Research On Flow Characteristics And Cavitation Of Ice Slurry In Centrifugal Pump

Ice slurry is a good refrigerant and cold storage agent.It has the characteristics of small particle size,large specific surface area,good heat exchange performance,strong fluidity and pumpability.At present,many scholars at home and abroad have conducted research and analysis on the flow and heat transfer of ice slurry,but as pumpable ice,few studies have focused on the flow of ice slurry in centrifugal pumps.Centrifugal pumps are the power source for transporting ice slurry in cold storage air conditioners.It is also important to analyze the flow characteristics of ice slurry in centrifugal pumps.This paper first uses Pro / E software to perform a three-dimensional modeling of the full-flow channel of the selected centrifugal pump,and divides the calculation area and network of the flow channel in the centrifugal pump through the adaptive preprocessing software ICEM Division of the grid.Secondly,based on the research results of ice slurry flow and flow characteristics by domestic and foreign scholars,a suitable ice slurry twophase flow model was established.Then,the internal flow field of the centrifugal pump is solved based on pressure,three dimensions and steady state.The RNG k-ε turbulence equation is used and the SIMPLE algorithm is used to calculate the pressure-velocity coupling.The pressure distribution,velocity vector distribution and the distribution of ice crystal particles in the centrifugal pump were analyzed under different flow conditions.By changing the flow conditions and several numerical calculations,the performance characteristic curve of the centrifugal pump when transporting ice slurry with an ice content of 10% was obtained,and the performance curve of this centrifugal pump when transmitting clean water was compared and analyzed.By changing the ice content of the ice slurry,the performance curves of the centrifugal pump for delivering ice slurry with different ice content under the design flow conditions were obtained.Finally,the solid phase and water phase of ice crystal particles are regarded as a homogeneous slurry.The Euler–Euler model is used to establish a bubble(G)-water(L)-ice crystal particle(S)three-phase flow model.A centrifugal pump with an ice slurry rate of 10% was subjected to unsteady cavitation simulation calculations.The pressure distribution and bubble distribution in the centrifugal pump under different flow conditions were analyzed.By adjusting the total inlet pressure,the NPSH-H curve and the necessary cavitation margin are obtained.The research in this paper revealed the flow characteristics and cavitation law of ice slurry in the centrifugal pump,and to provide a basis for designers when selecting an ice slurry pump.