2 ABSTRAK
Pengujian secara langsung adalah cara paling efektif untuk mengetahui performa sebuah mesin, dalam hal ini mesin otto empat langkah berkapasitas 125 cc diuji dengan menggunakan variasi campuran bahan bakar pertamax murni dengan campuran pertamax-kapur barus, dengan jumlah K 1 gr, K 1,5 gr dan campuran K 2 gr , serta dengan manambahkan alat katalitik converter pada knalpot. Pengujian ini dilakukan untuk memperoleh perbandingan nilai kalor bahan bakar, performansi mesin, AFR serta emisi gas buang. Dari hasil pengujian dapat diperoleh nilai kalor bahan bakar atas (HHV) meningkat hingga mencapai nilai 11,87 %, untuk nilai kalor bahan bakar bawah (LHV) meningkat hingga 17,18 %, performansi mesin dengan bahan bakar pertamax dan campuran pertamax-kapur barus dengan menambahkan alat katalitik konverter pada knalpot dapat diperoleh torsi meningkat mencapai 7,82 %, daya meningkat hingga 6,93 %, konsumsi bahan bakar spesifik menurun sebesar 16,76 %, rasio udara bahan bakar meningkat hingga 2,64 %, efisiensi termal menurun hingga 4,82 %, kadar karbon menurun 23, 95%, kadar karbon dioksida menurun 25,18 %,kadar sisa hidro carbon meningkat 82,91 %, kadar sisa oksigen meningkat 6,68 % untuk campuran K 1 gr. Untuk campuran K 1,5 gr dapat diperoleh, HHV meningkat 14, 79 %, LHV meningkat 21,40 %, torsi meningkat hingga 12,17 %, daya meningkat 10,54 % , SFC menurun hingga 28,06 %, rasio udara bahan bakar meningkat 1,69 %, efisiensi termal meningkat 5,51 %, kadar karbon menurun hingga 11,97 %, kadar karbon dioksida menurun hingga 7,03 %, kadar sisa hidro karbon meningkat 50,42 %, kadar sisa oksigen menurun 0,81 %. Untuk campuran K 2 gr dapat diperoleh HHV meningkat 19,70 %, LHV meningkat hingga 28,30 %, torsi meningkat hingga 9,56 %, daya meningkat 5,50 %, SFC menurun hingga 17,16%, rasio udara bahan bakar menurun 4,14 %, efisiensi termal menurun hingga 4,36 %, kadar karbon menurun hingga 9,19 %, kadar karbon dioksida menurun 11,00 %, kadar sisa hidro karbon meningkat 88,22 %, dan kadar sisa oksigen menurun hingga 0,50%.
Kata kunci: Mesin Otto 4 langkah, pertamax, katalitik konverter , kapur barus
3 ABSTRACT
Testing directly is the best effective way to determine the performance of a machine, in this case the machine otto four-stroke 125 cc capacity was tested by using a variation of the fuel mixture pertamax pure with a mixture pertamax-camphor, with the number of K 1 g, K 1, 5 g and 2 g of a mixture of K, as well as by adding catalytic converters in the exhaust apparatus. This testing is done to obtain a comparison of calorific value of fuel, engine performance, AFR and exhaust gas emissions. From the test results can be obtained calorific value of fuel on (HHV) increased to reach a value of 11.87%, for the lower calorific value of fuel (LHV) increased to 17.18%, the performance of the engine with the fuel mixture pertamax, pertamax and- mothballs by adding a catalytic converter in the exhaust may be obtained torque increased to 7.82%, power increased to 6.93%, specific fuel consumption decreased by 16.76%, fuel air ratio increased to 2.64%, efficiency thermal decreased to 4.82%, the carbon content decreased 23, 95%, carbon dioxide levels decreased 25.18%, the rest of the hydro carbon levels increased 82.91%, increased levels of residual oxygen to a mixture of 6.68% K 1 gr. To a mixture of 1.5 g K can be obtained, HHV increased 14, 79%, LHV increased 21.40%, torque increased to 12.17%, power increased 10.54%, SFC decreased to 28.06%, the ratio of air material fuel increased 1.69%, thermal efficiency increased by 5.51%, the carbon content decreased to 11.97%, carbon dioxide levels decreased to 7.03%, residual hydrocarbon content increased 50.42%, residual oxygen levels decreased 0, 81%. To a mixture of K 2 g can be obtained HHV increased by 19.70%, LHV increased to 28.30%, torque increased to 9.56%, power increased 5.50%, SFC decreased to 17.16%, the ratio of air to fuel decreases 4.14%, thermal efficiency decreases to 4.36%, the carbon content decreased to 9.19%, carbon dioxide levels decreased 11.00%, residual hydrocarbon content increased 88.22%, and the residual oxygen content decreases to 0, 50%.
Keywords: Otto 4 stroke engine, pertamax , catalytic converters, camphor
