The document discusses the stages of combustion in compression ignition (CI) engines. It describes the four stages as: 1) ignition delay period, 2) rapid combustion period, 3) controlled combustion period, and 4) after-burning period. It also discusses factors that affect the ignition delay period such as compression ratio, engine speed, fuel properties, and intake conditions. The document covers knocking in CI engines and the different types of combustion chambers used.
This presentation was prepared by Mechanical Engineering professor Dr. Shahid Imran during their lecture with final year in their Internal Combustion Engine program offered at University of Engineering and Technology Lahore.
This presentation was prepared by Mechanical Engineering professor Dr. Shahid Imran during their lecture with final year in their Internal Combustion Engine program offered at University of Engineering and Technology Lahore.
Thermo Structural Analysis on Cylinder Head of 4 Stroke VCR Diesel EngineDr. Amarjeet Singh
The main aim of the project is to analyse the design performance of VCR 4 stroke Diesel engine cylinder head at the compression ratio 16.5 using Ansys software. The basic modelling is done on CATIA V5 software. The design exposition can be done structurally and thermally in ansys. By the structural analysis the maximum and minimum von misses stress, total deformation can be determined, the maximum gas pressure required for this analysis is taken from the experimental set up of VCR engine. With the steady state thermal analysis we will get the maximum temperature distribution and total heat flux of the cylinder head with the initial pressure value. The results of both the expositions are used to decide the critical areas of the cylinder head which require further amendment and also the quality of design. If the maximum stress is less than the material strength of the cylinder head then the basic design criteria can be achieved.
Thermo Structural Analysis on Cylinder Head of 4 Stroke VCR Diesel EngineDr. Amarjeet Singh
The main aim of the project is to analyse the design performance of VCR 4 stroke Diesel engine cylinder head at the compression ratio 16.5 using Ansys software. The basic modelling is done on CATIA V5 software. The design exposition can be done structurally and thermally in ansys. By the structural analysis the maximum and minimum von misses stress, total deformation can be determined, the maximum gas pressure required for this analysis is taken from the experimental set up of VCR engine. With the steady state thermal analysis we will get the maximum temperature distribution and total heat flux of the cylinder head with the initial pressure value. The results of both the expositions are used to decide the critical areas of the cylinder head which require further amendment and also the quality of design. If the maximum stress is less than the material strength of the cylinder head then the basic design criteria can be achieved.
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.
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.
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.
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.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
2. I C ENGINES - II
Stages/ Phases Of Combustion
• Combustion in CI Engines
- Stages/ Phases of combustion
1. Ignition delay period ;
Physical delay and chemical delay
2. Rapid combustion period / rapid pressure rise
3. Controlled combustion period /
mechanically controlled period
4. After-Burning period
3. I C ENGINES - II
Air Motion & Combustion
• Combustion in CI Engines
4. I C ENGINES - II
Air Motion & Combustion
Stages/ Phases of combustion
1. Ignition delay period ;
-Preparatory phase:some fuel admitted,not ignited
-Period : start of injection to start of combustion
(p-t curve separates from motoring curve)
-Important : combustion, design, performance,
emissions
-Fuel does not ignite immediately and total delay
period can be explained as; Physical delay and
Chemical delay. Details are shown in the figure.
5. I C ENGINES - II
Air Motion & Combustion
• Combustion in CI Engines : Ignition Delay
6. I C ENGINES - II
Air Motion & Combustion
Stages/ Phases of combustion
Physical delay :
- period ; from beginning of injection to attainment
of chemical reactions.
- process; atomization, vaporization, mixing of fuel
& air, raising to self-ignition temperature
- depends on; fuel,air motion,combustion chamber
7. I C ENGINES - II
Air Motion & Combustion
Stages/ Phases of combustion
Chemical delay :
- Period ; from beginning of chemical reactions to
auto-ignition
- process ; pre-reactions in the mixture taking place
up to auto-ignition that occurs at a local
excess-air factor of 0.5 < λ < 0.7
-depends ; chemical reactions are faster at higher
temperature of the surroundings and accordingly
the chemical delay becomes shorter.
8. I C ENGINES - II
Air Motion & Combustion
Stages/ Phases of combustion
2. Rapid combustion period / rapid pressure rise
- period ; from end of delay or beginning of
combustion to the point of maximum pressure on
indicator diagram
-process ; most of the fuel would have formed
combustible mixture with air and preflame reactions
9. I C ENGINES - II
Air Motion & Combustion
Stages/ Phases of combustion
- depends ;
It may be noted that the maximum pressure
reached during this phase depends upon the delay
period. Longer the delay the higher is the rate of
pressure rise as more fuel gets accumulated
during the delay period.
10. I C ENGINES - II
Air Motion & Combustion
- Stages/ Phases of combustion
3. Controlled combustion period / mechanically
controlled period
-process ; This is the second phase of fuel injection
- period ; from the point of maximum pressure to
thepoint of maximum cycle temperature.
11. I C ENGINES - II
Air Motion & Combustion
-depends ; crank-angle duration of fuel injection as
per load requirements (higher and full load power
out-put ).
-Therefore, this is mechanically controlled by the
injection pump out put characteristics.
12. I C ENGINES - II
Air Motion & Combustion
4. After-Burning period : fuel with the air
- Combustion does not cease with completion of fuel
injection.The unburnt and partially burnt fuel particles
start burning as soon as they come in contact with
oxygen. This continue for a certain duration called
after- burning period.
- period ; starts from the point of max.cycle temp. and
continue over the part of expansion process.
- depends ; rate of after burning depends upon velocity
of diffusion and turbulent mixing of unburnt and
partially burnt fuel with the air
14. I C ENGINES - II
Air Motion & Combustion
• Factors Affecting the Delay Period :
Many design and Operating factors affect the delay
period. Some of the significant factors are;
- Compression ratio
- Engine speed
- Output
- Atomization of fuel and duration of injection
- Injection timing
- Quality of fuel
- Intake temperature and pressure
15. I C ENGINES - II
Air Motion & Combustion
• Factors Affecting the Delay Period :
- Compression ratio (CR )
The effect of CR on compression temperature of air
and the minimum auto ignition temperature of fuel
at the end of compression is shown below
16. I C ENGINES - II
Air Motion & Combustion
• Factors Affecting the Delay Period :
- Engine speed :
The effect of engine speed on ID ( time ) is shown
below
17. I C ENGINES - II
Air Motion & Combustion
• Factors Affecting the Delay Period :
- Output :
With increase load or output, the amount of fuel
injected ( at constant rpm ) increases and therefore
the air-fuel decreases and results in increase in
temperature thereby reducing delay period.
18. I C ENGINES - II
Air Motion & Combustion
• Factors Affecting the Delay Period :
-Atomization of fuel and duration of injection :
Higher fuel-injection press. increases the degree
(fineness) of atomization which reduces ignition
delay due to higher surface to volume ratio.
-Smaller droplets have low depth of penetration due
to less momentum. Such droplets have less velocity
relative to air and shorter fuel spray path, where it
has to find oxygen after vaporization affecting air
utilization factor. Also the aggregate area of
inflammation after ignition will increase resulting in
19. I C ENGINES - II
Air Motion & Combustion
• Factors Affecting the Delay Period :
- Injection timing :
The effect of injection advance timings ( 9º,18º,27º )
for constant injected quantity of fuel on cylinder
pressure is shown below :
20. I C ENGINES - II
Air Motion & Combustion
• Factors Affecting the Delay Period :
-As pressure and temperature at the begning of
injection are lower for higher injection advance, the
delay period increases with increase in injection
advance.
-The optimum angle of advance depends on many
factors. Generally it is about 20º bTDC.
21. I C ENGINES - II
Air Motion & Combustion
• Factors Affecting the Delay Period :
-Quality of fuel
Self ignition temperature is the most important
property of fuel which affects the delay period. A
lower self-ignition temperature results in lower
delay period.
-Fuels with higher cetane number give lower delay.
Other properties of fuel which affect delay period
include volatility, latent heat, viscosity and surface
tension.
22. I C ENGINES - II
Air Motion & Combustion
• Factors Affecting the Delay Period :
-Intake temperature and pressure :
Increase in intake temp. increases compressed air
temp. resulting in reduced delay period. Preheating
may not be desirable as it reduces density of air
affecting volumetric efficiency and power.
-Increase in intake pressure reduces the auto -
ignition temp. and hence the delay period. The peak
pressure will be higher as compression pressure
will be higher with higher intake pressure.
26. I C ENGINES - II
Air Motion & Combustion
• Knock in CI Engines :
-Fuel Injection takes definite interval
- Injection & Combustion take place simultaneously
-Initial droplets while undergoing ignition delay, additional
droplets are being injected
- If ignition delay of fuel is short,
initial few droplets will commence
actual burning
- As a result, mass rate of mixture
burned produce rate of press. rise
for soother combustion as shown
27. I C ENGINES - II
Air Motion & Combustion
• Knock in CI Engines :
- As ignition delay is longer , the actual burning of
first few droplets is delayed and accumulation of
greater quantity of fuel take place. When actual
burning take place under such conditions the rate of
pressure rise increases as shown in fig.
28. I C ENGINES - II
Air Motion & Combustion
• Knock in CI Engines :
- If ignition delay is quite large and the actual
burning is substantially delayed and the
accumulation of fuel is high when actual burning
take place the rate of pressure rise is almost
instantaneous the knocking begins as shown in fig.
29. I C ENGINES - II
Air Motion & Combustion
• Knock in CI Engines :
-Knocking is characterized by extreme pressure
differentials and violent gas vibrations evidenced by
audible knock.
-In CI engines knocking occurs in the beginning of
combustion.
-In order to decrease knocking the actual burning
should start as early as possible after the fuel
injection begins.
-It has been found that provided the rate of press.
rise does not exceed 3 bar per ºCA combustion is
30. I C ENGINES - II
Air Motion & Combustion
• Knock in CI Engines :
-smooth. Between 3 to 4 bar there is tendency to
knock, above this rate of pressure rise the diesel
knock will be prominent.
-Normally audible knock is always present in CI
engines, when it becomes sever and cause heavy
vibrations in the engine , it is said to be knocking. It
is, therefore, a matter of judgment.
-Low ignition temp., ignition delay & speed reduce
knock as also higher CR, Inlet Temp. & press.,
comb. wall temp. cylinder size
31. I C ENGINES - II Air Motion & Combustion
Combustion Chambers for C.I. Engines
CI combustion chamber :
- provide proper mixing of fuel and air in short time
- An organized air movement ;
swirl, turbulence,squish
- produce high relative velocity between fuel
droplets and air
- Shape of combustion chamber control air motion
- CI engines classified as ;
Direct- Injection (DI) & Indirect- Injection (IDI)
32. I C ENGINES - II Air Motion & Combustion
Combustion Chambers for C.I. Engines
CI combustion chamber :
Direct- Injection (DI)
- entire volume of combustion chamber located
in main cylinder where fuel is injected. Also
called open combustion chamber.
Indirect- Injection (IDI)
- Combustion space divided into two parts ;
one part main cyl. & other part in cylinder head
33. I C ENGINES - II Air Motion & Combustion
Combustion Chambers for C.I. Engines
Indirect- Injection (IDI)
- Classified as :
1. Swirl chamber ;
compression swirl generated
2. Precombustion chamber ;
combustion swirl induced
3. Air cell chamber ;
compression & combustion swirl induced