역전유동층 내에서의 유동해석 및 슬러리아이스 생성에 관한 실험적 연구

Abstract

and descent motion to be irregular by an ascent motion and fluid flow caused by the buoyancy of fluid substances after charging the fluid substances (plastic ball) that its density is lower than the fluid. The irregular flow of these fluid substances is referred to as reverse motion and the fluid layer produced by reverse motion is called the reversing flow.

In this experiment, the slurry ice production experiment within the reverse fluid layer was conducted through both the primary and secondary stages.

The primary stage of this experiment was about slurry ice production within the single tube. For slurry ice to be produced, the 20wt percent aqueous solution of ethylene glycol was used for fluid while Styrofoam balls for the reversing substance were used. In this experiment, the efficacy caused by changing the average velocity, ball filling rate, and ball size was investigated.

The secondary stage of this experiment was about slurry ice production within the tube bundle. For the slurry ice to be produced, the 20wt percent aqueous solution of ethylene glycol was used for fluid

The improvement of energy efficacy and the development of alternative energy sources are linked to environmental issues, including global warming which have turned out to be a very important challenging issues to the world recently. The overuse of fossil resources such as coal and kerosene has nearly exhausted the supply of raw materials and that leads to massive dioxide emissions as well, thus causing global warming.

The solution to these energy issues is not just limited to one country. As these global problems are increasingly being recognized as social, economic and political issues requiring international cooperation, careful and effective solutions for them are required.

New renewable energy sources as a suggested solution use energy to be possibly recycled, such as sunlight, waves, wind, terrestrial heat, rain and biological gases which produces electric energy.

The electric energy, as an environmental-friendly mobilization which doesn't emit greenhouse gases and noxious gases, such as CO2 emissions environmental-friendly machines using electric energy have rapidly increased not only in industrial fields, but also private fields.

The new energy issues, lack of power caused by the increased use of electric energy followed by these issues are raised. A lack of electrical power occurs especially during summer season which is caused by the increased use of air conditioners. Especially the increased use of maximum electricity in the daytime has risen as social issues, such as causing the suspension of power supply.

A lack of maximum electric use in the daytime can be solved by the ice storage cooling system that uses the unutilized energy during late night time periods and the ice storage cooling system can use not only the sensible heat of cold water, as well as the latent heat of phase changes in ice. Thus, it’s a cooperative system with high efficacy of energy use.

Especially the slurry ice typed ice storage system produces and stores the slurry ice in particle size from a micron to several microns. The heat exchange occurs since it transports to cooling air conditioning and its usefulness is highly satisfied.

The important technique of the slurry ice typed ice storage system is to produce high quality slurry ice. Currently, the commercialized production method for slurry ice is the scrapper type system. The scrapper type is a system that produces the slurry ice through continuously scrapping ice off by scrapper and additional power is needed to run the scrapper.

The purpose of this experiment was to increase the efficacy of the system by removing this additional scrapper motion power. Thus, this experiment was conducted by using a heat exchange in reverse flow so that slurry ice can be produced without using additional power.

The reversing flow makes fluid flow from the upper part to the bottom part

and polypropylene balls for the reversing substance were used. In this experiment, the efficacy caused by changing the average velocity, ball filling rate, and air filling rate was investigated.