Engine

The environmental pollution in the metropolitan cities is increasing rapidly mostly because of the increased number of fossil fuel powered vehicles. Many alternative options are now being studied throughout the world. One of the alternative solutions can be a compressed air powered vehicle. The present study focuses on converting an SI engine into a compressed air engine. A two stroke single cylinder SI engine is converted to operate using compressed air because of its design simplicity. The cylinder head of the engine is modified by replacing the existing cam with a set of newly designed flank cam and an inlet-exhaust air passage. As the cylinder head of the engine is modified, the engine is tested for different timing of the valve opening and duration of opening. Three sets of valve timing are used to test the converted compressed air engine. The air pressure used in the present study is 7 bar which is obtained using a compressor. The design and experimental test result presented here can be used for further research and modification of the technique.

Pulse detonation is a propulsion technology that involves detonation of fuel to produce thrust more efficiently than current engine systems. By literature survey and library research it is shown that Pulse Detonation Engine (PDE) technology is more efficient than current engine types by virtue of its mechanical simplicity and thermodynamic efficiency. As the PDE produces a higher specific thrust than comparable ramjet, scramjet engines at speeds of up to approximately Mach 2.3 to Mach 5, it is suitable for use as part of a multi-stage propulsion system. The PDE can provide static thrust for a ramjet or scramjet engine, or operate in combination with turbofan systems. As such, it sees potential applications in many sectors of the aerospace, aeronautic, and military industries. However, there remain engineering challenges that must be overcome before the PDE can see practical use. Current methods for initiating the detonation process need refinement. To this end, many government research bodies and a few private organizations around the world are working on PDS research & further development.

The effect of variable water injection timing on performance and emission characteristics of hydrogen fueled compression ignition (HFCI) engine has been investigated and the results are presented in this paper. In this study, water is injected from 20°BTDC to 20°ATDC with injection duration of 20°CA and 40°CA. Hydrogen is injected at the intake port with fixed injection timing from 0°CA to 40°CA and constant flow rate of 5 LPM. The results indicate that water injection timing of 20°ATDC and duration of 20°CA has shown better engine performance due to increased gross indicated work and indicated thermal efficiency. It has also demonstrated that the lowest NO x concentrations for engine speed greater than 2500 RPM and lower EGT throughout entire speed range. Water injection timing of 20°BTDC and duration of 40°CA has shown the highest heat release rate and the longest ignition delay. Water injection timing of 0°CA and duration of 40°CA indicated that the highest O 2 and SO 2 emissions throughout entire speed range. It is observed that water injection technique appears to be promising method to enhance the performance and emissions quality of HFCI engine effectively. © 2012 Elsevier Ltd.

http://ac.els-cdn.com/S0360544212002769/1-s2.0-S0360544212002769-main.pdf?_tid=5a5e1e0a-a9c7-11e3-a15a-00000aacb362&acdnat=1394616123_08065d37644f93c70a0d3073259afb2c

In the 21st century, automobile industries are increasing at an unimaginable space. A huge problem of internal combustion (IC) engines is that it is a main cause of noise pollution. That is the reason mufflers are used to reduce the noise produced. Though mufflers are not designed to serve any primary exhaust function, they are installed within the exhaust system of most IC engines. It is designed as a soundproofing device that reduces the loudness of the pressure created by the engine. But mufflers need design and geometry considering the physics behind it which is very confounded. Established muffler design has been an iterative process by trial and error method. With recent research in this area has made it possible to do it in an analytical and experimental way.
There are two types of muffler, absorption type muffler and reactive muffler. The project dealt with the complexity behind the different mufflers and finally designed and constructed an absorption type muffler. After constructing the muffler according to our design using mild steel sheet and steel wool, we compared its performance based on three cases, no muffler condition, laboratory muffler condition and our newly designed muffler condition. Each case we calculated the insertion loss, brake specific fuel consumption (BSFC) and specific fuel consumption (SFC). And finally we showed with graphical representation that, our designed muffler performed better than the laboratory muffler condition and no muffler condition.
Of course, we did not achieve our desired result, since mild steel is no longer used as the construction material anymore and the available steel wool was not quality as we expected. However, we hope using better construction material and our design will certainly reduce the sound pressure level a great deal.

Wood charcoal gasification can produce low tar content in its producer gas. The
producer gas is suitable to use in gasoline and diesel engine as fuel. This research
aims to get the stability of producer gas from wood charcoal gasification and the
savings of diesel and gasoline fuel in operating dual fuel engine. Tests were carried
out on each electric load of 0 kW, 0.3 kW, 0.5 kW, 0.7 kW, 1 kW for diesel engines and
0 kW, 0.3 kW, 0.5 kW, 0.7 kW for gasoline engine. The test results showed that the
wood charcoal gasification process took place at a air-fuel ratio were 1.7 – 2. The
range of combustible gas stability was 91 – 105 min. Diesel and gasoline fuel
consumption rate in dual fuel operation were 0.1 l/h to 0.2 l/h and 0.2 l/h to 0.37 l/h
respectively. The average of diesel and gasoline fuel savings were each of 65.8 % and
19.8 % respectively.

This paper studies the effect of the change in air-fuel ratio on the engine and
automobiles vibrations. Principle of vibration analysis is used to determine the system
behavior. Air-fuel ratio is studied, as an input parameter, for stoichiometric, rich and
lean fuels. Such changes in air-fuel ratios makes the engine and so the automobile to
vibrate significantly. A benzene automobile with1800 CC - 4 cylinders engine is tested
and an accurate vibrometer is used to sense such vibrations. It is found that there is
an effect for the air-fuel mixture on the vibration of the engine and on the car as a whole.
Rich mixtures have the highest frequencies at most record time. It is theoretically expected
due to the high energy released by the combustion in which all of the oxygen is consumed

The combustion of fuel inside the internal combustion engine lead to form many by-products like CO2, CO, Exhaust hydrocarbons, various oxides of nitrogen and compound like soot basically known as carboneous deposits. To sustain the engine performance and emission control, this soot must be clean out. This literature contains various mechanical and chemical methods for carbon deposits cleaning, also the formation and adverse effect of soot formation on internal combustion engine. The conventional methods show their performance appreciably on various parameters, but still there is need of a cleaning system that can vanish out all the battle-necks of conventional methods. This literature will also give review about the automated system which will overcome all the drawbacks of conventional methods.

ABSTRACT Alternative fuels have been developed for the commercial diesel products Mk1 and EN590. Appropriate additives were selected from a broad range of oxygenates including alcohols, acetals, ethers, esters, and nitrates by a process of systematic elimination. The resulting fuels called Biodiesel 15 meet all existing standards in force for diesel fuel, are stable, and have similar performance characteristics to standard diesel. Significantly Biodiesel 15 is much cleaner than standard diesel with around 30 per cent or more reductions in particulate matter in the exhaust emissions. Carbon dioxide (CO2) emissions are much lower with Biodiesel 15 than with standard diesel products. Other regulated emissions are on a par with Mk1. The fuel consumption of Biodiesel 15 is 2 per cent lower than that of conventional Mk1.

Wood charcoal gasification can produce low tar content in its producer gas. The producer gas is suitable to use in gasoline and diesel engine as fuel. This research aims to get the stability of producer gas from wood charcoal gasification and the savings of diesel and gasoline fuel in operating dual fuel engine. Tests were carried out on each electric load of 0 kW, 0.3 kW, 0.5 kW, 0.7 kW, 1 kW for diesel engines and 0 kW, 0.3 kW, 0.5 kW, 0.7 kW for gasoline engine. The test results showed that the wood charcoal gasification process took place at a air-fuel ratio were 1.7-2. The range of combustible gas stability was 91-105 min. Diesel and gasoline fuel consumption rate in dual fuel operation were 0.1 l/h to 0.2 l/h and 0.2 l/h to 0.37 l/h respectively. The average of diesel and gasoline fuel savings were each of 65.8 % and 19.8 % respectively.

The sprays from a high-pressure multi-hole nozzle injected into a constant-volume chamber have been visualized and quantified in terms of droplet velocity and diameter with a two-component phase Doppler anemometry (PDA) system at injection pressures up to 200 bar and chamber pressures varying from atmospheric to 12 bar. The flow characteristics within the injection system were quantified by means of a fuel injection equipment (FIE) one-dimensional model, providing the injection rate and the injection velocity in the presence of hole cavitation, by an in-house three-dimensional computational fluid dynamics (CFD) model providing the detailed flow distribution for various combinations of nozzle hole configurations, and by a fuel atomization model giving estimates of the droplet size very near to the nozzle exit. The overall spray angle relative to the axis of the injector was found to be almost independent of injection and chamber pressure, a significant advantage relative to swirl pressure atomizers. Temporal droplet velocities were found to increase sharply at the start of injection and then to remain unchanged during the main part of injection, before decreasing rapidly towards the end of injection. The spatial droplet velocity profiles were jet-like at all axial locations, with the local velocity maximum found at the centre of the jet. Within the measured range, the effect of injection pressure on droplet size was rather small while the increase in chamber pressure from atmospheric to 12 bar resulted in much smaller droplet velocities, by up to four-fold, and larger droplet sizes by up to 40 per cent.