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“PERFORMANCE AND EMISSION ANALYSIS OF

DIESEL ENGINE BY INJECTING DIETHYL ETHER

WITH AND WITHOUT EGR USING DPF”

PROJECT REFERENCE NO. : 37S1036

COLLEGE : KS INSTITUTE OF TECHNOLOGY, BANGALORE

BRANCH : MECHANICAL ENGINEERING

GUIDES : NAGAPRASAD K S

STUDENTS : HARISH N

DEVAPPA H S

MALLESHAPPA BADIGER

MANJESH A

Introduction:

The intention of Rudolf Diesel to provide a new type of internal combustion engine

operating with higher efficiency than conventional steam and Otto cycle engines, and that

could be operated on many types of fuels. The engine cycle developed by diesel involves

injection of fuel into a volume of air heated by compression. Over the course of history, the

durable and efficient diesel engine has replaced other less efficient modes of power

production, including steam engines in the railroad industry. A diesel engine or compression-

ignition (C.I.) engine is an internal combustion engine that uses the heat of compression to

initiate ignition to burn the fuel, which is injected into the combustion chamber.

Energy consumption is increasing globally in various forms for different purposes. To

determine the potential of di-ethyl ether (DEE) for use as a transportation fuel, it is necessary

to understand its engine and emissions performance characteristics, as well as what it might

cost. Although DEE has long been known as cold-start aid for engines, knowledge about

using DEE for other applications, such as a significant component of a blend, or as a

complete replacement for diesel fuel is limited[9].

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Exhaust Gas Recirculation (EGR) is a pre-treatment technique, which is being used

widely to reduce and control the oxides of nitrogen (NOx) emission from diesel engines. EGR

controls the NOx because it lowers oxygen concentration and flame temperature of the

working fluid in the combustion chamber. However, the use of EGR leads to a trade-off in

terms of soot emissions. Higher soot generated by EGR leads to long-term usage problems

inside the engines such as higher carbon deposits, lubricating oil degradation and enhanced

engine wear[6].

For many years, diesel engine manufacturers have been working extensively to

develop after treatment technologies that are capable of significantly reducing the emission

levels of each of the primary pollutants which are considered to be a risk to the environment

and public wellbeing. The majority of these after treatment technologies have been designed

with the most consideration being given to compounds such as particulate matter (PM),

oxides of nitrogen (NOx), carbon monoxide (CO), and hydrocarbons (HC). One primary after

treatment technology commonly used to reduce the PM emission levels of diesel exhaust is

the diesel particulate filter (DPF). There are a variety of DPFs available. For example, the

DPF could be made of composite fibrous materials which utilize fine fibers as a means of

particle filtration.

The importance of CI engines is due to

Its higher thermal efficiency than SI engines, and

CI engine fuels being less expensive than SI engine fuels (petrol or gasoline).

These factors make the running cost of CI engines much less than SI engines and hence make

them attractive for all industrial, transport and other applications.

Objectives of the project:

To conduct the experiments on diesel engine using neat diesel with & without EGR at

various loads.

To conduct the experiments by injecting Di-ethyl ether at different proportions with

diesel into the engine running with & without EGR at different loads.

To measure the emission parameters with and without after treatment devicesDiesel

particulate filter (DPF) based on the highest efficiency of the engine.

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To compare the Performance and Emission of diesel engine by injecting neat diesel &

Di-ethyl ether blends having EGR, DPF set up.

Finally, to suggest the optimum operating condition for this existing diesel engine by

considering all the parameters.

Methodology:

Exhaust Gas Recirculation

Exhaust Gas Recirculation is an efficient method to reduce NOx emissions from the

engine. It works by recirculating a quantity of exhaust gas back to the engine cylinders. Inter-

mixing the recirculated gas with incoming air reduces the amount of available O2 to the

combustion and lowers the peak temperature of combustion. Recirculation is usually

achieved by piping a route from the exhaust manifold to the intake manifold. A control valve

within the circuit regulates and times the gas flow.

Uses of Exhaust Gas Recirculation

First, exhaust gas recirculation reduces the concentration of oxygen in the fuel-air

mixture. By replacing some of the oxygen-rich inlet air with relatively oxygen-poor exhaust

gas, there is less oxygen available for the combustion reaction to proceed. Since the rate of a

reaction is always dependent to some degree on the concentration of its reactants in the pre-

reaction mix, the NOx-producing reactions proceed more slowly, which means that less NOx

is formed.

In addition, since there is less oxygen available, the engine must be adjusted to inject

less fuel before each power stroke. Since we are now burning less fuel, there is less heat

available to heat the fluids taking place in the reaction.The combustion reaction therefore

occurs at lower temperature. Since the temperature is lower, and since the rate of the NOx-

forming reaction is lower at lower temperatures, less NOx is formed.

Basic Parts of EGR

There are 3 basic parts of EGR

• EGR Control Valve

• EGR Cooler

• EGR Transfer Pipe

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Fig: 4.1 Relation between EGR ratio and load

Fig: 4.2 Diesel Engine test rig and Exhaust gas recirculation system

Diesel Particulate Filters (DPF)

Diesel particulate traps are devices that physically capture diesel particulates to prevent their

release to the atmosphere. Some of diesel filter materials which have been developed show

quite impressive filtration efficiencies, frequently in excess of 90%, as well as acceptable

mechanical and thermal durability. In fact, diesel traps are the most effective control

technology for the reduction of particulate emissions with high efficiencies. More precisely,

due to the particle deposition mechanisms utilized in these devices, traps are effective in

controlling the solid fraction of diesel particulates, including elemental carbon (soot) and the

related black smoke emission. It must be remembered that traps may have limited

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effectiveness, or be totally ineffective, in controlling the non-solid fractions of PM, such as

the SOF or sulfate particulates. For this reason, trap systems designed to control the total PM

emission are likely to incorporate additional functional components targeting the SOF

emission (e.g., oxidation catalysts) and sulfate particulates.

Due to the low bulk density of diesel particulates, which is typically below 0.1 g/cm3 diesel

particulate filters can quickly accumulate considerable volumes of soot. The collected

particulates would eventually cause excessively high exhaust gas pressure drop in the filter,

which would negatively affect the engine operation. Therefore, diesel filter systems have to

provide a way of removing particulates from the filter to restore its soot collection capacity.

This removal of particulates, known as the filter regeneration, can be performed either

continuously, during regular operation of the filter, or periodically, after a pre-determined

quantity of soot has been accumulated. In either case, the regeneration of filter systems

should be “invisible” to the vehicle driver/operator and should be performed without his

intervention. In most cases, thermal regeneration of diesel filters is employed, where the

collected particulates are removed from the trap by oxidation to gaseous products, primarily

to carbon dioxide (CO2). The thermal regeneration, schematically represented in Fig5.1, is

undoubtedly the cleanest and most attractive method of operating diesel filters.

Fig 5.1 Schematic of Particulate Filter with Thermal Regeneration .

FILTERATION

CO2 PM

HEAT O2

NO

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Experimental Setup

Compression ignition engine

Experiments are conducted on a four stroke multi-cylinder, water cooled compression

ignition engine. The specifications of the engine are shown in the specification table.

Fig 6.1 Compression ignition engine

Hydraulic Dynamometer

Fig 6.2 Hydraulic dynamometer

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The engine is loaded through a water dynamometer setup. The load is applied using

this hydraulic dynamometer.

EGR Connection

Fig 6.3.5 EGR circuit connection

Full experimental Set up

Fig 6.4 Photograph of Diesel Engine test rig

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Diesel Particulate Filter (DPF)

Fig 6.5.1 Wall-Flow substrate Diesel Particulate Filter (DPF)

DPF Arrangement

Fig 6.5.2 DPF arrangement

The Diesel Particulate Filter (DPF) is placed in the exhaust line of the CI engine. The

exhaust gases from the silencer pass through the diesel particulate filter. Thus the exhaust

gases containing the particulate matter gets filtered and clean gases passes to the atmosphere.

DPF is loaded with precious metal and hence enhancing regeneration.

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Results:

The investigation of diesel engine performance is done by blending diesel with diethyl ether

with and without EGR. The analysis is done in the sequence of comparison of performance

obtained at different concentrations of diesel fuel with di-ethyl ether at different ratios of 20%

and 30% for various EGR valve openings.

The variation of brake thermal efficiency and exhaust gas temperature at different load has

been presented and discussed.

The engine speed is kept at a constant speed of 1200rpm with an EGR valve opening of 1/4,

1/2, 3/4, 1.The results were analyzed as follows.

Performance characteristics of Neat Diesel with and without EGR at different loads

running at 1200rpm.

Performance characteristics of Diesel blended with 20% Di-ethyl ether with and

without EGR at different loads running at 1200rpm.

Performance characteristics of Diesel blended with 30% Di-ethyl ether with and

without EGR at different loads running at 1200rpm.

Comparison of Neat Diesel with Di-ethyl ether blends with and without EGR for 16

kg load at 1200rpm.

Emission Measurement for 3/4 EGR valve opening at 16 kg Load.

The comparison and performance of diesel engine at different loads for various valve

openings and at different blending are shown clearly with the graphical representation of

values for different parameters like brake thermal efficiency& exhaust gas temperature.The

emission such as PM, NOx, HC, CO, CO2 is also shown in comparison with neat diesel and

diesel blending with 20% di-ethyl ether and 30% di ethyl ether

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Performance characteristics of Neat Diesel oil with and without EGR at

1200rpm

Comparison of Brake thermal efficiency v/s Load

Fig A.1Brake thermal efficiency v/s Load

The brake thermal efficiency was measured with load for all test turns with and

without EGR at 2, 4, 8 and 12 kg loads. The efficiency has found to decrease gradually by

recirculating the exhaust gas. This happens due to burnt gas occupying the engine cylinder

which thereby reduces the availability of oxygen for combustion. The maximum brake

thermal efficiency has been found to be 6.72% at 12 kgfor without EGR condition as shown

in fig A.1 The minimum brake thermal efficiency for 12kg is with 3/4 EGR valve opening

condition.

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Comparison of Exhaust Gas Temperature v/s load

Fig A.2 Exhaust Gas Temperature v/s Load

The Exhaust Gas Temperature is compared with load for all the test turns with

and without EGR for 0, 2, 4, 8 and 12 kg loads. It is found that Exhaust Gas Temperature

reduces with the application of E.G.R which in turn reduces the NOx pollutant from the

emission.

Conclusions:

After the investigation of diesel engine performance by blending diesel with diethyl

ether (DEE) with and without EGR system, it is shown that no major modifications are

required for EGR installation in the existing engine, except for the fuel. Even though the

brake thermal efficiency of CI engine decreases with EGR system, The injection of DEE has

drastically enhanced the efficiency for more than the normal performance with EGR system.

It is also found that the exhaust gas temperature has decreased with exhaust gas recirculation

for both diesel and DEE blends. Maximum brake thermal efficiency is found to be 4.93% for

30% DEE and ¾ EGR opening at 4KG load. At this optimum condition of engine, DPF will

be attached to the engine exhaust and emission will be measured

At this operating condition the exhaust gas temperature is found to be 114 deg.C which is

lesser than neat diesel operation Particulate matter emission has been decreased at a larger

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rate by the usage of DPF emission has been decreased to a minimum. There has been a

decrease in PM emission of over 95% by the application of DPF Nitrogen oxides (NOx)

emission has considerably reduced with usage of both after treatment devices for with EGR

condition. By all these results we can conclude that the after treatment devices are active in

reducing the engine emissions and are necessary in attaining the emission norms.

Scope for Future Work:

Performance of the diesel engine can be studied for higher injection pressure and by

increasing the injection advance.

Effects of intake air heating and fuel preheating on performance of engine can be

studied.

The controlled quantity of Exhaust gas can be re-circulated to minimize nitrogen

dioxide and nitric oxide emission.

Electronic controlled EGR valve opening can be made, thereby controlling the flow

precisely