Simulation Study Of The Effect Of Hole Structure On The Exothermic Performance Of Solid Thermal Storage Electric Boiler

It is found that most of the existing solid heat storage electric boilers are round pores,with a porosity of about 20%,and the internal temperature distribution of the heat storage body is uneven and the heat release completion is low after the heat release is completed,and it is of great significance to improve the heat release performance of the solid heat storage electric boiler to improve the utilization efficiency of new energy.Based on the problem that the heat release performance of the existing circular hole solid heat storage electric boiler needs to be improved,it is found that some scholars have proposed that the elliptical hole solid heat storage electric boiler has better heat release performance than the round hole,and on this basis,a kind of circle-elliptical alternating special-shaped hole is proposed.In order to study the influence of hole shape on the heat release performance of solid heat storage electric boiler,the physical model of three kinds of hole type heat storage brick with single hole channel is first established,and the temperature field and velocity vector distribution in the hole of three types of hole heat storage brick under the same heat release condition for 10 hours are analyzed by Fluent simulation software,and the heat release completion degree of heat storage brick is calculated.It is found that compared with the other two types of hole shapes,the radial velocity vector is generated in the hole,the convective heat transfer effect is better,and the heat release completion of the heat storage brick is higher.Then,the physical model of three kinds of hole-shaped solid heat storage electric boiler was established,and the temperature field distribution of three kinds of hole boiler heat storage body in four identical sections under the same heat release condition for 10 hours was compared and analyzed by Fluent simulation software,and the heat release completion degree and heat release uniformity of the boiler heat storage body were calculated.It was found that the average temperature of the heat storage body in the same section of the special-shaped hole was the lowest,and the heat release completion and heat release uniformity of the boiler heat storage body were the highest.Finally,the special-shaped hole electric boiler model with four porosities of 15%,20%,25% and 30% was established,and the simulation analysis under the same heat release condition for 10 hours was carried out,and the heat release completion degree and heat release uniformity of the boiler heat storage body were calculated.It was found that the heat release completion and heat release uniformity of the 25% porosity boiler heat storage body were the highest,but the ability to improve the porosity was limited compared with 20% and 30%.The results show that the pores are special-shaped pores,and the solid heat storage electric boiler with porosity in the range of 20%-25% is improved by11.15%-11.92% and the heat release uniformity is increased by 3.49%-5.11%compared with the existing 20% porosity round hole boiler.This study provides a reference for the optimal design of solid thermal storage electric boiler.