Study on ICE Slurry Fabricating System Based on AIR JET Lifting Supercooled State
|Course||Refrigeration and Cryogenic Engineering|
|Keywords||Ice Slurry Supercooled Water Supercooled State Relieve|
Energy problem is one of the three biggest problems of the present world. For our country, since our per-capita amount of energy is relatively poor, energy problem is particularly pronounced. China is now in a period of rapid development, and the demand of energy is also rapidly increased. Our building energy consumption takes the largest proportion of our total energy consumption. Heating and air conditioning energy consumption is the major component of building energy consumption, and both have the characteristic of big circadian gap.Ice thermal storage technology can achieve energy’s rational allocation, improve the stability of the utilisation of electrical energy.This technology can also adapt to the policy of electricity price difference between day and night time, achieve enormous economic benefits. Ice slurry thermal storage is the latest and the most efficient cold storage method of dynamic ice thermal storage technology, many scholars have done a lot of researches on this method during recent years.This paper introduces the research status of ice slurry fabricating system, emphatically introduces the working principle of super cooling type ice-slurry fabricating system, sums up the existing problems of super cooling type ice-slurry fabricating system and previous research results on these problems. The author of this paper designs a super cooling type ice-slurry fabricating system for experiment according to the basic theory of ice slurry preparation and results from previous studies. And finds out the system’s maximum supercooled temperature and stable supercooled temperature range under specific conditions (water’s flow rate is52L/min; first cooling medium flow’s velocity is1.3m/s and its temperature is-8.0℃).The author also does some preliminary researches on the effect of disturbance to the supercooled state of supercooled water, and lifts the supercooled state of supercooled water by injecting compressed air into supercooled water. The experiment results show that:(1) For a super cooling type ice-slurry fabricating system, when the water flow and first cooling medium flow’s conditions are given, the maximum supercooled temperature is a certain value, and the supercooled water whose supercooled degree is lower than the maximum supercooled degree has a certain stability.(2) The disturbance could relieve the supercooled state of supercooled water.For different supercooled degrees, disturbance quantity required to relieve the supercooled state is different, the higher the supercooled degree, the smaller quantity of disturbance is required to relieve the supercooled state. The biggest disturbance of the system determines the maximum supercooled temperature that the system can achieve.(3) The disturbance produced by compressed air injected into the supercooled water can relieve the supercooled state. Under different supercooled degrees, the required air jet kinetic energy is different; the higher the supercooled degree, the smaller air jet kinetic energy is required; when the supercooled degree is higher than1.5℃, with the increase of supercooled degree, the required air jet kinetic energy decreases sharply.(4) Using compressed air to relieve the supercooled state of supercooled water will form gas-liquid-solid three-phase uniformly mixed ice slurry which is in a state of high-speed flowing. The ice particle in the ice slurry has a very small size, just about tens of microns, and its distribution is very uniform. Since ice-slurry’s speed is very fast, these crystals cannot adhere to the pipe wall and cause ice blockage. So the ice-slurry can be continually cooled to improve IPF.A kind of ice slurry fabricating system based on the results of experiment is put forward.