التأثير المشترك لإعادة تدوير غازات العادم والمجال المغناطيسي على أداء وانبعاثات محرك ديزل يعمل بخلطات الوقود الحيوي مع طلاء سيراميكي نانوي

الباحث

قصي عدنان مهدي

المشرف

محمود عبد الحسين مشكور - ابتهال عبد الرزاق محمود

الجامعة

الجامعة التكنولوجية

الكلية / القسم

قسم الهندسة الميكانيكية / الهندسة الميكانيكية

الشهادة

دكتوراه

السنة

2022

لغة الرسالة

انكليزي

الكلمات المفتاحية

EGR;Magnetic field;Biofuel blends;Nano ceramic coating

The impact of a nano ceramic coating and waste cooking oil biodiesel fuel blending on the combustion characteristics and emissions of a compression ignition engine with the combined impact of the cooler exhaust gas recirculation and magnetic field was studied. The rig test was a direct injection model Kirloskar (TV1) 4-stroke single, diesel engine. Using biodiesel blended diesel fuel, this engine was tested at a constant speed (1500 rpm) and under various load conditions. The experiments were conducted using variable engine parameters such as compression ratio (15:1, 16:1, 17:1, 18:1), injection timing (19, 21, 23, 27) bTDC, magnetic fields (4000, 6000, 8000, 12000), injection pressure (175,200, 225, 250) bar, and engine loads (0%, 25%, 50%, 75%, 100%). The Minitab18 software simulation was applied, where the design of the experiments was utilized to identify the optimum system parameters for engine efficiency, and the Taguchi approach (DOE) has been used. The Taguchi technique of the investigation parameters' results were identified, including compression ratio (18:1), injection timing (23 ̊ bTDC), magnetic field (8000 Gauss) and injection pressure (200) bar at full load, biodiesel blend (B10), and EGR (10%). The results showed at a lower value of compression ratio, the combustion becomes nosily (a knocking phenomenon) exactly below CR18:1. The intensity of knocking becomes more abnormal as the compression ratio increases from 15:1 to 16:1, and also appears at 17:1, and totally disappears at 18:1. The advance of combustion by 4° led to a loss in engine power and economy, due to the more frequent fuel injection. Similarly, combustion delayed by 4° led to a loss of engine power due to poor mixture and abnormal combustion (knock combustion) taking place. Increasing injection pressure by 15% led to improved engine performance, but increasing cylinder pressure by 30% led to knocking combustion. Also, increasing the injection pressure by 45% led to increased cylinder pressure and a loss in engine power. By rasing the magentic intensity by 50% (i.e., 6000 Gauss), the engine brake thermal efficiency started increasing, while rasing the magentic field by 100%, the engine reaches optiumn conditions (i.e., 8000 Gauss magentic intensity). The engine emssions decrease, such as CO, UHC, NOx, and smoke opacity. With an acceptable increasing range in CO2. The ignition delay period for B10, B20, DF, B30, B40 percent bTDC was 13.85o, 14.48o, 14.5o, 14.55o, and 14.72o for B10, B20, DF, B30, and B40 percent bTDC when the engine was tested under combined impact. The results manifested that the B10+EGR10+8000 Gauss field and the fuel are under optimum polarized conditions. The maximum value of biodiesel heat release rate is (44.9, 42.9, 42.44, and 39.9 J/oCA). The thermal adiabatic treatment of engine parts such as the head of a cylinder, valves, and the engine piston with a (350 μm bond coat+650μm) results in more than 25% thermal efficiencies that are significantly higher than the baseline. The 0.5 mm adiabatic engine parts improve the efficiency as the load increases, performing up to 20.01% improved more than the uninsulated engine at high engine loads. At low load, BSFC was observed to be reduced by 35.6% for diesel fuel operation compared with the coated engine by 1mm. At high load, the BSFC difference begins to diminish to 24.1%. The un-adiabatic combustion chamber with a biodiesel fuel exhibited a lower BSFC than biodiesel operated under the combined effect due to an enhancement in (CN). At load 100% for bio diesel and maximum CR, 10% for cooler EGR, and 8000 Gauss the decreasing in monoxide values was (30.84%) for 1mm coatings (i.e.,) when the engine is working with a thicker insulation layer. TBC coating produces a rise in CO2 emissions at all loads, with such a significant 19.6% rise at 75 percent of full load and 1500 rpm. For the same engine load of 100 percent, the combined impact and adiabatic operation produced lowed unburned hydrocarbon about of 35 ppm and 28 ppm, respectively. Higher levels of HC emission 54 ppm, are observed at uncoated diesel, and HC decreases to 48 ppm when the engine operation conditions becomes B10+EGR10+8000Gauss corresponding to partially load. . Also, the maximum levels of HC pollutant have been detected at uncoated engine. Due to the dilution effect of cooling EGR system, and the intensity of coated nitrogen absorption, and the presence of magnetic field make the NOx in minimization levels. Smoke opacity recorded a minimum level, especially in 1mm coating, this corresponding to higher temperatures levels of coating surfaces. The top coat nanostructures, which exhibit a tri-modal distribution, characterization of the coatings' surface was done using field emission-scanning electron microscopy (FE-SEM). The nano coating having pinholes and micro-cracks can be seen on the outer surface (nano YSZ surface) of TBCs, which are primarily related to the characteristics of air plasma sprayed coatings. Because of the nanostructure's compactness, the nanostructured YSZ coating surface has fewer pinholes, voids, and microcracks. Tri-modal distributions were semi-molten (nano zones), lamellar layers with columnar grains, and some equiaxed grains. In the polished cross section of coating for both thicknesses the inter face region appears as competence and no voids are splashed. NiCrAlY was a fit choice as bond material. From the XRD pattern of top surface, and for all samples there was no phase transformation of nano ceramic coating. No thermal growth oxidization (TGO) formulation in 500 μm cylinder head, and valves after 225 hrs. testing except piston TGO layer with wavering distributions. And cracking and delamination take place in both intake and exhaust valves in a thicker 1mm engine coating. For thicker coating TGO formation in cylinder head, intake and exhaust valves and disappearing in the engine piston. The vertical cracking and horizontal take place in both cylinder head and valves in thicker coating, while thin layer coating has a horizontal cracking. Hardness of all parts increasing after 225 hrs. testing in engine, except the diesel engine intake and exhaust valve. Porosity for all parts reducing due to densification is generated by the sintering process, except 0.5mm piston and 1mm valves.

طلب نسخة من الملف

الملفات غير منشورة على الموقع. اترك بياناتك وسيتواصل معك موظفو قسم الشؤون الثقافية والفنون لإرسال النسخة مجاناً.

الاسم

رقم الهاتف

البريد الإلكتروني

الغرض من الطلب (اختياري)

إرسال الطلب