Bütanol / dizel yakıt karışımı ile çalışan bir motorda püskürtme zamanının performans ve emisyonlara etkisi

Abstract

Nüfusun giderek artması, petrol kaynaklarının azalması, çevreye verdikleri zararlar, mevcut enerji kaynaklarının maliyetinin yükselmesi ve çeşitli siyasi nedenlerden dolayı bilim adamları alternatif ve yenilenebilir enerji kaynaklarına yönelmişlerdir. Bu yönelişin ulaşım sektöründe de payı büyüktür. Benzinli ve dizel motorlarda yenilenebilir enerjilerin kullanılması, hibrit, tam elektrikli, su, hidrojen ve çeşitli alkollerle çalışan motorlar alternatif enerji kaynaklarından birkaçıdır. Bu yüksek lisans tez çalışmasında ise, çevreyi kirleten egzoz emisyon değerlerini azaltma ve motor performansını artırma amaçlanmıştır. İs, NOx ve partikül madde değerleri benzinli motora göre daha çok olması sebebiyle dizel motor tercih edilmiştir. Normal bütanol, dizel yakıtına %15 oranında karıştırılmış ve püskürtme zamanının egzoz emisyonlarına ve motor performansına etkileri incelenmiştir.Bu deneysel çalışmada kullanılan motorun standart püskürtme başlangıç değeri, krank mili açısı cinsinden 18o'dir. Deney çalışmaları, motor 2200 1/min hızda sabit tutularak, %100, %75, %50 ve %25 olmak üzere 4 değişik yükte, yakıt pompasının motor ile olan bağlantı yerindeki avans şimlerinin azaltılıp artırılmasıyla 16o, 18o, 20o'de gerçekleştirilmiştir. Elde edilen sonuçlar saf dizel yakıtıyla karşılaştırılmıştır. Standart püskürtme avansında ölçülen karışımın özgül yakıt tüketiminin dizel yakıtına göre yüksek olduğu gözlenmiştir. Karışımın püskürtme avansının arttırılmasıyla (20o KMA) ÖYT'nin azaldığı gözlenmiştir. En düşük egzoz sıcaklığı püskürtme avansının erkene alınmasıyla (20o KMA) ölçülürken, termik verim yine dizelde en yüksek değerdedir. Karışımın standart avanstaki termik verimi, avansın arttırılmasıyla (20o KMA) yükselmiş ve azaltılmasıyla (16o KMA) da düşmüştür. 16o KMA'da en düşük NOx emisyon değerleri elde edilirken, CO emisyonlarında düşüşler görülmüştür. HC emisyonlarında 20o KMA'da az miktarda azalma görülürken, karışımın standart avansında en yüksek değerler ölçülmüştür. İs emisyonlarında ise dizel yakıtına göre önemli düşüşler görülürken, en düşük ölçümler 20o KMA'da alınmıştır. Karışımın avansının geciktirilmesiyle (16o KMA) is emisyonlarında, standart avanstaki is miktarına göre artma gözlenmiştir.

Scientists have changed their research fields towards the alternative and renewable energy resources because of some reasons such as increasing population, decreasing oil reserves, the harmful effects of the oil on the nature, the increase in the cost of the existing energy resources, and various political reasons. This change has important affect also in transportation sector. The usage of the renewable energy in petrol-driven and diesel engines, and the engines that run on hybrid, fully electrical, water, hydrogen, and various alcohols are some examples of the alternative energy resources. In this graduate thesis, it is aimed to study on how to decrease exhaust emission values and how to increase the performance of the engine. The diesel engine was preferred because of having more values in fume, NOx and particulate matter than the petrol-driven engine. Normal butanol is blended to diesel fuel in the proportion of 15%, and the effects of the injection time on the exhaust emission and the performance of the engine are examined.The standard injection initial value of the engine which was used in this study is 18 degree in the value of crank axle angle. The experiments were done with keeping the engine stable on 2200 1/min, in 4 different loads as 100%, 75%, 50%, and 25%, and with increasing and decreasing advance shims which are on the connection of the fuel pump and the engine in the degrees of 16o, 18o, 20o. The results were compared with the results of pure diesel fuel. It was observed that the bsfc of the blend which was measured in standard injection advance was higher than the diesel fuel. It was also observed that the bsfc decreased when increasing the the injection advance of the blend (20o CAA). While the minimum exhaust heat was measured when the injection advance was taken an early time (20o CAA), the thermic efficiency was in the maximum level in the diesel fuel. The thermic efficiency of the blend in the standard advance was increased with increasing the advance (20o CAA) and was decreased with decreasing the advance (20o CAA). While it was obtained the minimum NOx emission values in 16o CAA, decreases were observed in the CO emissions. While it was seen that little decrease in the HC emission in 20o CAA, the maximum levels were measured in the standard advance of the blend. It was also seen that there is important decrease in the fume emissions when it was compared with the diesel fuel. The lowest measurements were observed in 20o CAA. It was also observed some increase in the fume emissions with postponing the advance of the blend (20o CAA) when it was compared with the fume amount in the standard advance.The standard injection initial value of the engine which is used in this study is 18 degree in the value of crank axle angle. The experiments are done with keeping the engine stable on 2200 1/min, in 4 different loads as 100%, 75%, 50%, and 25%, and with increasing and decreasing advance shims which is on the connection of the fuel pump and the engine in the degrees of 16o, 18o, 20o. The results are compared with the results of pure diesel fuel. It is observed that there is some increase in bsfc of the standard injection advance of the blend while it is compared with diesel fuel. While decreasing or increasing the standard injection advance of the blend is resulted as the increase in bsfc, the minimum bsfc is observed in full-load situation in the diesel fuel. While the minimum exhaust heat is measured when the injection advance is taken an early time, the thermic efficiency is in the maximum level in the diesel fuel. The thermic efficiency of the blend in the standard advance is decreased with increasing the advance or vice versa. While it is obtained the minimum NOx emission values in 16o, it is observed that remarkable decrease in the CO emissions. While it is seen that little decrease in the HC emission in 20o, the maximum levels are measured in the standard advance of the blend. It is also seen that there is important decrease in the fume emissions when it is compared with the diesel fuel. The lowest measurements are observed in 16o.