STRATEGI MENGATASI PENYEBAB SURGING MESIN DIESEL PENGGERAK UTAMA DI MT. ONTARI

Turbocharger adalah sebuah komponen untuk menambah jumlah udara yang masuk kedalam silinder dengan memanfaatkan energi gas buang. Kualitas gas buang sangat mempengaruhi putaran turbin turbocharger.. Metode penelitian yang digunakan dalam penelitian ini adalah metode deskriptif kualitatif. Teknik analisa data menggunakan metode SWOT untuk menganalisa faktor-faktor yang menyebabkan surging Mesin Diesel Penggerak Utama dan upaya yang dilakukan untuk mengatasi faktor–faktor tersebut dengan mengidentifikasi kekuatan, kelemahan, peluang, dan ancaman. Berdasarkan hasil penelitian yang telah dilakukan Peneliti, penyebab surging Mesin Diesel Penggerak Utama disebabkan oleh dua faktor, yaitu lolosnya kompresi pada saat pembakaran karena oversize cylinder liner dan suplai suku cadang Mesin Induk di atas kapal terhambat.Untuk mengatasi faktor-faktor tersebut dapat dilakukan dengan mengganti cylinder liner yang sudah oversize, menurunkan putaran Mesin Induk agar gas buang lebih stabil, mengurangi konsumsi minyak lumas silinder untuk mengurangi lumpur pembakaran di ruang udara bilas, mengoperasikan auxiliary blower menjadi manual untuk menjaga tekanan udara bilas dalam tekanan normal selama Mesin Induk beroperasi, rekondisi pada suku cadang Mesin Induk seperti piston crown dan piston ring dengan cara membersihkan sehingga dapat digunakan lagi untuk sementara waktu menunggu suku cadang tiba di atas kapal, dan melakukan pembelian suku cadang dengan uang kapal terhadap suku cadang yang sifatnya ringan dan terjangkau untuk perawatan dan perbaikan suku cadang Mesin Induk.

OBSERVATIONAL ANALYSIS ON RESULT OF YSZ COATED PISTON CROWN ON THE BEHAVIOUR OF A PETROL ENGINE

An observational study of thermal barrier coating (TBC) on the working of 4-stroke single cylinder petrol engine was studied. Yttria Stabilized Zirconia (YSZ) used as coating material. YSZ has less thermal conductivity, sustainability under high temperature and pressure. Main aim of TBC is to decrease heat losses to the cooling jacket of the engine. YSZ is coated on the piston crown by Plasma spray method. YSZ coating improves the performance of petrol engine. Experimental study was carried out on 4-stroke single cylinder OHV petrol engine 25‎°C inclined cylinder horizontal shaft engine on performance of ceramic coated engine and compared with baseline engine under different speed. Results show that ceramic coated engine is more effective than conventional engine as brake specific fuel consumption (BSFC) is reduced 2-4% than normal piston engine, brake thermal efficiency (BTE) of modified engine is expanded 4-8% than unmodified engine. Indicated thermal efficiency (ITE) of modified piston engine is increased 5-10% than normal engine. Mechanical efficiency (ME) of the TBC engine is increased 4-10% than standard engine. Volumetric efficiency (VE) of modified engine is decreased 3-9% when compared with standard engine and exhaust gas temperature (EGT) of ceramic coated engine is increased 1-3% than unmodified engine. KEYWORDS: Petrol Engine, Thermal barrier coating (TBC), Yttria Stabilized Zirconia (YSZ). Mechanical Efficiency

Analysis of Performance characteristics of an Internal Combustion Engine with Thermal barrier coated piston

Investigation of the thermal analysis of a conventional (uncoated) diesel piston made up of Aluminum silicon alloy was carried out in this present study. Secondly, thermal analysis was performed on piston crown, coated with 20% Al2O3 & 80% Yttria Stabilized Zirconia material. TBC comes with two layers; the first layer is a bond coating with NiCoCrAlY compound. The second layer with TBC material (20% Aluminum oxide & 80% Yttria Stabilized Zirconia). The method of multilayer coating was achieved through the Air Plasma spraying technique. Using the coated piston the required temperature in the combustion chamber will be maintained. This will reduce the heat loss to the piston. This reduction in the heat loss will be used to burn the un-burnt gases thereby reducing the polluted exhaust gases. Result will be shown as the thermal efficiency of the coated piston at full load will be increased than uncoated piston and the oxides of nitrogen will be increased.

Control of Exhaust Emissions Using Piston Coating on Two-StrokeSI Engines with Gasoline Blends

An increase in fuel utilization to internal combustion engines, variation in gasoline price, reduction of the fossil fuels and natural resources, needs less carbon content in fuel to find an alternative fuel. This paper presents a comparative study of various gasoline blends in a single-cylinder two-stroke SI engine. The present experimental investigation with gasoline blends of butanol and propanol and magnesium partially stabilized zirconium (Mg-PSZ) as thermal barrier coating on piston crown of 100 µm. The samples of gasoline blends were blended with petrol in 1:4 ratios: 20 % of butanol and 80 % of gasoline; 20 % of propanol and 80 % of gasoline. In this work, the following engine characteristics of brake thermal efficiency (BTH), specific fuel consumption (SFC), HC, and CO emissions were measured for both coated and non-coated pistons. Experiments have shown that the thermal efficiency is increased by 2.2 % at P20. The specific fuel consumption is minimized by 2.2 % at P20. Exhaust emissions are minimized by 2.0 % of HC and 2.4 % of CO at B20. The results strongly indicate that the combination of thermal barrier coatings and gasoline blends can improve engine performance and reduce exhaust emissions.

Performance and Emissions Comparison between Biomethane and Natural Gas Fuel in Passenger Vehicles: results of the second testing campaign

The present paper illustrates the results of the second set of measurements carried out in the BiomethER project (EU-LIFE). BiomethER aimed to design and build two innovative bio-methane production plants, located in the Emilia Romagna region (Italy), so it aims to demonstrate that bio‑methane could replace traditional methane in several applications. One of these applications is road transport where bio-methane can fuel a compressed natural gas (CNG) vehicle. So, three passenger cars have been tested with two gases: conventional natural gas and bio-methane coming from a BiomethER plant. For each vehicle have been measured the emissions and performances on the chassis dynamometer, while an inspection of combustion chambers of the engines was carried out to evaluate their wear condition. This campaign confirms results achieved in the first one, there are no appreciable deviations for fuel consumption and CO2 emissions between the two fuels, acceleration and maximum power were almost the same for the three vehicles tested. Indeed, the vehicle fuelled by methane has significant carbon deposits on the piston crown while the bio-methane fuelled do not have the same.

Selection of optimal technological parameters of thermal protection galvanic plasma coatings for restoration of piston crown made of AK12MMgN alloy

The possibility for creating of high-hard protective wear-resistant and thermal protection coatings by the galvanic plasma method on the AlSi12Cu aluminum alloy in order to improve the operating characteristics of the pistons of internal combustion engine is shown. The effect of technological modes and electrolyte composition on the structure and composition of the resulting coating is established.