• Applied Chemistry for Engineering
• /
• v.23 no.5
• /
• pp.456-461
• /
• 2012

To verify the utilization of biomass as energy, the combustion characteristic has been studied by an experimental combustion furnace under an isothermal and non-isothermal combustion. The wood pellet, rice straw and rice husk were used as biomass samples in this work. The characteristics of emission gases, dusts and residues from biomass combustion have been analyzed and compared with those of reuse derived fuel (RDF). From isothermal combustion experiments, it was found that the incomplete combustion of rice straw was greater that that of rice husk, wood pellet and RDF. This is due to the fact that the combustion reaction rate of the rice straw was faster than that of other samples, and the oxygen concentration in rice straw combustion was rapidly decreasing. It was also found that $NO_{X}$ concentration of emission gas from wood pellet combustion was the lowest. From non-isothermal combustion experiments, it was found that all samples were burned before $900^{\circ}C$. Also, the temperature range of $NO_{X}$ emission was similar to that of CO emission, on the other hand, $SO_{2}$ was emitted at a higher temperature than that of CO emission.

• 한국연소학회:학술대회논문집
• /
• 2014.11a
• /
• pp.67-70
• /
• 2014

We performed computational simulation for a heat recovery steam generator to predict emissions (especially carbon monoxide) and compare the results with experimental data. We used the steady laminar flamelet model(SLFM) which can consider detailed chemical mechanisms. To reduce the number of grid, we simplified the geometry of the whole heat recovery steam generator. In conclusion, the trend of simulation results is good agreement with experimental data.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2005.11a
• /
• pp.475-478
• /
• 2005

Ducted rocket produces thrust by 2 steps, primary incomplete combustion in the gas generator, and secondary complete combustion reaction in combustion chamber mixed by air taken through duct. the range of a rocket is determined by the weight of propellant, especially the weight of fuel. So ducted rocket has more efficiency and high terminal speed compared to traditional solid rocket motor. This propulsion system expected to be applied to various kinds of missile for anti-aircraft, anti-ship

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 1997.11a
• /
• pp.81-86
• /
• 1997

It is proposed, for fuzzy combustion control system of refuse incinerator to find the relationship between inputs and outputs and to generate rules to control by using rough set theory. It is not easy to find out the corresponding inputs for each output and the control rules with incomplete or imprecise information consisting expert knowledge, process and manipulator values in the field, and operation manual for the given system. Most decision problems can be formulated employing decision table formalism. A decision table on fuzzy combustion control system for refuse incinerator is simplified and produces control(rules). The I/O realtions and the control rules found by rough set theory are compared with the previous result.

• Journal of Climate Change Research
• /
• v.4 no.1
• /
• pp.41-49
• /
• 2013

Recent findings have revealed that black carbon is one of the substantial materials affecting climate change along with greenhouse gases. Usually, black carbon is generated by incomplete combustion of biomass and deposited on snow and ice surface, resulting in increasing adsorption of radiant energy and accelerating ice melting. However, it is still questionable what the emission characteristics of black carbons from biomass combustion is. We investigated the emission characteristics of black carbon generated from a wood stove in this study. We found that the emission of black carbon was highly dependent upon combustion temperature and the amount of combustion air supplied. The emission factors were 1.01 g-BC/kg-Oak for fireplace wood burning under incomplete combustion, 0.37 g-BC/kg-Oak for fireplace wood burning under complete combustion and 0.29 g-BC/kg-Oak for small wood-stove burning.

• Korean Chemical Engineering Research
• /
• v.52 no.2
• /
• pp.256-260
• /
• 2014

Interior of the building is used as a MDF plywood if there is a fire in order to delay the ignition, flame retardant paint, flame retardant solution and flame retardant film are being handled by the flame retardant. Combustion characteristics anf flame retardant performance results can be summarized as follows: General film with a sample showed that short of the criteria in terms of carbonation area, and the results of flame retardant paint, flame retardant solution and flame retardant film products satisfied the criteria. Toxic gases generated in the combustion process results in a film samples using a high incidence of carbon monoxide and the creation of a smoke could be seen. This confirm that is estimated that result from incomplete combustion of PVC film that attach, and displays high toxicity index and hazard class relatively.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.26 no.7
• /
• pp.919-926
• /
• 2002

Down scaled combustor undergoes increased heat loss that results in incomplete combustion or quenching of the flame as a consequence. Therefore, effect of enhanced heat loss should be understood to design a MEMS scale combustion devices. Existing combustion models are inadequate for micro combustors because they were developed for analysis of regular scale combustor where heat loss can be ignored during the flame propagation. In this research a combustion model is proposed in order to estimate the heat loss and predict quenching limit of flame in a down scaled combustor. Heat loss in the burned region is expressed in a convective form as a product of wall surface area, heat transfer coefficient and temperature difference. Comparison to the measurements showed satisfactory agreement of the pressure and temperature drop. Quenching is accounted for by introducing a correlation of quenching parameter and heat loss. The present model predicted burnt fraction of gases with reasonable accuracy and proved to be applicable in thermal design of a micro combustor.

• Journal of Power System Engineering
• /
• v.3 no.3
• /
• pp.44-53
• /
• 1999

This study is concerned with the emission characteristics of kerosene fan heater, which is burned with kerosene and water droplets simultaneously in the burner, in order to prohibit the emissions of harmful exhaust gas and reduce smell caused by incomplete combustion, and the addition of water droplets to the conventional kerosene fan heater was performed by ultrasonic atomizer. For the investigation of this study, the measurement of exhaust gas components and exhaust gas temperature was carried out by using an automatic combustion gas analyser and $NO_x$ analyser, and the measurement of consumption weight of oil and water was obtained by using electric digital balance. Consequently, according as the water percent weight ratio of about $21{\sim}23%$ was supplied for this study, it was found that the combustion-generated $NO_x$ and CO emissions were reduced very largely, but the emissions of $O_2\;and\;CO_2$ and the temperature of exhaust gas were not changed.

• Journal of the Korean Society of Combustion
• /
• v.10 no.2
• /
• pp.1-8
• /
• 2005

Incomplete combustion due to quenching in a narrow confinement has been a major problem for realization of a reliable micro combustion device. In most micro combustors, effects of flows are absent in the quenching because the flow is laminar and no severe stretch is present. In such circumstance, quenching is caused either by heat loss or by removal of active radicals to the wall surface of the confinement. An experimental investigation was carried out to investigate the relative significance of these two causes of quenching of a premixed flame. A premixed jet burner with a rectangular cross section at the exit was built. At the burner exit, the flame stands between two walls with adjustable distance. The gap between the two walls at which quenching occurs was measured at different wall surface conditions. The results were analyzed to estimate the relative significance of heat loss to the wall and the removal of radicals at the surface. The measurements indicated that the quenching distance was independent of the wall surface characteristics such as oxygen vacancy, grain boundary, or impurities at low temperature. At high temperature, however, the surface characteristics strongly affect the quenching distance, implying that radical removal at the wall plays a significant role in the quenching process.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.25 no.3
• /
• pp.336-343
• /
• 2017

Intake air conditions, such as air temperature, pressure, and humidity, are very important parameters that influence engine performance including combustion and emissions characteristics. The purpose of this study is to investigate the effects of intake air temperature on combustion and exhaust emissions characteristics in a single cylinder diesel engine. In this experiment, an air cooler and a heater were installed on the intake air line and a gas flow controller was installed to maintain the flow rate. It was found that intake air temperature induced the evaporation characteristics of the fuel, and it affects the maximum in-cylinder pressure, IMEP(indicated mean effective pressure), and fuel consumption. As the temperature of intake air decreases, the fuel evaporation characteristics deteriorate even as the fuel temperature has reached the auto-ignition temperature, so that ignition delay is prolonged and the maximum pressure of cylinder is also reduced. Based on the increase in intake air temperature, nitrogen oxides(NOx) increased. In addition, the carbon monoxide(CO) and unburned hydrocarbons(UHC) increased due to incomplete fuel combustion at low intake air temperatures.