in the test section is stable at 4-2? during sea ice preparation,the system starts to work.The preparation of sea ice is aimed at different working conditions,namely,three experimental flow rates(0.05m/s,0.1m/s,0.2m/s)and four salinity gradients(0,0.1%,0.2%,0.3%),and the three test temperatures set when the test time was initially controlled(-8?,-10?,-12?).Finally,36 groups of 12 kinds of sea ice samples were obtained.(4)The construction of sea ice density measurement system is mainly based on the limitation of sea ice density measurement.Therefore,a special solution was prepared,and viscosity test,density test and freezing point test were carried out on this solution.The results show that 85% glycerol-antifreeze solution meets the experimental conditions,and the density of sea ice samples is observed on the basis of densimeter.Finally,the law that the growth characteristics,internal structure and even mechanical properties of sea ice are affected by seawater velocity and salt content is obtained,which can provide a certain theoretical reference for the design and construction of offshore structures.