VMFL049

VMFL049
Combustion in an Axisymmetric Natural Gas Furnace

Overview

Reference

K.C. Westbrook, L.F. Dryer, “Simplified reaction mechanism for the oxidation of hydrocarbon fuels in flames”, Combustion Science and Technology, Vol 27, pp. 31-43, 1981

T.P. Coffee, “A Lumped Parameter Code for Regenerative Liquid Propellant Guns”, BRL-TR-2703, U.S. Army Ballistic Research Laboratory, 1985

Solver Ansys Fluent

Physics/Models Turbulent non-premixed combustion, Eddy dissipation model, k-ε model

Target File

VMFL049_combustion.cas

Project Files Link to Project Files Download Page

Test Case

Non-premixed combustion in a natural gas fired furnace is modeled. The axisymmetric flow field is modeled by a 3° cylindrical domain. Fuel jet consists of natural gas modeled as 90% Methane and 10% Nitrogen by mass.

Figure 123: Flow Domain

Geometry	Boundary Conditions
Inner diameter of air annulus = 60 mm Outer diameter of air annulus = 100 mm Diameter of combustion chamber = 500 mm Length of chamber = 1700 mm	Air velocity at inlet = 34 m/s Fuel velocity at inlet = 7.1 m/s Wall temperature = 120 °C CH₄ Mass fraction at inlet = 0.90

Geometry

Boundary Conditions

Inner diameter of air annulus = 60 mm

Outer diameter of air annulus = 100 mm

Diameter of combustion chamber = 500 mm

Length of chamber = 1700 mm

Air velocity at inlet = 34 m/s

Fuel velocity at inlet = 7.1 m/s

Wall temperature = 120 °C

CH₄ Mass fraction at inlet = 0.90

Analysis Assumptions and Modeling Notes

The flow is steady. Reactions modeled using Eddy Dissipation Model. The domain is axisymmetric.

Results Comparison for Ansys Fluent

Figure 124: Comparison of the Mole Fraction of CH₄ Along the Axis

Comparison of the Mole Fraction of CH4 Along the Axis

Figure 125: Comparison of Temperature Along the Axis