This document discusses laser ignition systems (LIS) as an alternative to conventional spark plug ignition systems in internal combustion engines. It begins with an introduction describing the need to improve engine efficiency and reduce emissions. It then describes the processes of conventional spark ignition and the disadvantages it poses. The document proceeds to explain the laser ignition process, including the mechanisms of non-resonant breakdown and working. It discusses the advantages of LIS over spark plugs and experimental results showing reduced emissions and fuel consumption. It concludes that LIS has potential to enable leaner combustion but costs remain high.
Laser ignition is an alternative method for igniting compressed gaseous mixture of fuel and air. The method is based on laser devices that produce short but powerful flashes regardless of the pressure in the combustion chamber
PAAVAI COLLEGE OF ENGINEERING / Department of Automobile Engineering / presented by ARAVIND KUMAR M S (622014102001),
SANTHOSH KUMAR B (622014102325) &
DEEPAKKUMAR N (622014102701)
Internal combustion engines play a dominant role in transportation and energy production.
In technical appliances such as internal combustion engines, reliable ignition is necessary for adequate system performance.
Unfortunately, conventional spark plug ignition shows a major disadvantage with modern spray-guided combustion processes since the ignition location cannot be chosen optimally.
A laser ignition source has the potential of improving engine combustion with respect to conventional spark plugs.
Laser ignition is an alternative method for igniting compressed gaseous mixture of fuel and air. The method is based on laser devices that produce short but powerful flashes regardless of the pressure in the combustion chamber
PAAVAI COLLEGE OF ENGINEERING / Department of Automobile Engineering / presented by ARAVIND KUMAR M S (622014102001),
SANTHOSH KUMAR B (622014102325) &
DEEPAKKUMAR N (622014102701)
Internal combustion engines play a dominant role in transportation and energy production.
In technical appliances such as internal combustion engines, reliable ignition is necessary for adequate system performance.
Unfortunately, conventional spark plug ignition shows a major disadvantage with modern spray-guided combustion processes since the ignition location cannot be chosen optimally.
A laser ignition source has the potential of improving engine combustion with respect to conventional spark plugs.
Since the conventional Battery Ignition System has many drawbacks so, this Laser Ignition System is helpful in improving the efficiency of the engine as well it helps to reduce the emission from the engine.
NANO…one billionth of one and one third of micro, to be precise 10^-9m. Nanotechnology is much discussed these days as an emerging frontier – a realm in which machines operate at scales of billionth a meter. It is actually a multitude of rapidly emerging technologies based upon the scaling down of existing technologies to the next level of precision and miniaturization. In the field of nano technologies researchers are enthusiastic about its potential applications in fields such as energy, medicine, electronics, computing and materials. Of late, one of the emerging aspects dealing Nanotechnology in mechanical field is the internal combustion engine on a nano scale, which we have chosen as our area of interest. Heat engines have evolved from external combustion engines to internal combustion engines and the hot off the block is the nano internal combustion engine.
"Study of Laser Ignition System" / PAAVAI COLLEGE OF ENGINEERING / B.E- AUTOMOBILE ENGINEERING / final year project presented by ARAVIND KUMAR M S (622014102001),SANTHOSH KUMAR B (622014102325) &
DEEPAKKUMAR N (622014102701)
Cast iron is extensively used as the material for manufacturing disc brakes. This is much heavier and thus reduces initial acceleration and causes more fuel consumption. For reducing these effects, we use ceramic brakes.
This engine is constructed in such a way that it can produce higher efficiency by emitting zero emission of harmful gases,because of complete burning of fuel.It is light,small and of low cost.It is benificial for the environment.It can solve the problems of over consumption of fuel.It creates a revolution in the field of engine mechanism.It has two strokes more than the four stroke engine.In future it may be used in every technical field due to higher output and low pollution factor.
Since the conventional Battery Ignition System has many drawbacks so, this Laser Ignition System is helpful in improving the efficiency of the engine as well it helps to reduce the emission from the engine.
NANO…one billionth of one and one third of micro, to be precise 10^-9m. Nanotechnology is much discussed these days as an emerging frontier – a realm in which machines operate at scales of billionth a meter. It is actually a multitude of rapidly emerging technologies based upon the scaling down of existing technologies to the next level of precision and miniaturization. In the field of nano technologies researchers are enthusiastic about its potential applications in fields such as energy, medicine, electronics, computing and materials. Of late, one of the emerging aspects dealing Nanotechnology in mechanical field is the internal combustion engine on a nano scale, which we have chosen as our area of interest. Heat engines have evolved from external combustion engines to internal combustion engines and the hot off the block is the nano internal combustion engine.
"Study of Laser Ignition System" / PAAVAI COLLEGE OF ENGINEERING / B.E- AUTOMOBILE ENGINEERING / final year project presented by ARAVIND KUMAR M S (622014102001),SANTHOSH KUMAR B (622014102325) &
DEEPAKKUMAR N (622014102701)
Cast iron is extensively used as the material for manufacturing disc brakes. This is much heavier and thus reduces initial acceleration and causes more fuel consumption. For reducing these effects, we use ceramic brakes.
This engine is constructed in such a way that it can produce higher efficiency by emitting zero emission of harmful gases,because of complete burning of fuel.It is light,small and of low cost.It is benificial for the environment.It can solve the problems of over consumption of fuel.It creates a revolution in the field of engine mechanism.It has two strokes more than the four stroke engine.In future it may be used in every technical field due to higher output and low pollution factor.
A comparitive study of laser ignition and spark ignition with gasoline air m...Amiya K. Sahoo
With the advent of lasers in the 1960s, researcher and engineers discovered a new and powerful tool to investigate natural phenomena and improve technologically critical processes. Due to recent progress in the area of high power fiber optics allowed convenient shielding and transmission of the laser light from one part of engine to the combustion chamber.
Laser is emerging as a strong concept for alternative ignition in spark ignition engine. Laser ignition has potential advantages over conventional spark plug ignition. Laser ignition system is free from spark electrodes hence there is no loss of spark energy to the electrodes, which are also free from erosion effect. In addition the potential advantages of the lasers lies in its flexibility to change the ignition location. Also, multiple ignition points can be achieved rather comfortably as compared to conventional electric ignition systems using spark plugs, And many more.
In this paper, advantages and disadvantages of laser and conventional spark ignition systems in the context of combustion engines are discussed, and performances of laser ignition and conventional spark ignition systems are comparatively evaluated in terms of Minimum Ignition Energy, Ignition Probability and Exhaust Emissions at similar operating conditions of the engine and graphs are plotted.
And will also explain how laser ignition extends the lean flammability limit, while the spark ignition could be more favorable for rich mixture.
At present, a laser ignition plug is very expensive compared to a standard electrical spark plug ignition system and it is no where near ready for deployment. But the potential and advantages certainly make the laser ignition more attractive in many practical applications
PAAVAI COLLEGE OF ENGINEERING / Department of Automobile Engineering / submitted by ARAVIND KUMAR M S (622014102001),
SANTHOSH KUMAR B (622014102325) &
DEEPAKKUMAR N (622014102701).
Laser ignition is an alternative method for igniting compressed gaseous mixture of fuel and air. The method is based on laser devices that produce short but powerful flashes regardless of the pressure in the combustion chamber
Laser ignition is an alternative method for igniting compressed gaseous mixture of fuel and air. The method is based on laser devices that produce short but powerful flashes regardless of the pressure in the combustion chamber. Usually, high voltage spark plugs are good enough for automotive use, as the typical compression ratio of an otto cycle internal combustion engine is around 10:1 and in some rare cases reach 14:1. However, fuels such as natural gas or methanol can withstand high compression without self ignition. This allows higher compression ratios, because it is economically reasonable, as the fuel efficiency of such engines is high. Using high compression ratio and high pressure requires special spark plugs that are expensive and their electrodes still wear out. Thus, even expensive laser ignition systems could be economical, because they would last longer
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
Learn about the cost savings, reduced environmental impact, and minimal disruption associated with trenchless technology. Discover detailed explanations of popular techniques such as pipe bursting, cured-in-place pipe (CIPP) lining, and directional drilling. Understand how these methods can be applied to various types of infrastructure, from residential plumbing to large-scale municipal systems.
Ideal for homeowners, contractors, engineers, and anyone interested in modern plumbing solutions, this guide provides valuable insights into why trenchless pipe repair is becoming the preferred choice for pipe rehabilitation. Stay informed about the latest advancements and best practices in the field.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
2. INTRODUCTION
• It's widely accepted that the internal combustion engines
will continue to power our vehicles.
• Hence, as the global mobilisation of people and goods
increases, advances in combustion and after-treatment are
needed to reduce the environmental impact of the
continued use of IC engine vehicles.
• To meet environmental legislation requirements,
automotive manufacturers continue to address two critical
aspects of engine performance, fuel economy and exhaust
gas emissions.
• New engines are becoming increasingly complex, with
advanced combustion mechanisms that burn an increasing
variety of fuels to meet future goals on performance, fuel
economy and emissions.
• The spark plug has remained largely unchanged since its
invention, yet its poor ability to ignite highly dilute air-fuel
mixtures limits the potential for improving combustion
efficiency.
3. INTRODUCTION CONTINUED...
• Spark ignition (SI) also restricts engine design,
particularly in new engines, since the spark position is
fixed by the cylinder head location of the plug, and the
protruding electrode disturbs the cylinder geometry and
may quench the combustion flame kernel.
• So, many alternatives are being sought after to counter
these limitations.
• One of the alternative is the laser ignition system (LIS)
being described here.
• Compared to a conventional spark plug, a LIS should be a
favourable ignition source in terms of lean burn
characteristics and system flexibility.
• So, in this paper we'll be discussing the implementation
and impact of LIS on IC engines
4. PROCESSES & MECHANISMS
Spark Ignition System
• When the ignition switch is turned on current flows from the battery to
the ignition coil. Current flows through the Primary winding of the
ignition coil where one end is connected to the contact breaker. A cam
which is directly connected to the camshaft opens and closes the contact
breaker (CB) points according to the number of the cylinders. When the
cam lobe pushes CB switch, the CB point opens which causes the current
from the primary circuit to break.
• Due to a break in the current, an EMF is induced in the second winding
having more number of turns than the primary which increases the
battery 12 volts to 22,000 volts. The high voltage produced by the
secondary winding is then transferred to the distributor. Higher voltage
is then transferred to the spark plug terminal via a high tension cable.
• A voltage difference is generated between the central electrode and
ground electrode of the spark plug. The voltage is continuously
transferred through the central electrode (which is sealed using an
insulator).
• When the voltage exceeds the dielectric of strength of the gases
between the electrodes, the gases are ionized. Due to the ionization of
gases, they become conductors and allows the current to flow through
the gap and the spark is finally produced.
5. Disadvantages of Spark Plug Ignition
• The following are the drawbacks of SI:
1. Location of spark plug is not flexible as it require shielding of
plug from immense heat and fuel spray.
2. It results in high amount of NOx emission .
3. It require frequent maintenance to remove carbon deposits.
4. Leaner mixtures cannot be burned efficiently.
5. Degradation of electrodes at high pressure and temperature
6. Flame propagation is slow.
7. Multi point fuel ignition is not feasible.
8. Higher turbulence levels are required.
To overcome the above mentioned disadvantages LIS is being
sought after.
6. LASER Ignition System
• LI requires certain conditions to be met for two basic steps to take place, spark formation (generally limited by
breakdown intensity) and subsequent ignition (generally limited by a minimum ignition energy or MIE).
• There are four mechanisms by virtue of which LI is able to ignite the air-fuel mixture.
• They are,
1. Thermal initiation (TI)
2. Non-resonant breakdown (NRB)
3. Resonant breakdown (RB)
4. Photo chemical ignition (PCI)
Amongst the above mentioned mechanisms NRB is used the most.
Laser Spark Plug
7. NON RESONANT BREAKDOWN
• In NRB, the focused laser beam creates an electric field of sufficient intensity to cause dielectric breakdown of the air-
fuel mixture.
• The process begins with multi-photon ionisation of few gas molecules which releases electrons that readily absorb
more photons via the inverse bremsstrahlung process to increase their kinetic energy.
• Electrons liberated by this means collide with other molecules and ionise them, leading to an electron avalanche, and
breakdown of the gas.
• Multi-photon absorption processes are usually essential for the initial stage of breakdown because the available photon
energy at visible and near IR wavelengths is much smaller than the ionisation energy.
• For very short pulse duration (few picoseconds) the multi photon processes alone must provide breakdown, since there
is insufficient time for electron-molecule collision to occur.
• Thus this avalanche of electrons and resultant ions collide with each other producing immense heat hence creating
plasma which is sufficiently strong to ignite the fuel.
8. WORKING and MECHANISM
The laser ignition system has a laser transmitter with a fibre-optic cable powered by the car’s
battery. It shoots the laser beam to a focusing lens that would consume a much smaller space
than current spark plugs. The lenses focus the beams into an intense pinpoint of light by passing
through an optical window, and when the fuel is injected into the engine, the laser is fired and
produces enough energy (heat) to ignite the fuel.
9. WORKING and MECHANISM….CONTINUED
The laser beam is passed through a convex lens, this convex
lens converge the beam and make it immensely strong and
sufficient enough to start combustion at that point. Hence
the fuel is ignited, at the focal point, with the mechanism
shown above. The focal point is adjusted where the ignition
is required to have.
• The plasma generated by the Laser beam results in two of
the following actions :
1. Emission of high energy photons
2. Generation of shock waves
The high energy photons, heat and ionise the charge present
in the path of laser beam which can be seen from the
propagation of the flame which propagates longitudinally
along the laser beam.
The shock waves carry energy out wards from the laser beam
and thus help in propagation of flame as shown in the above
figure.
10. Laser Ignition process along time
Laser ignition encompasses the nanosecond domain of the laser pulse itself to the duration of the entire
combustion lasting several hundreds of milliseconds.
The laser energy is deposited in a few nanoseconds which leads to a shock wave generation. In the first
milliseconds an ignition delay can be observed which has duration between 5 – 100 ms depending on the
mixture. Combustion can last between 100 ms up to several seconds again depending on the gas mixture,
initial pressure, pulse energy, plasma size, position of the plasma in the combustion bomb and initial
temperature.
11. ADVANTAGES OF LIS
The following are the advantages of using a LIS:
1. Location of laser is flexible as it does not require shielding from immense heat and fuel spray and
focal point can be made anywhere in the combustion chamber.
2. It does not require maintenance to remove carbon deposits because of the fact that whole
system is isolated.
3. Leaner mixtures can be burned and fuel ignition inside combustion chamber is also possible as
the certainty of fuel presence is very high.
4. High pressure and temperature does not affect the performance allowing the use of high
compression ratios.
5. Flame propagation is fast .
6. Higher turbulence levels are not required due to above said advantages.
12. Engine Experiments and Results
Experiment with laser ignition of the engine has been performed with a q
switched Nd:YAG laser.
The laser beam was focused into the chamber by means of a
lens with a focal length of 50 mm. Variations of pulse energies as well as
fuel mixtures have been performed to judge the feasibility of the
process. Results indicate that ignition-delay times are smaller and
pressure gradients are much steeper compared to conventional spark
plug ignition.
Compared to conventional spark plug ignition, laser ignition
reduces the fuel consumption by several per cents. Exhaust emissions are
reduced by nearly 20%. It is important that the benefits from laser
ignition can be achieved at almost the same engine smoothness level.
Research Engine Setup
15. Self-Cleaning Properties
Another important question with a laser ignition system is its
reliability. It is clear that the operation of an engine causes very
strong pollution within the combustion chamber. Deposits
caused by the combustion process can contaminate the beam
entrance window and the laser ignition system will probably fail.
To quantify the influence of deposits on the laser
ignition system, the engine has been operated with a spark plug
at different load points for more than 20 hours with an installed
beam entrance window.
As can be seen in fig, the window was soiled with a dark layer of
combustion deposits. Afterwards, a cold start of the engine was
simulated. Already the first laser pulse ignited the fuel/air
mixture. Following laser pulses ignited the engine without
misfiring, too. After 100 cycles the engine was stopped and the
window was disassembled. As can be seen from fig, all deposits
have been removed by the laser beam.
Self–Cleaning Properties
16. CONCLUSION
• Research to date on LI in engines has demonstrated improvements in combustion stability. With proper
control, these improvements can enable engines to be run under leaner conditions, with higher Exhaust
Gas Recirculation (EGR) concentrations, or at lower idle speeds without increasing the noise, vibration and
harshness characteristics of a vehicle.
• LI gives significantly shorter power duration compared to SI. With the recent development of higher
average power and higher pulse frequency lasers, it is expected that a multi-strike LI system and associated
combustion control can reduce the probability of misfires under high levels of dilution.
• The prospects for LI are also particularly exciting from a control perspective, from optical sensing of the in-
cylinder combustion, to the array of possible ignition activation and control mechanisms.
• It is anticipated that this, combined with the capability to control the ignition location and timing, will play
a significant role in optimisation of future engines by dynamic feedback control.
• The only limitations of the LIS is it's highly expensive setup.
17. REFERENCES
[1] Bergmann and Schaefer, Lehrbuch der Experimentalphysik: Elektrizit¨at und Magnetism us, vol. 2, Walter de Gruyter Berlin, 1981.
[2] D. R. Lidde, ed., CRC Handbook of Chemistry and Physics, CRC Press, 2000
[3] J. Ma, D. Alexander, and D. Poulain, “Laser spark ignition and combustion Characteristics of methane-air mixtures,” Combustion and Flame
112 (4), pp. 492–506, 1998
[4] J. Syage, E. Fournier, R. Rianda, and R. Cohn, “Dynamics of flame propagation
Using laser-induced spark initiation: Ignition energy measurements,” Journal of Applied Physics 64 (3), pp. 1499–1507, 1988.
[5] Lambda Physik, Manual for the LPX205 Excimer Laser, 1991
[6] M. Gower, “Krf laser-induced breakdown of gases,” Opt. Commun. 36, No. 1, pp. 43–45, 1981.
[7] M. Lavid, A. Poulos, and S. Gulati, “Infrared multiphoton ignition and Combustion enhancement of natural gas,” in SPIE Proc.: Laser
Applications in Combustion and Combustion Diagnostics, 1862, pp. 33–44, 1993.
[8] P. Ronney, “Laser versus conventional ignition of flames,” Opt. Eng. 33 (2), pp. 510–521, 1994.
[9] R. Hill, “Ignition-delay times in laser initiated combustion,” Applied Optics. 20 (13), pp. 2239–2242, 1981.
[10] T. Huges, Plasma and laser light, Adam Hilg