Mustafa Ilbas

Utilization of LPG and gasoline engine exhaust emissions by microalgae.

The effect of engine exhaust emissions on air pollution is one of the greatest problems that the world is facing today. The study focused on the effects of realistic levels of engine exhaust emissions of liquid petroleum gas (LPG) and gasoline (GSN) on Phormidium sp. and Chlorella sp. Multi parameters including pH, different medial compositions, fuel types, flow rates and biomass concentrations were described in detail. Effects of some growth factors such as triacontanol (TRIA) and salicylic acid (SA) have also been tested. The maximum biomass concentration of Phormidium sp. reached after 15 days at 0.36 and 0.15 g/L initial biomass concentrations were found as 1.160 g/L for LPG emission treated cultures and 1.331 g/L for GSN emission treated cultures, respectively. The corresponding figures were 1.478 g/L for LPG emission treated cultures and 1.636 g/L for GSN emission treated cultures at 0.65 and 0.36 g/L initial Chlorella sp. biomass concentrations. This study highlights the significance of using Phormidium sp. and Chlorella sp. for utilization of LPG and GSN engine exhaust emissions by the help of growth factors.

CFD MODELLING OF A LOW NOx COMBUSTOR FIRED BY NATURAL GAS AND GAS-OIL

This paper describes work directed at modelling a two-inlet cyclone combustor which had been previously designed at UWCC, fired using either natural gas or gas-oil. Model predictions are appraised against results from previous experimental studies on this and similar geometries.

Numerical modelling of effects of hydrogen supply on combustion behaviours of low calorific value coal gases

In this study, the effect of the hydrogen supply on combustion performances and emission levels of low calorific value coal gases has been numerically investigated in a model combustor. The numerical modelling of turbulent diffusion flames has been performed by using a CFD code. k-e model of turbulent flow, the PDF/mixture fraction model of diffusion flame and P-1 radiation model were used in the present study. The flames of coal gases for pure and hydrogen supply cases were modelled to predict its combustion behaviours. There are five cases of testing, i.e., pure generator gas or pure blast-furnace gas and fuels supplied 4%, 5%, 10% and 15% hydrogen by mass. According to the predictions, the combustion performances of generator and blast furnace gases were improved by supplying hydrogen progressively. Similarly, NOx formations of generator and blast furnace gases were increased due to increment of its flame temperatures depending on hydrogen amounts.

Türbülanslı Metan Alevinde Mikrojet Destekli Seyreltici Kullaniminin NOX Emisyonlarına Olan Etkisinin Sayısal Olarak İncelenmesi

Bu calisma kapsaminda, mikrojet destekli metan alevinin yanma ve emisyon karakteristikleri sayisal olarak arastirilmistir. Yapilan modellemelerde, metan alevinin merkezinden mikrojet olarak seyreltici beslenmis ve boylece metan alevinde NO X emisyonlarina olan etkileri arastirilmistir. Seyreltici olarak, CO 2 , N 2 ve H 2 O (su buhari), farkli Reynolds (Re) sayilarinda mikrojet olarak alev bolgesine beslenmistir. Calismada, bir hesaplamali akiskanlar dinamigi (HAD) programi (Ansys Fluent) kullanilmis ve modellemeler bu program ile gerceklestirilmistir. The PDF/Mixture Fraction yanma modeli, P-1 radyasyon modeli ile birlikte, farkli turbulans modelleri de yanma modellemesinde kullanilarak en uygun turbulans modeli belirlenmistir. Yanma modellemesi neticesinde, bu HAD programina ait yanma-sonrasi NO X islemcisi ile metan alevinin isil ve ani NO X olusum mekanizmalarina gore tahminler yapilmis ve seyrelticilerin etkileri sayisal olarak arastirilmistir. Gerceklestirilen yanma modellemeleri neticesinde elde edilen sonuclara gore, yanma odasi merkezinden beslenen seyrelticilerin metan alevinde olusan NO X emisyonlarinin bastirilmasina bir miktar katki sagladigi gorulmustur. Seyrelticiler kendi icerisinde degerlendirilecek olursa, mikrojet seklinde seyreltici olarak su buhari kullaniminin CO 2 ve N 2 ’ye gore metan alevindeki NO X seviyelerini daha fazla dusurdugu tespit edilmistir. Bu deger 45 ppm’den 30 ppm dolaylarina kadar azaltilabilmistir. Yapilan bu sayisal calisma ile birlikte, metan alevinin merkezinden mikrojet seklinde seyreltici beslenmesinin alev stabilizasyonuna etkisi oldugu gibi NO X emisyonlarinin azaltilmasina da katki sagladigi sonucuna varilmistir.

Three-Dimensional Numerical Modelling of Hydrogen, Methane, Propane and Butane Combustions in a Spherical Model Combustor

In this study, combustion and emission characteristics of hydrogen, methane, propane and butane have been numerically investigated in a spherical model combustor. Predictions have been performed by using Ansys Fluent CFD code. The numerical modelling of turbulent non-premixed diffusion flames have been implemented in this combustor. Mathematical models studied in this study included the k–e model of turbulent flow, the PDF/mixture fraction model of non-premixed combustion and P-1 radiation model. Three-dimensional modellings of the model combustor were conducted for same combustion conditions (40 kW thermal power and λ = 1.0 stoichiometric mixture ratio). According to modelling results, the maximum temperature was predicted during the hydrogen combustion as the high diffusivity, reactivity and heating value of hydrogen highly affected the flame temperature. Similarly, the minimum temperature in this model combustor was also predicted during the butane combustion. Moreover, high NOX emissions were formed in high temperature zones because of thermal NOX mechanism. Hence, the maximum NOX formation was predicted for hydrogen combustion among these fuels.