3 research outputs found
Ramalan Dan Ka Walan Keluaran Nox Dari Enjin Diesel Satu Selinder Menggunakan Rangkaian Neural Buatan
Kerja tesis ini berkenaan dengan kajian ujikaji dan simulasi komputer yang digunakan
untuk membina model-model yang sesuai untuk ramalan dan kawalan keluaran nitrogen
oksida (NOx) daripada enjin Diesel Yanmar L60AE-D satu selinder suntikan terus. Hari
ini, enjin Diesel merupakan antara loji kuasa yang terbaik di kalangan semua jenis enjin
pembakaran dalam. Walau bagaimanapun, NOx yang terkandung di dalam gas ekzos
enjin Diesel telah dikenal pasti sebagai elemen yang bertanggungjawab mencemarkan
atmosfera kita dan menyebabkan masalah-masalah kesihatan. Untuk mengurangkan
keluaran pencemaran enjin Diesel, dua aplikasi berdasarkan kepada model-model
rangkaian neural buatan telah dibangunkan. Aplikasi pertama adalah untuk
mendapatkan model ramalan kepekatan keluaran NOx di bawah keadaan kendalian
pelbagai.
This thesis work concerns with an experimental and computer simulation studies used
to develop suitable models to predict and control the oxides of nitrogen (NOx) emitted
from the Yanmar L60AE-D single cylinder direct injection diesel engine, fitted in a
Cusson's Engine Test Bed Model P8160. Today, diesel engine is the most efficient
power plant among all known types of internal combustion engines. However, the NOx
contained in the exhaust gases of diesel engines have been identified as elements
responsible for polluting our atmosphere and causing health problems. In order to
reduce diesel engine polluting emissions, two applications based on artificial neural
network models have been developed. The first application is to obtain the prediction
model of NOx emission concentration under various operating condition
Enhancement Of Producer Gas Quality Through Co2 Absorption Using Cao-Sand Mixture In A Fluidized Bed Reactor
This thesis concerns an experimental study and numerical simulation used to enhance the producer gas quality through carbon dioxide (CO2) absorption using calcium oxide (CaO) - sand mixture in a CO2 bubbling fluidized bed absorption reactor (CO2 BFBAR). Biomass gasification is a thermo-chemical conversion process of solid biomass into gaseous fuel called producer gas that can be used to generate power and electricity. However, carbon dioxide (CO2) content in the producer gas reduces its heating values as CO2 acts as a diluent. The use of limestone consisting mainly of the mineral calcite (calcium oxide, CaO) as calcium based sorbent to absorb CO2 in the producer gas will increase the heating value of the producer gas. 3-D Computational Fluid Dynamics (CFD) software was used to determine hydrodynamic characteristic of CaO-sand bed material in a CO2 BFBAR. The simulation results show that with 100, 500 and 1000 micron particle size of CaO, good fluidization at 15 – 55 L/min volume flow rate of air was achieved. The CO2 BFBAR was developed and the behavior of CaO-sand mixtures in a cold model experiment was studied. The effect of the CaO-sand mixtures, the CaO particle sizes, the volume flow rate and the pressure of air intake were investigated experimentally. The absorption-desorption process of CaO was studied with the thermogravimetric analyzer (TGA) over 1, 4 and a muticycle. Three differents temperature (500, 600 and 700oC) were set a variables. The reaction rate of CaO was obtained. Results show that for number 1 cycle the CO2 absorption
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reaction rate was fast at first stage and then followed with slower reaction rate. About 0.337 and 0.065 mg/min CO2 reaction rate were obtained in rapid and slow absorption regime respectively. It is also observed that the CO2 absorption reaction rates decreases when number of cycle’s desorption-absorption process was increased. After TGA experiment, the hot model experiment was conducted to investigate CO2 absorption at the optimum condition obtained from the cold model experiment. The simulated gas consisting of 20% CO2 and 80% N2 was introduced in the CO2 BFBAR at temperatures of 650-750oC. The CaO percentages of 50 and 40 in sand were found to have a good fluidization at all air pressures (2 - 6 bar). In addition to that, the 1000 micron particle size of the CaO–sand mixture and the volume flow rate of air between 15 – 55 L/min were also found to generate good fluidization. In the hot model experiment, the best CO2 absorption occurs in 50% CaO mixture with simulated gas, at pressure of 3 bar and the volume flow rate of 45 L/min at 650-750oC in the CO2 BFBAR. The CO2 concentration in the simulated producer gas when applied decreases approximately 57.5%, where this resulted in increases of H2 and CO to approximately 12% and 6%, respectively within 10 minutes of operation. For the compressed producer gas, the CO2 concentration decreases approximately 77.4%, where H2 and CO increase approximately 23.3% and 21.7%, respectively. Therefore the heating value of the compressed producer gas increases from 4.51 to maximum of 6.04 MJ/Nm3 an increase of 38%
Design and fabrication of a cleaning cum cooling system for downdraft gasifier / Mohd Mahadzir Mohammud... [et al.]
Biomass is the most abundant resources and available in all parts of Malaysia. It has the potential to be one of the best options for providing theon demand renewable fuel that can be utilized in various energy conversion technologies. The producer gas produced from biomass can be used to power electricity, thermal energy, or transportation fuels. However, the producer gas needs to be cleaned before being used. In the present paper the design and fabrication of cleaning cum cooling system is shown. The cleaning cum cooling system is used to filter the unwanted particle such as dust (particulate matter), tar and to absorb moisture produced by biomass gasification. The objectives are to design the cleaning cum cooling system by using SolidWorks 2016 software, to fabricate the mechanism by lab-scaled dimensions and to cool and clean the producer gas. The cleaning cum cooling system consists of three stages of filter (water scrubber, tar absorber and silica gel). Each filter has the same dimension size that is 110mm diameter and 400 mm height. The material used is Polyvinyl chloride (PVC) pipe. The results showed that temperature output of 30.9o C is obtained at point after the cleaning cum cooling system. Other than that, 8.5 grams of particulate matter and 32 grams of concentrated tar were trapped in the water scrubber and tar absorber filters. For the moisture test, 40 grams of water was found in the silica gels. These show that the producer gas has been cleaned where a blue flame was lastly obtained. It showed the producer gas is in a good condition