Investigation of tail pipe breakdown incident for 110 kV cable termination and proposal of fault prevention

Automotive muffler is a component used to reduce the noise of high pressure exhaust gases that are produced from the internal combustion engine. The main objective of this study is to analyse the effect of the muffler parameter to the sound pressure level (SPL) at the tail pipe noise using GT-Power simulation software. The muffler runs with a Proton Iriz engine model at engine speed from 1000 RPM to 6000 RPM at full load condition. The parameter of each muffler model was compared to determine the most suitable model to reduce the noise at tail pipe with lower backpressure difference. The results obtained was compared with those from previous research as a means of benchmarking. The muffler model should not produce a backpressure difference of more than 5% from the benchmark systems. It is found that the most suitable model in reducing the tail pipe noises is Model B, which manage to reduce the noise by 3.07% (average) of the sound pressure level with backpressure difference of 0.35% only by only reducing the perforates number and shorten the perforates length.

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An Efficient Numerical Model of Pulsating Combustion and Its Experimental Validation

Volume 3: Combustion Science and Engineering ◽

10.1115/imece2009-10439 ◽

2009 ◽

Author(s):

Luca Casarsa ◽

Pietro Giannattasio ◽

Diego Micheli

Keyword(s):

Numerical Model ◽

Combustion Chamber ◽

Second Order ◽

Operating Conditions ◽

Gas Dynamics Equations ◽

Time Step ◽

Flow Equations ◽

Tail Pipe ◽

Flux Difference ◽

Pulse Jet

A simple and efficient numerical model is presented for the simulation of pulse combustors. It is based on the numerical solution of the quasi-1D unsteady flow equations and on phenomenological sub-models of turbulence and combustion. The gas dynamics equations are solved by using the Flux Difference Splitting (FDS) technique, a finite-volume upwind numerical scheme, and ENO reconstructions to obtain second-order accurate non-oscillatory solutions. The numerical fluxes computed at the cell interfaces are used to transport also the reacting species, their formation energy and the turbulent kinetic energy. The combustion progress in each cell is evaluated explicitly at the end of each time step according to a second-order overall reaction kinetics. In this way, the computations of gas dynamic evolution and heat release are decoupled, which makes the model particularly simple and efficient. A comprehensive set of measurements has been performed on a small Helmholtz type pulse-jet in order to validate the model. Air and fuel consumptions, wall temperatures, pressure cycles in both combustion chamber and tail-pipe, and instantaneous thrust have been recorded in different operating conditions of the device. The comparison between numerical and experimental results turns out to be satisfactory in all the working conditions of the pulse-jet. In particular, accurate predictions are obtained of the device operating frequency and of shape, amplitude and phase of the pressure waves in both combustion chamber and tail-pipe.

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Properties and Emissions from Diesel Blended with Spent Groundnut Oil Methyl Ester as Fuel in aCompression Ignition Engine

Applied Engineering in Agriculture ◽

10.13031/aea.13458 ◽

2019 ◽

Vol 35 (6) ◽

pp. 1057-1065

Author(s):

Isaac N Itodo ◽

Rimamnuskep Stephen ◽

Theresa K Kaankuka

Keyword(s):

Methyl Ester ◽

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Flash Point ◽

Carbon Residue ◽

Engine Fuel ◽

Groundnut Oil ◽

Gas Emissions ◽

Tail Pipe ◽

Significant Difference

Abstract. Cheap renewable fuels are needed to replace fossil fuels to reduce greenhouse gas emissions that are causing global warming with the attendant negative consequences. The properties of blends of spent groundnut oil methyl ester (SGOME) and fossil diesel and the emissions from these blends as engine fuel were determined. Spent groundnut oil (SGO) was transesterified into SGOME using methanol and potassium hydroxide as catalyst. The SGOME was blended with fossil diesel and the properties determined and compared to fossil diesel (B0). The pure SGOME (B100) was blended with 90%, 80%, 70%, 60%, and 50% diesel to obtain the B10, B20, B30, B40, and B50 blends of biodiesel, respectively. The properties of the SGOME and the blends were determined according to ASTM and AOCS standards for biodiesel. The properties determined were flash point, carbon residue after combustion, pour and cloud points, kinematic and dynamic viscosities. The blends were used as fuel in a single cylinder 4-stroke water-cooled compression ignition engine that was coupled to a dynamometer from which the tail pipe emissions were measured using gas analyzers. The emissions were measured after the engine had reached a steady state at no load (0 kW) and 1 kW at 3 min interval for 15 min for each blend in 3 replicates. The greenhouse gas emissions measured were nitrogen oxide (NOx),hydrogen sulphide (H2S), particulate matter (PM), sulphur dioxide(SO2),and carbon monoxide (CO). The analysis of variance (ANOVA) at p = 0.05 was used to determine if there was significant difference in the amount of gas emitted from the various blend fuels. The F-LSD was used to separate the means where there was significant difference. The higher blends of the SGOME had better flash point, pour point, and dynamic viscosity than the lower blends. However, the lower blends had better cloud point. The carbon residue after combustion of the SGOME blends was better than that of the fossil diesel. The NOx, PM, SO2, and CO emissions were significantly different from the various blends of the SGOME. However, the H2S emission was not significantly different. Loading the engine did not significantly affect the NOx, H2S, SO2, and CO emissions but significantly affected the PM emission. The PM, CO, and SO2 emissions were highest from the fossil diesel and the lower blends (B10, B20, and B30) and lowest from the higher blends (B40, B50, and B100) at both engine loads. The NOx emission was lowest from the fossil diesel and the lower blends. The use of B20 increased the NOx emission by 10% at both engine loads. The H2S emission was the same for the fossil diesel, pure SGOME (B100), and the blends (B10–B50) at both engine loads. The SGOME fuel reduced tail pipe emission of PM, CO, and SO2 by 26%, 45%, and 78%, respectively. The higher blends had a considerably lower amount of toxic emissions at both engine loads. Keywords: Blends, Diesel, Emissions, Engine, Fuel, Properties, Spent groundnut oil methyl ester.

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