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The study aims to investigate the effect of Al2O3 and Al additions to Nickel-base superalloys as a coating layer on oxidation resistance, and structural behavior of nickel superalloys such as IN 738 LC. Nickel-base superalloys are popular as base materials for hot components in industrial gas turbines such as blades due to their superior mechanical performance and high-temperature oxidation resistance, but the combustion gases' existence generates hot oxidation at high temperatures for long durations of time, resulting in corrosion of turbine blades which lead to massive economic losses. Turbine blades used in Iraqi electrical gas power stations require costly maintenance using traditional processes regularly. These blades are made of nickel superalloys such as IN 738 LC(Inconel 738). Few scientists investigated the impact of Al2O3 or Al additions to Nickel-base superalloys as coating layer by using the slurry coating method on oxidation resistance to enhance the Nickel-base superalloy's oxidation resistance. In this study, IN 738 LC is coated with two different coating percentages, the first being (10 Al+90 Al2O3) and the second being (40 Al+60 Al2O3). Scanning Electron Microscope (SEM) and X-Ray Diffraction (XRD) were performed on all samples before and after oxidation. According to the results, SEM images of the surface revealed that the layer of the surface has a relatively moderated porosity value and that some of the coating layers contain micro-cracks. The best surface roughness of specimens coated with 60 % alumina+40 % aluminum was 5.752 nm. Whereas, the surface roughness of specimens coated with 90 % alumina+10 % aluminum was 6.367 nm.Results reveal that alloys with both Al2O3 and Al additions have reported a positive synergistic effect of the Al2O3and Al additions on oxidation resistance. Moreover,the NiCrAl2O3 thermal coating has good oxidation resistance and the effective temperature of anti-oxidation is raised to 1100 °C in turn reducing the maintenanc

The dust accumulation is an undesirable phenomenon in a solar plant environment. The dust removing procedures were using traditional techniques which are led to more loss in power especially in desert areas. Additionally, most of the cleaning techniques are designed according to the concept of vanquishing the adhesive force of dust particles by adding a harmonic excitation force. This force may produce damage to the solar panel. Therefore, the main objective of the current study is to simulate a traditional solar panel model BSP32-10 with ANSYS software throw an additional external force (2, 4, 6, 10, and 15 Newton) throws six mode shapes and verified experimentally. Deformation values of solar panel surface increase with an increase in excitation force, and not exceed the natural frequency deformation, with average values from 0.07 to 1.5 mm, while 94% of these results are close to experimental work during verification action. Middle position of the solar panel for excitation force on the solar panel in the dust removal concept is the best position.

Diesel engines produce high emissions of smoke, particulate matter and nitrogen oxide. The challenge today is to reduce exhaust emissions without making any major modifications on engine. Therefore, adding alternative fuel will be the best practical pick to improve the performance and cut down emissions from diesel engines. The air fuel mixer plays an important role to convert diesel engine to work with dual fuel mode (alternative fuel-diesel) without any change in engine. One problem of gaseous mixers is the disability to prepare a homogeneous air-fuel mixture at a specific air-fuel ratio before entering the engine, thereby leading to high brake specific fuel consumption and exhaust emissions. This study offers an overview of air fuel mixer types. According to, overview in the dual-fuel engines, the combustion efficiency, engine performance and the emission reduction of gases are directly proportional to the degree of homogeneous mixing and air fuel ratio, all that depend on the design of mixer (size, shape, number of holes) and control mechanism that control on the mixer.

Many research works have intended to enhance fuel economy and decrease emissions during conversion from a diesel engine to a dual fuel engine. However, the majority of these works do not take into account enhancement of homogeneity of the mixture inside the engine and precise control of the air fuel ratio. This deficiency can cause higher emissions, greater brake-specific fuel consumption, and likely knocking. Conversely, there is limited research pertaining to empirical equations for projecting the mixture’s homogeneity. In this study, a new air–fuel mixer was devised, produced and tested. For the air-gaseous fuel mixer, the proposed design was meant to be appropriate for mixing air with hydrogen and CNG. It was also designed in such a way that it would result into extremely homogeneous mixing for the gaseous fuel as it mixes with air and exhibits high uniformity index (UI). Lastly, it is also meant to promote easy connection with an electronic control unit so that the air-gaseous fuel ratio could be accurately controlled for varying engine speeds. To optimise the homogeneity within the new mixer, fifteen varying mixer models having 116 cases were made in order to study how the location, diameter, and number of holes within the mixer affect the mixture’s homogeneity and distribution under ACNGR = 34.15 and AHR = 74.76. Afterwards, the distribution, flow behaviour, and homogeneity of the mixture within the new mixer models were checked using computational fluid dynamics analysis software. Based on the simulation results, it was discovered that the best uniformity index (UI) values were achieved for models 7/ case 48. Based on the simulation results, a fairly simple method was then developed to estimate the mixture’s homogeneity (UI) from the new models of the mixer. The basis of the proposal model (empirical equation) is from the best values determined for the unknown constant F so that the equation for UI estimation could be formulated. The particle swarm optimisat

A mixer is a device for mixing the proper amount of fuel with air before admission to the combustion chamber. Although an air–fuel mixer easily converts a diesel engine into a dual-fuel engine, and a petrol engine to a bi engine, the problem with gaseous mixers is the inability to prepare a homogeneous mixture of air and gaseous fuel at various engine speeds, and weak performance in controlling the AFR (air-fuel ratio) at various engine speeds. According to previous studies, no mixer has yet been designed for mixing H-CNG-air for tri-fuel engines (H-CNGDiesel engines). Moreover, the existing available mixers were unable to work under different engine modes (such as dual fuel or bi engine), different capacities of engine, or different mix of gaseous fuels. In this present work, a new air–HCNG mixer was designed and developed to be suitable for mixing air with (Hydrogen), (CNG) and (HCNG) under different modes (bi-engine, dual fuel engine, tri-fuel engine). In addition, this new mixer will allow super homogeneous mixing for gaseous fuels with air according to different engine speeds. The new mixer has been designed such that the mixer can be easily connected with an Electronic Control Unit (ECU) for accurate control of the air–gaseous fuel ratio for different engine speeds. The methodology includes theoretical analysis, numerical analysis and experimental work to validate the results of the numerical study. In the numerical part, 14 models of mixers with 116 cases were computer simulated to investigate the effects on the homogeneity and distribution of the mixture according to diameter size, location, and number of holes. The performance of the new mixer models was studied using (ANSYS FLUENT) with different air–gas fuel ratios (six cases), using a fully open valve, and with an engine speed of 4000 rpm. The results of the simulation indicated that the lowest UI (uniformity index) values compared with other models were obtained for a gaseous fuel range between 0.651 an

In diesel—compressed natural gas (CNG) dual fuel systems, the CNG is generally inducted into the intake manifold by a CNG mixer mounted at the intake manifold, while the diesel fuel is directly injected into the engine cylinder using a diesel fuel injector system. The poor mixing performance of gaseous mixers is among the causes of unsatisfactory engine performance and lethal exhaust emissions. Based on an existing mixer model, four different models of mixers with 29 cases were created in this study to investigate the effects of the diameter, location, and number of holes inside the existing mixer on the homogeneity and distribution of the mixture. A computational fluid dynamics analysis software was used to check the flow behavior of the CNG and air inside the existing and new mixer models, with the new model being fixed on a 3.2 L engine. These models were examined depending on the maximum speed of the engine (4000 rpm), the full-opened valve, and the stoichiometric air–fuel ratio (34.6). Compared with the new mixer models, the existing mixer model shows a non-uniform methane and air distribution. Model 4/case 26 shows a uniform distribution of the CNG-air mixture with the best homogeneity. This model was then examined to check the flow characteristics of CNG and air at different engine speeds (1000, 2000, 3000, and 4000 rpm). Model 4/case 26 also shows a stoichiometric air–fuel ratio depending on the engine speed.