Flow Analysis Through APH to ESP Flue Path in 270MW Fuel Fired Boiler Using Fluent and CFX

This is about the analysis on Flue path through APH to ESP Duct. The following field values are taken as boundary conditions for this analysis. For 270 MW coal fired boiler there are 6 nos of APH Hoppers to collect the Fly ash and those are directly connected with pneumatic conveying system. Ducts are connected with ESP in two passes. In this analysis only one pass is taken into observation keeping the other pass blocked.

• APH Outlet Pressure : -190 mmwc.
• ESP Inlet Pressure : -214 mmwc.
• Mass Flow Rate : 1161.9 TPH.
• APH Outlet Temperature : 133 Deg Celcius.
• Density of Flue : .834 kg/m3.

Results While Keeping Hopper Outlets Blocked

Pressure Analysis

Velocity Analysis

Velocity Pathlines in 2D View

Velocity Pathlines in 3D View

• Now we are having Hopper Outlet Pressure : -200  mmwc.

Results While Keeping Hopper Outlets Opened

Pressure Analysis

Velocity Analysis

Velocity Pathlines in 2D View

Velocity Pathlines in 3D View

Flow Analysis of Flue Path at Economiser to APH Duct for 270 MW Pulverised Coal Fired Boiler Using CFD and ANSYS

Flow analysis of Eco Duct is my power plant process-case study using computational fluid dynamics. Economiser to APH duct is an important as well as critical duct segment in balanced draft system where the Flue has very high temperature and also very high content of fly ash.This segment of duct contains a baffle system (Deflector) and 4 no of Hoppers to collect the Fly Ash.2-5% of total fly ash is collected by the hoppers and transported to the pneumatic fly ash conveying system. In this case study Ansys Workbench and ICEM CFD are used for solid modelling and mesh generation and CFX and FLUENT are used for analysis. The following site measurements are used for boundary conditions...

• Total Mass Flow Rate = 1113 TPH
• Pressure At Eco Outlet = -31 mmwc
• Pressure At APH Inlet = -70 mmwc
• Temperature At Eco Inlet = 461 Deg C
• Density of Flue = .835 kg/m3
• Flue Gas Viscosity = .000022 kg/m-s

Pressure and Velocity Characteristics while keeping the Hopper Outlet Blocked

Animation of Particle Flow in 2D according velocity profiles

Animation of Particle Flow in 3D according velocity profiles