Experimental Investigation of the Effect of Single and Twin Bluff

Bodies on the Turbulent Flow in an Asymmetric Rectangular Diffuser

SOMNATH BHATTACHARJEE1, ARINDAM MANDAL2, RABIN DEBNATH3

SNEHAMOY MAJUMDER4

1Department of Computer Science and Engineering, Jadavpur University, 188, Raja S.C.Mullick

Road, Kolkata- 700 032, West Bengal, INDIA

2Department of Mechanical Engineering, Heritage Institute of Technology, Chowbaga Road,

Anandapur, P.O.: East Kolkata Township, Kolkata-700107, INDIA

3 Directorate of Industrial Training, Government of West Bengal, Karigori Bhavan, Pin-700 160, West

Bengal, INDIA

4Department of Mechanical Engineering, Jadavpur University, 188, Raja S.C. Mullick Road, Kolkata-

700032, INDIA

Abstract: - Experimental investigation of the effect of bluff bodies on the turbulent flow through an asymmetric

diffuser has been carried out. The rectangular diffuser is designed and made keeping similarity to that used by

Buice and Eaton, [1], having an inclination angle of 10°. Three geometrical configurations have been selected

for the experimentation. (I) At first the experiment has been carried out for the validation of the present results

with Buice and Eaton, [1], placing no bluff body at all. (II) Thereafter measurements have been carried out by

placing a single bluff body on the horizontal floor of the diffuser to estimate the effect of the bluff body on the

downstream flow. (III) Finally, two identical bluff bodies are placed on the horizontal floor of the diffuser and

experimental work has been carried out in order to investigate the effect of the existence of two bluff bodies on

the downstream flow through the diffuser. The present results agree well with the results of Buice and Eaton,

[1], to show that the recirculation zone appears just adjacent to the inclined plane when there is no bluff body in

a diffuser. Also, the detailed investigation for velocity of flow field, distribution of skin friction factor along

with uncertainty analysis as well as the correlation between friction factor and Reynolds Number have been

carried out in the research paper.

Key-Words: - Bluff body, Diffuser, Recirculation, Reynolds number, Skin friction Coefficient, Bulk Average

Velocity.

Received: March 28, 2022. Revised: October 25, 2022. Accepted: November 26, 2022. Published: December 31, 2022.

1 Introduction

The axi-symmetric rectangular flow has gotten

attention of researchers long ago.The characteristics

of air flow in a rectangular two dimensional diffuser

with fully developed inlet flow condition have been

measured by Obi, Aoki and Masuda, [2]. The

authors in [2], have experimentally investigated the

flow separation and recirculation region generated

in the diffuser of high aspect ratio. Obi, Ohizumi,

Aoki and Masuda, [3] have also examined two-

dimensional separated flow in an asymmetric

diffuser having fully developed inflow conditions

with diffuser inclination angle 10o and an expansion

ratio of 4.7. The authors have measured the mean

velocities, turbulent quantities and observed the

separation occurred at halfway downstream.

Gullman-Strand, Tӧrnblom, Lindgren, Amberg and

Johansson, [4], have considered the divergent angle

of the diffuser as 8.5o for reducing the size of the

separated region and accordingly, a high aspect ratio

of the diffuser results achieving a high degree of

two-dimensionality of the average flow. They have

also made comments that fully attached flow can

occur for the angle around 7o. Buice and Eaton, [1],

have experimentally examined asymmetric plane

diffuser flow and estimated the recirculation zones.

Present authors have been motivated by their very

unique and high quality experimental results and

give effort to validate their experimental results

considering the same aspect ratio and flow

conditions through the diffuser. Earlier,

experimental research works had been performed on

International Journal on Applied Physics and Engineering

DOI: 10.37394/232030.2022.1.7

Somnath Bhattacharjee, Arindam Mandal,

Rabin Debnath, Snehamoy Majumder

E-ISSN: 2945-0489

Volume 1, 2022

turbulent flows by Okwuobi and Azad, [5] and Azad

and Kassab, [6]. According to their investigation,

sudden change of adverse pressure gradient at the

diffuser throat causes the downstream as mean and

turbulent flow fields. Bhattacharjee, Debnath, Roy

and Majumder, [7], have experimentally studied the

turbulent air flow through a two dimensional

asymmetric rectangular diffuser. Majumder, Roy,

Bhattacharjee and Debnath, [8], have investigated

experimentally the turbulent flow behaviour of air

inside a diffuser with an inclination angle of 15°.

Coller, [9], has defined the diffuser as an expanding

section of a flow-carrying duct used to slow the

mean flow. It gives effect in the conversion of

kinetic energy to potential energy causing the rise of

pressure in the downstream region. Analytical

research work on turbulent separated flows in an

axi-symmetric diffuser has also been carried out by

Sagar, Paul and Jain, [10]. In [10] the authors have

narrated that the pressure-induced separation begins

in a diffuser with the increase of its half-angle.

Mandal, Bhattacharjee, Debnath, Majumder and

Roy, [11], have explained that the turbulent flow

and boundary layer separation are observed in many

industrial applications. Hwang, Chow and Peng,

[12], have investigated numerically that the

recirculation length decreases with the increase of

the length of the bluff body whereas Antoniou and

Bergeles, [13], have experimentally studied that by

the enhancement of the aspect ratio, the flow

reattaches at the downstream with the reduction of

turbulence scale and recirculation length. Hwang,

Chow and Chiang, [14], have analyzed numerically

the turbulent flow around a surface-mounted two-

dimensional bluff body of varying length. They

have observed that the length of the re-circulating

zone remains unchanged with the variation of the

length of bluff body in the upstream of flow. In the

downstream of flow, the length of the re-circulating

region depends on the length of the bluff body.

Reattachment on the upper side of the bluff body

influences the velocity boundary layer developed at

the downstream region. This is valid as the length of

bluff body increases. According to [12] the authors

have remarked that the length of re-circulating

zones depends on the ratio of the boundary layer

thickness to the bluff body’s height and on the

geometry of the bluff body. Bergeles and

Athanassiisdis, [15], have experimentally evaluated

the lengths of the re-circulating regions in front of

and behind the bluff body. Benodekar, [16], has

mentioned that Reynolds number has negligible

effect on separation in the case of turbulent flow.

Baetke, Werner and Wengle, [17], have remarked

that wall boundary conditions at sharp corners

strongly control separation of flow. Das, Ghosh and

Singh, [18], have asserted in their literature that the

flow field around the building or structure situated

on the surface boundary layer is fully turbulent and

complex with separations at each surface of the

building. Bhattacharjee, Debnath, Mandal,

Majumder and Roy, [19], have observed through the

experimental work using two bluff bodies of

different sizes in a rectangular diffuser and

recirculation zones are distinctly pointed out. Mehdi

and Mushatet, [20], have pronounced that the

separation of boundary layer and recirculation zones

behind the bluff bodies mainly depend on the

spacing between the bluff bodies. Liu, [21], has

analyzed the numerically simulated flow around the

cylinders of different shapes changing from square

to circle. The author has made the opinion that the

drag coefficient and reattachment length decreases

independent of the Reynolds number. It is also

commented that the drag coefficient of a rounded-

corner square cylinder can be lower than the circular

cylinder of the same size. Poussou and Plesniak,

[22], have observed experimentally the wake

formed due to a bluff body propagating through a

recirculating flow using Particle Image Velocimetry.

Lander, Letchford, Amitay and Kopp, [23], have

investigated the influence of bluff body shear layer

formation and the resulting impact on flow

characteristics using two-dimensional square prism

with the help of Particle Image Velocimetry.

Bandyopadhyay, Sarkar, Roy and Chanda, [24],

have experimentally found the flow field in a

rectangular diffuser using a bluff body. The authors

have remarked that the boundary layer thickness is

somewhat lower at higher inlet velocity and

maximum momentum occurs near the bluff body.

Nasr, Abdel-Fattah and EI-Askary, [25], have

investigated the effect of the number of ribbed walls

on heat transfer surface and friction property. In

[25] the authors have commented that ribs mounted

on the heat transfer surface make disturbance on the

boundary layer growth and augmentation of heat

transfer from the surface to the fluid and better

mixing is possible. The useful scientific idea

regarding flow separation and recirculation bubble

formation near the bluff bodies is still very scarce in

the published literature. The present experimental

work is associated with the diffusing air fluid flow

with generation of recirculation. The main objective

of the present study is to explore the turbulent air

flow behaviour experimentally at normal

atmospheric pressure and temperature in an

asymmetric two dimensional diffuser of rectangular

cross section fitted with single and twin bluff bodies

respectively.

International Journal on Applied Physics and Engineering

DOI: 10.37394/232030.2022.1.7

Somnath Bhattacharjee, Arindam Mandal,

Rabin Debnath, Snehamoy Majumder

E-ISSN: 2945-0489

Volume 1, 2022

2 Experimental Method

The experiment has been conducted in an

asymmetric horizontal rectangular diffuser

maintaining similarity with the geometry of the

experimental set up used by Buice and Eaton, [1].

The lower portion of the diffuser is horizontal and

its upper one is tilted. The inlet section of the

diffuser is 0.015 × 0.200 m which is combined with

the outlet section of the air blower. The aspect ratio

of the diffuser and the horizontal length of the inlet

channel are (13.33:1) and 0.83 m respectively. For

maintaining similarity with the experimental set up

used by Buice and Eaton, [1], the normal height of

the downstream tail end of the diffuser is

H7.4

and

the axial length of the diffuser is

H21

with an

inclination angle of 10°. The outlet section of the

diffuser of rectangular shape is 0.07 × 0.2 m

extending the length up to

H77

. Both the upper and

lower walls of the diffuser are made of 0.006 m

thick Plexi-glass sheet. The side walls of the

diffuser are constructed of plain transparent glass

sheet of 0.004 m thickness. The turbulent air from

the blower finally enters the inlet section of the

diffuser after passing through the vibration absorber,

wire-mesh and honey comb chamber accommodated

in between the blower and the diffuser. This type of

construction ensures the uniform turbulent fluid

flow through the inlet section of the diffuser. The

blower which is coupled with a D.C. motor supplies

air to the diffuser. Pressure Transducer is used in the

experimental work for measuring stagnation and

static pressure difference at a certain location inside

the diffuser. The specification of the Pressure

Transducer used is as follows: Model-CP300-HOP,

Sl.No.-12040821, Type-304, and Range: -

10000/10000 Pa, Air velocity range - 2 to 100 m/s

with accuracy: ± 0.5% of reading ± 1 Pa. The

measured pressure difference is utilised to calculate

the axial mean velocity of the turbulent fluid flow.

The calibrated Pitot tube has been used to determine

pressure heads. The probe is introduced from

numbers of drilled holes situated over the top

inclined surface along the mid-stream plane

XX

at different station locations along the

diffuser length. Pressure differences (Δp Pa)

between the stagnation and static pressures are

calculated at various vertical heights measured from

the bottom horizontal wall by using Pitot tubes

mounted on a traversing equipment. Thermometer

and Barometer are employed for taking the reading

of local atmospheric temperature and pressure inside

the laboratory. The diffuser is installed perfectly on

a wooden frame structure. The working fluid is air

assuming its density ρ = 1.132 kg/m3 at normal

room temperature (300 K) and pressure (101.6 KPa)

inside the laboratory.

At first, the current experimental work for validation

of the results using the set up without a bluff body

has been carried over only at Reynolds number

equal to 1.367 × 104. The two-dimensional

parameters measured for the mean turbulent fluid

velocity profile have been plotted comparing the

benchmark experimental results of Buice and Eaton,

[1].

Secondly, a single polished wooden bluff body

made of dimension 0.20 × 0.02 × 0.02 m is placed

over the horizontal bottom wall at a distance of

0.18m from the inlet section of the diffuser. For

third experimentation work utilising the same set up,

two wooden bluff bodies, each of equal dimensions

of 0.20 × 0.02 × 0.02 m, are placed on the bottom

wall at the distances of 0.18 m and 0.30 m

respectively from the inlet section of the diffuser

and a clear gap existing between them is 0.12 m. For

second and third experimental works the inlet flow

condition is turbulent with Re = 1.367× 104, 1.749×

104 and 1.833× 104 respectively. Reynolds numbers

are calculated based on the inlet height of the

diffuser and axial mean flow velocity. Here also

two-dimensional measurements have been taken in

the mid-stream plane

XX 

. The velocity

distribution curves are obtained at different stations

along the horizontal length of the diffuser.

The equations for the mean velocity of fluid u, uavg

m/s, Reynolds numbers and coefficient of skin

friction of the working fluid flowing passing

through the diffuser Cf are hereby given below:

81.92







(1)





Re

(2)

 

avg

dydu







(3)

International Journal on Applied Physics and Engineering

DOI: 10.37394/232030.2022.1.7

Somnath Bhattacharjee, Arindam Mandal,

Rabin Debnath, Snehamoy Majumder

E-ISSN: 2945-0489

Volume 1, 2022

Fig. 1 Schematic diagram of the experimental set up (using twin bluff bodies/baffles)

Fig. 2 Schematic diagram of the diffuser using twin bluff bodies/baffles (not to scale), all dimensions are in mm

International Journal on Applied Physics and Engineering

DOI: 10.37394/232030.2022.1.7

Somnath Bhattacharjee, Arindam Mandal,

Rabin Debnath, Snehamoy Majumder

E-ISSN: 2945-0489

Volume 1, 2022

Fig.3 Photograph of the Experimental Set Up

In figures 1 and 2 the schematic diagrams of an

experimental setup fitted with two bluff bodies and

holes on the inclined surface at different station

distances have been shown. For the case of the

experiment with a single bluff body, the diagrams

are necessary to be modified by replacing the

double bluff body with the single one.

3 Results and Discussion

3.1 Diffuser without Bluff body and

Validation of Results

The experimental results shown in Fig.4 (a and b)

of turbulent air flow through the asymmetric

rectangular diffuser used in the experimental work

have been validated with the published

experimental work of Buice and Eaton, [1].

Recirculation and reattachment of the flow have

been found out inside the diffuser adjacent to the

inclined surface. The velocity distributions are

presented in the two-dimensional coordinate

system in which

-axis is parallel to the inlet

upstream flow and the origin of

- axis is lying at

the onset of diffuser after the constant rectangular

section while the

axis is normal to

- axis. The

centre-line velocity at the inlet is

U14.1

where

is obtained as 12.0 m/s and the corresponding

Reynolds number is calculated using the equation

(2) or Re =1.367×104.

Fig.(a)

International Journal on Applied Physics and Engineering

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Somnath Bhattacharjee, Arindam Mandal,

Rabin Debnath, Snehamoy Majumder

E-ISSN: 2945-0489

Volume 1, 2022

Fig.(b)

Fig. 4 Validation of the current experimental results with the results of Buice and Eaton, [1]

At the station

035.0X

m i.e.











 405.310 b

the velocity profile shows

no sign of the presence of flow separation. In fact,

this is the just outer section of the inlet rectangular

section receiving the incoming flow in the settling

chamber which is 0.083m long. The height of the

settling chamber is 0.015m; therefore, the ratio of

the length of the settling chamber and height for this

section is almost 53.33. It is observed that the

velocity distribution along vertical Axis-Y obtained

from the present experiment agrees very well with

that of Buice and Eaton, [1], experimental work.

The same good agreement has also been observed at

a station distance

09.0X

for











 0.610 b

, but no phenomena of any

recirculation i.e. separation or the reattachment of

the turbulent flow has occurred. This is due to the

fact that the flow is still not facing sufficient adverse

pressure to have a backflow near the wall. But the

presence of a separating flow is clearly observed at

the axial distances

mandmX 30.020.0

respectively

corresponding to

2.204.1310 and

Xb

with

a clear similarity and of the same nature of the back

flows shown by Buice and Eaton, [1]. At a station of

distance

mX 39.0

for

08.2710  b

the

recirculation bubbles disappear showing the

reattachment of the separating flow. The other axial

station distances chosen for the current

experimentation are

mandmmmX 90.080.0,70.0,60.0

respectively with

the corresponding non-dimensional values of

6033.53,67.46,4020 and

Xb

respectively.

In all of the above cases the current results agree

well with the experimental results of Buice and

Eaton, [1].

3.2 Diffuser with Single and Twin Bluff

bodies:

The present investigation provides a complete set of

information in the upstream position, diffuser region

and downstream of the diffuser model of 10°

inclinations. The single bluff body of size 0.20 ×

0.02 × 0.02 m is placed over the bottom horizontal

wall at a distance of 0.18 m from the inlet section of

the diffuser. The inlet condition of the air flow is

turbulent with

=1.367× 104, 1.749× 104 and

1.833× 104 respectively. Measurements have been

taken in the mid-stream plane

XX 

O Buice and Eaton, [1]

Present Experiment

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DOI: 10.37394/232030.2022.1.7

Somnath Bhattacharjee, Arindam Mandal,

Rabin Debnath, Snehamoy Majumder

E-ISSN: 2945-0489

Volume 1, 2022

(a)

(b)

(c)

(d)

Fig. 5 Transverse distribution of Stream wise velocity (for single bluff body)

Figures 5(a) to 5(d) illustrate the distributions of

mean velocities of fluid at different axial station

distances along the

-axis from the inlet cross

section of the diffuser. From the figure 5(a), it has

been observed that no generation of recirculation

occurs before the edge of the bluff body, the

measurements being taken from the lower horizontal

wall of the diffuser towards the upper inclined wall.

As the measurements are conducted in the

downstream direction it has been found that there

exists recirculation of the turbulent flow adjacent to

the inclined surface. The recirculation occurs at a

distance of 0.075 m away from the inlet of the

diffuser and it ends at a distance of 0.535 m away

from the inlet of the diffuser. The effective

recirculation bubble length therefore equals to 0.460

m. Flow separation is generated due to the adverse

pressure gradient of the flow caused by the gradual

expansion of the volume of flow with larger

inclination angle of the diffuser.

When two bluff bodies of equal size are placed,

measurements have been carried out over the top

surfaces of the bluff bodies at the station distances

of 0.18 m to 0.20 m and 0.30 m to 0.32 m

respectively. Recirculation occurs in the region

between the distances of 0.075 m and 0.535 m away

from the inlet section of the diffuser. Figure 5(d) as

well as 6(f) clearly depicts the occurrence of re-

attachment of the flow in the downstream region of

the diffuser. From figures 5(b) to 5(c) and figures

6(b) to 6(e), it has been observed that recirculation

size is somewhat smaller above the top surface of

the baffles than that in other locations. Recirculation

bubble generated before the second baffle towards

the inlet section is smaller in size than that

generated just after the baffle in the downstream

region inside the diffuser. From the figures 5(a) to

5(d) and 6(a) to 6(f) it is also evident that the axial

mean velocity increases with increase of Reynolds

number.

International Journal on Applied Physics and Engineering

DOI: 10.37394/232030.2022.1.7

Somnath Bhattacharjee, Arindam Mandal,

Rabin Debnath, Snehamoy Majumder

E-ISSN: 2945-0489

Volume 1, 2022

(a)

(b)

(c)

(d)

(e)

(f)

Fig. 6 Transverse distribution of Stream wise velocity (for double bluff bodies)

Lower Wall

Upper Wall

Single Bluff body

(a)

(b)

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DOI: 10.37394/232030.2022.1.7

Somnath Bhattacharjee, Arindam Mandal,

Rabin Debnath, Snehamoy Majumder

E-ISSN: 2945-0489

Volume 1, 2022

Twin Bluff bodies

Fig. 7 Variation of Coefficient of Friction

(d) Upper Wall

Figures 7(a) to 7(d) illustrate the values of

coefficient of skin friction on the lower and upper

walls at different Reynolds numbers for the cases of

single and double bluff bodies respectively. Friction

force increases as the solid surface of the bluff

bodies are introduced disrupting the fluid flow and it

is clearly evident from the figures 7(a) to 7(d). From

the figures 7(a) to 7(d), it is observed that

coefficient of friction decreases with increase of

axial distance measured from the inlet section of the

diffuser and is found negative at the recirculation

zones. Coefficient of skin friction reaches nearly a

constant value at the outlet of the diffuser. It has

been also seen from the figures 7(a) to 7(d),

coefficient of skin friction increases with the

increase of Reynolds number of the turbulent flow

in a diffuser. The curves so obtained are drooping in

nature where the value of coefficient of skin friction

decreases with the increase of station distances.

Single Bluff body

(a)

Twin Bluff bodies

(b)

Fig.8 Variation of Coefficient of friction with Re

Figures 8(a) and 8(b) show the variation of

coefficient of skin friction with the increase of

Reynolds numbers for the cases of single and twin

bluff bodies respectively. The current experimental

value of the coefficient of friction correlates as the

function of Reynolds number and the relevant

correlations achieved for upper wall as well as lower

wall of the diffuser are given in Table1. These

correlations are valid for Re=1.367 × 104, 1.749

×104 and 1.833 × 104. Table 1

Lower Wall

Upper Wall

Single

Bluff

Body

213

101Re102

Re106









002.0Re103

Re101

211







Twin

Bluff

Bodies

Re109

Re102

212







001.0Re102

Re108

212







International Journal on Applied Physics and Engineering

DOI: 10.37394/232030.2022.1.7

Somnath Bhattacharjee, Arindam Mandal,

Rabin Debnath, Snehamoy Majumder

E-ISSN: 2945-0489

Volume 1, 2022

3.3 Uncertainty of experimental results

Uncertainty has been calculated for the fluid flow

parameters measured as (i) for Reynolds number =

3.3% to 3.4% and (ii) for Coefficient of friction =

1.198% to1.67% respectively.

4 Conclusion

The present experimental results are validated with

the benchmark work of Buice and Eaton, [1],

considering the same geometry of diffuser and

boundary conditions of the turbulent flow in an

asymmetric diffuser. The current study shows a

good agreement with Buice and Eaton, [1]. This

validation approves the authenticity and accuracy of

the experimental set up designed, developed and

fabricated to measure the turbulent flow parameters

through a rectangular diffuser. The matching of the

velocity distribution also confirms the authenticity

of the current experimental methodology.

The present experiment has been aimed to

distinguish the effect of single and double bluff

bodies of identical geometry in shape and size fitted

on the bottom wall of an asymmetrical two

dimensional horizontal diffuser with an inclination

angle of 10° on the turbulent fluid flow. It has been

observed that recirculation zones are generated due

to the presence of the bluff bodies opposite to the

flow direction. Recirculation occurs on the top of

the bluff body for the case of single bluff body.

Thereafter it exists after the bluff body towards the

outlet of the diffuser with larger size. For the case of

twin bluff bodies, recirculation also exists between

the spacing of the two bluff bodies. Coefficient of

skin friction increases with the increase of Reynolds

number. With the increase of axial distance

measured from the inlet section of the diffuser,

coefficient of skin friction decreases and is found to

be negative at the recirculation zones. Coefficient of

skin friction reaches a constant value at the

downstream side of the diffuser. The value of

coefficient of skin friction is lesser in the upper wall

and higher in the lower wall in case of the flow

through the diffuser. Some relevant correlations

have also been established between the coefficient

of skin friction and Reynolds number which is

shown in Table no.1. These correlations are valid

for corresponding Reynolds numbers of 1.367× 104,

1.749×104 and 1.833× 104 respectively.

The significant use of the bluff bodies of different

sizes at different spacing and orientations inside the

diffuser duly validated with the results of Buice and

Eaton, [1], makes it possible to optimize the length

of the diffuser and it economises the industrial use

of the diffuser.

Acknowledgment:

The authors express their sincere thanks and

gratitude to all who have extended their helping

hands by giving valuable suggestions and technical

support for this experimental work done at

Hydraulics Laboratory, Mechanical Engineering

Department, Jadavpur University, Kolkata (India).

Nomenclature

Coefficient of Skin friction

Inlet height of the diffuser, m

Velocity gradient of the upper and

lower wall of the diffuser

Reynolds number

X, x, S

The distance of the station

measured from the inlet end of the

diffuser, m

Bulk average velocity, m/s

Velocity at certain location and

height, m/s

avg

Average Velocity of Fluid, m/s

p

Difference of Stagnation and Static

pressure, Pa

Density of air, kg/m3

Co-efficient Dynamic viscosity of

fluid at room temperature, Pa-s

References:

[1] Buice, C. U. and Eaton, J. K., Experimental

Investigation of Flow through an

Asymmetric Plane Diffuser, Journal of

Fluids Engineering, Vol. 122, 2000, pp.

433-435.

[2] Obi, S., Aoki, K. and Masuda, S.,

Experimental and Computational Study of

Turbulent Separating Flow in an

Asymmetric Planar Diffuser, In:

Proceedings of the 9th Symposium on

Turbulent Shear Flows, Kyoto, Japan, Vol.

305, 1993, pp. 1-4.

[3] Obi, S., Ohizumi, K., Aoki, K. and

Masuda, S., Turbulent Separation Control

in a Plane Asymmetric Diffuser by Periodic

Perturbation, Elsevier Science, 1993, pp.

633-642.

International Journal on Applied Physics and Engineering

DOI: 10.37394/232030.2022.1.7

Somnath Bhattacharjee, Arindam Mandal,

Rabin Debnath, Snehamoy Majumder

E-ISSN: 2945-0489

Volume 1, 2022

[4] Gullman-Strand, J., Törnblom, O.,

Lindgren, B., Amberg, G. and Johansson,

A. V., Numerical and experimental study

of separated flow in a plane asymmetric

diffuser, International Journal of Heat and

Fluid Flow, Vol.25, 2004, pp. 451-460.

[5] Okwuobi, P. A. C. and Azad, R. S.,

Turbulence in a conical diffuser with fully

developed flow at entry, Journal of Fluid

Mechanics, Vol. 57, 1973, pp. 603- 622.

[6] Azad, R.S. and Kassab, S. Z., Turbulent

flow in a conical diffuser: overview and

implications, Physics of Fluids, Vol. A1:

1989, pp. 564-573.

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International Journal on Applied Physics and Engineering

DOI: 10.37394/232030.2022.1.7

Somnath Bhattacharjee, Arindam Mandal,

Rabin Debnath, Snehamoy Majumder

E-ISSN: 2945-0489

Volume 1, 2022

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IN RECTANGULAR CHANNEL WITH

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Vol.32, No.2, April 2009, pp. 131-143.

Authors’ Contributions:

Dr. Somnath Bhattaharjee, Dr. Arindam Mandal and

Dr. Rabin Debnath have conducted research and

performed the experimental process including

validation. Dr. Somnath Bhattacharjee (the

corresponding author) has developed the

methodology and prepared the initial draft as well as

edited subsequently. Prof. (Dr.) Snehamoy

Majumder has coordinated the execution of the

research work with his immense depth of

knowledge and mentorship. His discretionary power

and editing capability make the research work more

enriched with scientific innovation.

Sources of funding for research

presented in a scientific article or

scientific article itself

No specific financial support for research is

received to carry out this experimental study.

Creative Commons Attribution License 4.0

(Attribution 4.0 International, CC BY 4.0)

This article is published under the terms of the Creative

Commons Attribution License 4.0

https://creativecommons.org/licenses/by/4.0/deed.en_US

International Journal on Applied Physics and Engineering

DOI: 10.37394/232030.2022.1.7

Somnath Bhattacharjee, Arindam Mandal,

Rabin Debnath, Snehamoy Majumder

E-ISSN: 2945-0489

Volume 1, 2022