Effect of LPG Content on the Performance and Emissions of A Diesel-LPG Dual-Fuel Engine

Abstract

IntroductionThe purpose of internal combustion engines is the production of mechanical power from the chemical energy contained in the fuel. In internal combustion engines, as distinct from external combustion engines, this energy is released by burning the fuel inside the engine cylinder. The fuel-air mixture before combustion and the burned products after combustion are the actual working fluids. The work transfers which provide the desired power output occur directly between these working fluids and the mechanical components of the engine. Because of their simplicity, ruggedness and high power-to-weight ratio, the internal combustion engines have found wide applications in transportation and power generation.In spite of many unconventional sources of energy developed, petroleum based fuels remain the primary source of energy in the field of power and propulsion all over the world. The demand for the petroleum products in India is increasing at an alarming rate. For instance the demand for the petroleum products was about 3.5 Million Metric Tons (MMT) in 1950-51, and in 1997-98 it has risen to about 84.3 MMT, in 2004-05 it has reached an alarming value of 111 MMT. At this rate it is believed that the demand may reach a staggering 234 MMT by 2019-20. The approximate petroleum reservoirs in the world are 700 MMT. The domestic production of crude oil is about 33 MMT and the diesel consumption is 40 MMT, the petroleum oils worth Rs.102500 crores were imported (Hey Wood, 2007).Conventional fuels for internal combustion engines are getting dwindled at an alarming rate, primarily due to exponential rise in the population of automobile users world-wide. These fuels are likely to prevail for another 50-75 years unless newer reservoirs are explored. Further, these fuels, upon their combustion release toxic gases into the atmosphere, causing severe environmental pollution and degradation of the quality of air of the atmosphere. Effect of LPG Content on the Performance and Emissions of AbstractIn the present work, LPG, a by-product of petroleum refining process is used to replace conventional diesel fuel, partially, for improved combustion efficiency and clean burning. A conventional diesel engine was operated on the dual-fuel mode, using LPG as the primary fuel and diesel as the pilot fuel. A four-stroke, single-cylinder diesel engine, most widely used in agricultural sector, has been considered for the purpose of experimentation. The engine was operated at a constant speed of 1500 rpm at a low engine load of 20% and a high engine load of 80%. Under both these operating conditions, combustion, performance and emission characteristics of the engine have been evaluated and compared with that of baseline diesel fuel operation. At 20 % engine load the brake thermal efficiency of the engine has found to decrease with an increase in the LPG content. On the other hand at 80% engine load, it has increased with an increase in the LPG content. Same trend has been observed with regard to the mechanical efficiency. The volumetric ...

The Elbs and Boyland-Sims peroxydisulfate oxidations

“…Rao and Rao have found that increasing the peroxydisulfate-phenol ratio increases the yield for the p -isomers whereas for the o - and m -isomers the opposite is usually found. [15] The set of reactions shown in Scheme 7a is a possible explanation of this situation but fails to account for reality as no detectable oxygen is observed during the reaction between peroxydisulfate and either 2-quinolone or 2-quinolone-4-carboxylic acid. [16]…”

Numerical simulation of the effect of LPG blending on the characteristics of a diesel engine

“…Concerning emissions, the NO x concentration decreases, HC levels slightly increase and CO slightly increases at low engine load but considerably decreases at high engine load with an increase of LPG mass fraction. The performance, combustion characteristics, and emission of a constant speed-single-cylinder, four-stroke diesel engine operated on the (LPG-diesel) dual-fuel have been evaluated and compared with conventional diesel fuel engine at different load conditions by Rao et al 24 At low engine load (20%), the mechanical and brake thermal efficiencies decrease with an increase in the LPG fraction, while at high engine load (80%), they increased with an increase in the LPG fraction. On the other hand, the volumetric efficiency decreased with the LPG fraction at both engine load conditions.…”

The analysis of the possibilities of increasing the share of propane in the fuel mixture supplied to a dual fuel diesel engine

“…This is how gas has become a fuel powering the engines of a transporting vessel. An additional benefit resulting from this type of fueling is the improvement of the environmental performance mainly by a reduction of the emission of particulate matter [5,6,8,10,14]. The economic factor is also important due to the difference in the prices of diesel oil and gaseous fuels.…”