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V. Kirubakaran and D. S. Bhatt
overall performance of an engine. The flow field inside the combustor is very complex
in nature because of its turbulent flow field. The gas turbine combustor has number
of sub-components like diffuser, snout, swirler, flame tube and annulus. Because
of this complex flow pattern inside the combustor, there is a need for detailed nonreacting flow analysis before dealing with reacting mixture for a better understanding
of combustion physics. In literature, the non-reacting flow analysis in the gas turbine
combustor was carried out by numerous researches [5–13]. Among this, a notable
work has been carried by Anand et al., wherein detailed 3D flow has been simulated
inside an annular combustor using a 20° sector for analysis. The k-ε RNG model was
used to model turbulence. The total pressure loss of the combustor varied from 4.41
to 9.87% for a given set of input velocity 158.8–238.20 m/s. Most of the previous
studies are on a large scale combustor employed in high power gas turbines. Using
the same principles, a small swirl combustor of 3 kW thermal capacity is designed.
In this present study, the focus is to investigate a cold flow analysis to study the flow
pattern inside the newly designed small size can combustor and measure the pressure
loss.
2 Combustor Geometry
An in-house designed can combustor includes diffuser, snout, swirler, flame tube
and annulus. The conical diffuser with 24.2° divergence angle is used in the present
study. The snout has a divergence angle of 24.8°; the axial swirler has 8 flat vanes
inclined at an angle of 45°. The flame tube has 265 mm length and 46 mm diameter;
it has primary zone having 88 number of 2 mm holes arranged in 4 rows, secondary
zone having 60 number of 3 mm holes arranged in 4 rows and dilution zone having
24 number of 2 mm holes arranged in 3 rows. The outer annulus has 300 mm of
length with 72 and 44 mm of inlet and outlet diameter. The overall thickness of can
combustor is maintained as 2 mm thickness. The dimensional detail of can combustor
is given in Fig. 1.
Fig. 1 Dimension details of can combustion chamber (all dimensions are in mm)
V. Kirubakaran and D. S. Bhatt
overall performance of an engine. The flow field inside the combustor is very complex
in nature because of its turbulent flow field. The gas turbine combustor has number
of sub-components like diffuser, snout, swirler, flame tube and annulus. Because
of this complex flow pattern inside the combustor, there is a need for detailed nonreacting flow analysis before dealing with reacting mixture for a better understanding
of combustion physics. In literature, the non-reacting flow analysis in the gas turbine
combustor was carried out by numerous researches [5–13]. Among this, a notable
work has been carried by Anand et al., wherein detailed 3D flow has been simulated
inside an annular combustor using a 20° sector for analysis. The k-ε RNG model was
used to model turbulence. The total pressure loss of the combustor varied from 4.41
to 9.87% for a given set of input velocity 158.8–238.20 m/s. Most of the previous
studies are on a large scale combustor employed in high power gas turbines. Using
the same principles, a small swirl combustor of 3 kW thermal capacity is designed.
In this present study, the focus is to investigate a cold flow analysis to study the flow
pattern inside the newly designed small size can combustor and measure the pressure
loss.
2 Combustor Geometry
An in-house designed can combustor includes diffuser, snout, swirler, flame tube
and annulus. The conical diffuser with 24.2° divergence angle is used in the present
study. The snout has a divergence angle of 24.8°; the axial swirler has 8 flat vanes
inclined at an angle of 45°. The flame tube has 265 mm length and 46 mm diameter;
it has primary zone having 88 number of 2 mm holes arranged in 4 rows, secondary
zone having 60 number of 3 mm holes arranged in 4 rows and dilution zone having
24 number of 2 mm holes arranged in 3 rows. The outer annulus has 300 mm of
length with 72 and 44 mm of inlet and outlet diameter. The overall thickness of can
combustor is maintained as 2 mm thickness. The dimensional detail of can combustor
is given in Fig. 1.
Fig. 1 Dimension details of can combustion chamber (all dimensions are in mm)