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S. N. Mahottamananda et al.
θ
Spray cone angle
C d Discharge coefficient
m Mass flow rate of water
d 0 Outer diameter of the plug type swirl nozzle exit
d i
Inner diameter of the plug type swirl nozzle exit
ρ f Density of working fluid
P Pressure drop across the injector
1 Introduction
Swirl injector atomization process is a critical performance parameter of gas turbine
combustion chamber as well as various liquid and hybrid rocket combustion chambers. The advantage of using swirl injectors is the reduction of boundary layer thickness of combustion chamber walls and increasing the stay time of the injecting fluid,
leading to good mixing and efficient combustion [1]. The atomization process of swirl
injector is evaluated by various parameters namely liquid sheet break up length, spray
cone angle, discharge coefficient, and volumetric flow of injector. Over the years,
many experimental and numerical studies were carried out on swirl injector. The
number of inlet tangential ports has a direct effect on spray characteristics. Yule
et al. [2] did experiments on spray characteristics of swirl injectors with different
numbers of inlet tangential ports. They discovered that the injector with two inlet
tangential ports reduces the droplet size than a single inlet injector with constant inlet
area. Hamid [3]. done research on the effect of inlet slot number on spray cone angle.
They found six inlet slot injector produces a higher spray cone angle compared with
other injectors. Mat Rashid et al. [4]. carried out experimental work on the effect
of inlet slot number on discharge coefficient and spray cone angle. They discovered
that the effect of injection pressure on spray cone angle is more prominent at a lower
range of injection pressure and higher number of inlet slots. The lesser number of
inlet slots and higher injection pressure of inlet slots lead to less discharge coefficient.
Present experimental study focuses on the effect of number of inlet tangential
ports and their port angle on spray characteristics like liquid sheet breakup length,
spray cone angle, discharge coefficient, volumetric flow. Spray characteristics of
swirl injector have a direct influence on combustion chamber design parameters like
combustion chamber length and diameter. Three plug type swirl injector configurations are used namely SW1, SW2, and SW3. The comparison is made between
SW1and SW2 as well as SW1 and SW3, to evaluate the effect of number of tangential
port and tangential port angle on spray characteristics.
S. N. Mahottamananda et al.
θ
Spray cone angle
C d Discharge coefficient
m Mass flow rate of water
d 0 Outer diameter of the plug type swirl nozzle exit
d i
Inner diameter of the plug type swirl nozzle exit
ρ f Density of working fluid
P Pressure drop across the injector
1 Introduction
Swirl injector atomization process is a critical performance parameter of gas turbine
combustion chamber as well as various liquid and hybrid rocket combustion chambers. The advantage of using swirl injectors is the reduction of boundary layer thickness of combustion chamber walls and increasing the stay time of the injecting fluid,
leading to good mixing and efficient combustion [1]. The atomization process of swirl
injector is evaluated by various parameters namely liquid sheet break up length, spray
cone angle, discharge coefficient, and volumetric flow of injector. Over the years,
many experimental and numerical studies were carried out on swirl injector. The
number of inlet tangential ports has a direct effect on spray characteristics. Yule
et al. [2] did experiments on spray characteristics of swirl injectors with different
numbers of inlet tangential ports. They discovered that the injector with two inlet
tangential ports reduces the droplet size than a single inlet injector with constant inlet
area. Hamid [3]. done research on the effect of inlet slot number on spray cone angle.
They found six inlet slot injector produces a higher spray cone angle compared with
other injectors. Mat Rashid et al. [4]. carried out experimental work on the effect
of inlet slot number on discharge coefficient and spray cone angle. They discovered
that the effect of injection pressure on spray cone angle is more prominent at a lower
range of injection pressure and higher number of inlet slots. The lesser number of
inlet slots and higher injection pressure of inlet slots lead to less discharge coefficient.
Present experimental study focuses on the effect of number of inlet tangential
ports and their port angle on spray characteristics like liquid sheet breakup length,
spray cone angle, discharge coefficient, volumetric flow. Spray characteristics of
swirl injector have a direct influence on combustion chamber design parameters like
combustion chamber length and diameter. Three plug type swirl injector configurations are used namely SW1, SW2, and SW3. The comparison is made between
SW1and SW2 as well as SW1 and SW3, to evaluate the effect of number of tangential
port and tangential port angle on spray characteristics.