Numerical Simulation and Simulation Calculation Technology
LY Power’s numerical simulation technology is mainly based on the platform of ANSYS-CFD. It can conduct numerical simulation calculation on new product or new technology through five steps, which are practical problem analyzing, geometric modeling, physics-math modeling, simulation calculation and performance analyzing. Combined together with secondary development of software interface（UDF、Chemkin） and mathematical model modification, it can make an accurate prediction on the the actual application effect of the new product or technology.
1.Flue gas velocity field prediction
2.Heating surface wall temperature distribution prediction
3.Heating surface slagginig prediction
4.Velocity field prediction
From the above velocity field, it can be seen that the different flow patterns of primary air in the burner (inward or outward) lead to significant differences in the flow field of furnace. The penetrability of primary air under working condition of left side is obviously higher than that of the right side.
Different flow patterns of burners lead to significant differences in flow field of furnace. The penetrability of primary air under working condition of left side is obviously higher than that of the right side.
5.O2 concentration field prediction
The distribution of pulverized coal in working conditions 1 and 2 leads to the difference of pulverized coal burning area in furnace, these two together result in different oxygen concentration distribution characteristics. The oxygen-poor region (dark blue) in the figure corresponds to the main region where pulverized coal combustion occurs.
6.Temperature field prediction
The different distribution of flow field, pulverized coal concentration and burning out makes the exothermic combustion of the pulverized coal in furnace present different characteristics and result in different temperature field distribution. The furnace temperature in working condition 2 is slightly higher than that in working condition 1 due to better-pulverized coal diffusion and burnout.
7.Pulverized coal particle distribution prediction
Different flow patterns of the burners lead to a significantly different distribution of pulverized coal concentration in furnace. The penetrability of pulverized coal in working condition 1 is significantly higher than that in working condition 2 so that a large amount of pulverized coal is concentrated in the center of furnace, while in working condition 2, pulverized coal is mainly distributed near the burner outlet.
(1) Different flow patterns of the burners lead to significant differences in the flow field in the furnace. The penetrability of primary air in working condition 1 is significantly higher than that in working condition 2.
(2) In working condition 1, the recirculation zone is located between the inward primary air and the outward secondary air, while in working condition 2, the recirculation zone is formed in the center.
8.CO emission distribution prediction
Due to the strong penetrability of pulverized coal in working condition 1, combustion occurs mostly in the center of furnace, where CO is produced. In working condition 2, due to the good diffusion characteristics of pulverized coal and the existence of a large central recirculation zone that is favorable for ignition, pulverized coal combustion and the CO generated from it are mostly near the burner outlet.
9.Furnace wall heat transfer prediction
Pulverized coal in working condition 1 has a stronger penetrability compared with working condition 2, and most of its combustion heat release occurs in the central area of the furnace, resulting in a less heat transfer to the front and rear walls. Meanwhile, due to the poor diffusion of pulverized coal and its poor mixture with air, more combustion and heat release will happen higher, so that the overall furnace wall heat transfer will also occur in a higher position.
10.Pulverizing system performance prediction
The application of numerical simulation technology can predict the separation efficiency of the dynamic/static separator of the mill, furnace wall abrasion, coal particle concentration distribution, moisture content of the pulverized coal after drying, and the distribution ratio of the air and coal flow to each pulverized coal pipe by the distributor.