Final Project - MSc in Automotive Engineering Tiago...
Transcript of Final Project - MSc in Automotive Engineering Tiago...
Final Project - MSc in Automotive Engineering
Tiago Carvalho
Technological evolution in the past years led to a higher energy consumption
A higher energy consumption led to a larger environmental pollution and consumption of natural resources
The contribution of Transports towards the total final energy consumption in the EU reached a
value of 31.7% in 2010
Governments applied laws and regulations to reduce the pollution emissions derived from
vehicles
The automotive industry has been increasing the investment on research & development of new solutions for the reduction of fuel consumption
and pollutant emissions
INTERREG’s CEREEV Project investigates the concepts of IC engines in order to improve the efficiency of a small hybrid electric vehicle
Studied possibility of using a split-cycle engine with hybrid vehicle
How to improve air intake in a rapid charge engine?
Injection of air in combustion chamber
CEREEV engine: 80mm diameter and 500rpm
Injection of air in cross-flow of air:
1
2 1 – Cross-flow
2 – Injection flow
Duct Injector
Theoretical calculations of hydrodynamic entrance region inside the duct:
Lh > ~ 2500mm
Hydrodynamic entrance length is bigger than wind tunnel working section
Duct used:
◦ Rectangular profile
◦ Metal and polypropylene sections
◦ Straighteners located at the metal section’s entrance
Results at 430rpm wind tunnel fan speed:
-80
-60
-40
-20
0
20
40
60
0 2 4 6 8 10 12 14
Vert
ical p
osit
ion in d
uct
(mm
)
Cross-flow velocity - U component (m/s)
Velocity profile at duct's exit - Comparison Pitot tube vs. PIV
PIV - End of duct Pitot tube - Entrance of duct
Pitot tube - Middle of duct Pitot tube - End of duct
Static injection at different ASOI with 4bar injection
ASOI = Advance Start Of Injection (relative to the first PIV laser pulse)
Injector
Results at 4bar and -500μs ASOI:
Injector
Vertical penetration
Angle of injection
CVP Formation
Experiment was done with 4 different ASOI and 4 different cross-flow speeds
Images were post-processed using the Adaptive PIV method
Vector field results:
Display options were altered to observe the alterations in the U and V components of the flow’s velocity
The U (horizontal) component is displayed with a contour plot. The V (vertical) component is displayed with vertical blue vectors
Contour plot results:
Vector fields obtained at -500μs:
2m/s 5m/s 7m/s 10m/s
Contour plots obtained at -500μs:
2m/s 5m/s 7m/s 10m/s
The results obtained at -500μs:
Cross-flow speed
Static 2m/s 5m/s 7m/s 10m/s
Vertical penetration
(mm) 19 16 13 11 11
Speed of injection (m/s) 18 21 22 22 23
Angle of injection (o) 42 44 49 54 55
Cross-flow speed
2m/s 5m/s 7m/s 10m/s
Max |U| (m/s) 36 41 45 44
Max |V| (m/s) 38 47 36 39
Purpose of experiment was to investigate the injection of air into combustion chamber of a rapid charge IC engine
Model consisted of injecting compressed nitrogen in a duct with a cross-flow of air. PIV optical technique was used to analyse the results
The results showed: ◦ CVP are formed with the injection of compressed
nitrogen in air
◦ Increase in the cross-flow speed affects the profile of the injection
Increasing the cross-flow speed will:
Increase Decrease Maintain
Angle of injection (horizontal penetration)
Injection’s vertical penetration
Maximum V component of the flow
Maximum U component of the flow
CVP formation and intensity
1. Use compressed air instead of nitrogen
2. Different seeding process through the injector
3. Variable pressure instead of constant
4. Study injector’s internal dimensions and determine mass flow injected
5. Impact of different injection angles
6. 3D optical method for analysing the entire injection’s hollow cone
7. CFD analysis and in-cylinder experimentation
THANK YOU