Presentation on PhD research work

1. Ravish Vinze
PhD Mechanical Engineering

2. OUTLINE OFTHE PRESENTATION
 Educational and Professional Background
 Summery of research during PhD
 Applications of Jet Impingement
 Experimental setup, procedure and validation
 Important outcomes
 Key Results
 List of publication

3. EDUCATIONAL BACKGROUND
 Doctor of Philosophy (July2012- April2017)
Specialization –Thermal Engineering
Title – “Local heat transfer distribution by impinging incompressible and compressible jets”
Institute – Defence Institute of AdvancedTechnology (DU), Pune
Result- 72.89% (Course work)
 Master ofTechnology (Aug2008-Nov2010)
Specialization –Thermal Engineering
Title – “Simulation of Gravity Driven Water Pool of AHWR using Fluent And CATHARE ”
Result- 8.01/10
Institute – Maulana Azad National Institute of Technology, Bhopal
 Bachelor of Engineering (Aug2004- June2008)
Specialization – Mechanical Engineering
Result- 67.97%
Institute – H.C.E.T. Jabalpur, R.G.P.V. Bhopal

4. PROFESSIONAL BACKGROUND
 Research Engineer -3 (Nov2016 – Present)
Company – Saint Gobain Research Indi,
Chennai,TN
Department - HABITAT
Work – Development of experimental test setup
for evaluating product's thermal performance
 Project Associate (July2016 – Nov 2016)
Company – IIT Bombay, Under Prof. S.V.
Prabhu,Mechanical Engineering
Lab – FMFP, Mechanical Engineering
Work -Carried out experimental research on
"Heat transfer investigations of dimpled surfaces
impinged by air jets" sponsored by GTRE Bangalore
 During PhD academic responsibilities
(2012-2016) – To teach Heat transfer and
Thermodynamics to students ofTank Technology
courses (Army Personals)
 Assistant Professor (Aug2011- June2012)
Institute –TITECH Jabalpur,M.P.
Department – Mechanical Engineering
Subjects - Thermodynamics, Heat transfer,
Automobile Engineering
 Award- Researcher of The Year -2017,
Defence Institute of Advanced Technology

5. SUMMERY OF RESEARCH DURING PHD
 Objective - To study impinging circular jets characteristics for heat transfer by varying of jet
temperature , nozzle profile, Reynolds number and Nozzle pressure ratios using Thin foil
heater technique with IR Camera and Shadowgraph techniques
 Motivation - The purpose of choosing above objectives is to understand single circular jet
behavior and apply this knowledge for the application of gas turbine badge cooling
 Following are the some important points of research-
 Studied the effect of the heated circular air jets (Tj = 50°C to 175°C) on the local heat transfer
distribution Reynolds numbers ranging from 5000 to 23000
 Examined the effect of Nozzle pressure ratios (NPR) on heat transfer and flow physics for
underexpanded jets
 Studied heat transfer over modified surface for different dimple pitch, dimple depth for dimpled surface
over different Reynolds number

6. APPLICATIONS OF JET IMPINGEMENT
Cooling arrangements of modern gas turbine
blade
Schematics of the flow field due for jet
impingement on wedge deflector
 Han J-C., Dutta S. and Ekkad S. V., “Gas turbine heat transfer and cooling technology”, Taylor and Francis (2012)
 Prahlad T. S., "Some aerodynamic problems of satellite launch vehicles", Sadhana (1987), Vol.10, Parts 3 and 4, 459-495
jet impingement on wedge deflector
 Gas turbine blade cooling
 Combustion chamber wall cooling
 Cooling of electronic components
 Jet deflector
 Cooling or preheating of glass and Steel billets
 Water or abrasive jet machining
 Gas welding or gas cutting

7. EXPERIMENTAL SETUP AND PROCEDURE
Layout of experimental set-up
(1) Air filter (2) Air compressor (3) Air receiver (4) Needle valves (5) Air filter (6) Pressure regulator (7)
Orifice (8) Differential manometer (9) Air Heater (10) Mixing chamber (11) Thermocouples (12)
Insulation (13) Nozzle (14) Impingement assembly (15) Traverse system (16) Infra red camera. (17)
Computer

8. PROCEDURE AND DATA REDUCTION
 Total convective heat transfer:
 Total heat loss due to natural convection and radiation:
 Total heat supplied:
V= Supply voltage (V);
I = Supply current (Amp)
 Heat transfer coefficient :
Tw =Wall temperature (K);
Taw = Adiabatic wall temperature (K)
lossjouleconv qqq 
nat)b(rad)f(radloss qqqq 
VIq joule 
aww
conv
TT
q
h


Heat loss estimation from test plate
Front side
Back side
Radiation and natural convection
losses
Radiation losses
Test plate
A σ εb(Twb
4
- T∞
4
) + hA(Twb- T∞))
A σ εf(Twb
4
- T∞
4
)

9. PROCEDURE AND DATA REDUCTION
 Nusselt number:
Where: k =Thermal conductivity of air (W/m.K)
 Recovery factor:
;Td = Jet dynamic temperature
The recovery factor is influenced by the dynamic temperature which
shows kinetic energy conversion into thermal energy due to the viscous
heating
 
d
jaw
T
TT
R


2
2
2
2
1
1
2
1
2
M
M
C
v
T
p
e
d



 




 



k
hd
Nu 
Ta
w
The typical uncertainties the measurement of wall temperature, heat transfer coefficient, Nusselt number, recovery factor and static pressure
drop measurements are around 3%, 6.5%, 8.8%, 3.5% and 2.3%, as evaluated by a method suggested by Moffat (1988).

10. IMPACT OF NOZZLE PRESSURE RATION
 The length of shock cell depends upon
NPR
 For higher NPR at lower nozzle to plate
distances (z/d ≤ 2) the jet impinges
before formation of shock cell
 For higher nozzle to plate distances (z/d
≥4) the shocks are absent
z/d NPR = 2.4 NPR = 3.75 NPR = 5.10
1
2
4
Shadowgraphs for impinging jets at different NPR for nozzle of 8.37mm
diameter
Setup to capture shadowgraphs
(1) Camera (2) Light Rays (3) Traverse system (4) Nozzle (5) Lenses
(6) Light Source (7) Impingement plate (8) Table.

11. LOCAL NUSSELT NUMBER AND RECOVERY
FACTOR
At z/d = 2
At z/d = 6

12. Schematic layout of jet impingement arrangement
Orifice plate
Dimpled plate
Cold air jets
Spent air
(d)
(t)
MULTIPLE JET IMPINGENT ON DIMPLED SURFACE
 Heat transfer over the flat plate, and dimpled
surface (dimple depth t/d = 0.25 and 0.5 ) for
Reynolds number of 5000 to 40000 is measured
 Effect of jet orifice pitch and dimple pitch (p = 3d,
4d and 5d) on the local and average heat transfer
investigated for nozzle to plate distance of 1d to
6d
 Optimized orifice and dimple pitch configuration
by measuring coefficient of variance (COV) and
effective cooling parameter for all configurations
a. Impinging setup
1. Air filter 2. Pressure vessel 3. Pressure Gauge 4. Gate valve 5. Pressure Regulator 6. Venturi
meter 7. Gate valve 8. Flange 9. Rods 10. Plenum chamber 11. Jet plate 12. Impingement plate
13. Dimpled surface 14. IR Camera 15. Computer
b. Test plates used in present study
Experimental Setup
Pitch = 2d Pitch = 3d Pitch = 4d
Pitch = 4d Pitch = 5dPitch = 3dPitch = 2d
Orientation of orifice plate and test plate
Test plate
(E')
X = 0
X = +1
X = -1
Y = +1Y = 0Y = -1
Position
of orifice
Position
of dimples
Orifice plate
p'
p

13. KEY RESULTS
Average Nusselt number Coefficient of
variance
Effective cooling
parameter
Average Nusselt number: over ±p area
'm' is the number of elements counted in
±p area.
Coefficient of variance:
Effective cooling parameter:
*For Reynolds number 5000 to 40000

14. LIST OF PUBLICATION
International journal publication: (9no.)
 Ravish Vinze, S. Chandel, M.D. Limaye and S.V. Prabhu, “Influence of jet temperature and nozzle shape on the heat transfer distribution
between a smooth plate and impinging air jets”, International Journal of Thermal Sciences, Vol. 99 (2016), 136-151
 Ravish Vinze, S. Chandel, M.D. Limaye and S.V. Prabhu, “Local heat transfer distribution between smooth flat surface and impinging
incompressible air jet from a chevron nozzle”. Experimental Thermal and Fluid Science, Vol. 78 (2016), pp.124–136
 Ravish Vinze, S. Chandel, M.D. Limaye and S.V. Prabhu, “Effect of compressibility and nozzle configuration on heat transfer by impinging air
jet over a smooth plate” Applied thermal engineering, Vol. 101 (2016), pp. 293–307
 Ravish Vinze, S. Chandel, M.D. Limaye and S.V. Prabhu, “Effect of nozzle pressure ratio and nozzle diameter on the heat transfer of a flat
plate impinged by an underexpanded jet”. Applied thermal Engineering (2017),Vol. 115, pp.41–52
 Ravish Vinze, M.D. Limaye , and S.V. Prabhu “Influence of the elliptical and circular orifices on the local heat transfer distribution of a flat
plate impinged by under-expanded sonic jets". Heat and Mass Transfer (2016), pp. 1-16
 Ravish Vinze, Alex Chollackal,, M.D. Limaye and S.V. Prabhu, “Heat transfer characteristics of the jet deflector due to supersonic jet
impingement”. Experimental Thermal and Fluid Science, Vol. 78 (2016), pp.124–136
 Ravish Vinze, Aniket Khade, Pramod Kuntikana, M. Ravitej, Batchu Suresh,V. Kesavan and S.V. Prabhu, "Effect of dimple pitch and depth on
jet impingement heat transfer over dimpled surface impinged by multiple jets" International journal of thermal sciences, 2019, Volume 145,
November 2019, 105974
 Under review – 3 papers
International Conference Proceeding: Four papers presented in international conferences

15. Thank you..