Many researchers have conducted extensive experimental and numerical studies to explore the influences of multiple types of fuels. The high demand of energy in the world has led to the growing crisis and depletion of fossil fuels. Therefore, the researchers have focused on investigating renewable energy sources like biodiesel with the aim of suggesting, which energy is more friendly to the environment. Biodiesel has specifications for using it as an alternative fuel to traditional fossil fuels. Whereas, the use of biodiesel fuel in the original design of Diesel engine can emit a higher percentage of nitrogen oxides (NOx). Therefore, to reduce the harmful emissions of the fuel, the injection schemes and injector nozzle bore (INB) of the engine were modified. The present research combines the effect of the nozzle hole diameters and split injection scheme on the performance and combustion parameters of compression ignition (CI) engine was investigated. The engine was fueled with diesel blended of different proportions (Sp20, Sp40, Sp60, and Sp100) of spirulina biodiesel to prove the suitability of this blend as an alternative fuel. The injector nozzle has three injection holes, and the diameter of the three modified holes of the nozzle is changing (from 0.20 to 0.28 mm, step 0.02 mm) along with two types of scheme injection (double and triple). Furthermore, the influence of the direct injection Diesel‐RK model, single‐cylinder, four‐stroke engine; constant compression ratio (17.5:1), engine speed (1500 rpm), and naturally aspired engine at full load condition are studied. A comparison of the present simulation is compared with published results to validate the present simulation model for conventional baseline Diesel for validation. The simulation was done to investigate and present a comparative study with the conventional baseline Diesel engine. The double injection scheme shows a decrease by 1.8%, 1.7%, and 1.9% for parameters of peak cylinder pressure (PCP), peak cylinder temperature (PCT), and maximum rate of pressure rise, respectively. Whereas, the specific fuel consumption (SFC) and break thermal efficiency are increased by 8.7% and 9.33%, respectively. The results showed a reduction by 2.1%, 20.5%, 22.1%, and 3.2% in PCP, PCT, maximum rate of pressure rise, and break thermal efficiency, respectively. Moreover, the SFC is increased by 3.1% with the modified INB 0.28 (mm).

Although many fluidized systems are not vertically oriented, little research has been done on fluidization within inclined channels. The fluidization of the gravitational force and the tensile force may be substantially opposing in the vertical system. The theory of gravitational field fluidization, which is related to industrial fluidization processes like coal gasification, iron ore reduction, and catalytic cracking and calls for the use of standing tubes or angled risers, has to be developed in order to encompass various orientations. Without underlying theories, engineers must rely on vertical fluidization equations to build these sloping systems. A significant barrier to improving the design and optimization of new solid circulation systems is the tendency of fluidization. Based on historical developments and theoretical progress, the study presents an overview of recent advancements of liquid-solid fluidized beds in inclined columns. The fluidized bed is investigated as a whole by looking at the governing factors.

Unsustainable fossil fuels are mainly used to generate power in compression ignition (CI) engines in industry now. Due to fossil fuel depletion and potential environmental hazards, it is necessary for researchers to find alternative energy resources to adequately substitute hydrocarbon fossil fuels in current engines. A huge number of studies have focused on the use of renewable fuels in CI engines along with conventional petroleum fuels. Therefore, this paper aimed to analyze the effect of gaseous fuels added to CI engines as a supplement, such as H 2 , biogas and syngas, in dual fuel mode with diesel as an alternative fuel. This paper analyzed several important characteristics, on which engine evaluation of CI engines using gaseous fuel as an additive is based, such as combustion, performance and emissions, and compared them with those of CI engines operating in single-fuel mode. The findings of numerous empirical studies are shown in graphs of particular parameters, which were crucial for investigating and assessing the case. The main conclusions indicated that gaseous fuel enrichment caused slight decline of performance in CI dual-fuel engine but actually improved emissions. In addition, this paper thoroughly analyzed various methods to assess the performance of biogas in CI dual-fuel engines and investigated dangerous emission pollution.

In this study, the combined effect of the piston bowl geometry and fuel injection pressures on combustion, performance and emission characteristics of compression ignition (CI) engine fueled with baseline Diesel (D100) and microalgae-biodiesel (MA100) was studied. In this paper, the comparison study for the two different piston bowl geometry, namely: hemispherical combustion chamber (HCC) and toroidal re-entrant combustion chamber (TRCC), was carried out with the various fuel injection pressures (200-240 bar) performed. A single-cylinder, direct injection, and four strokes were chosen to simulate the compression ignition (CI) engine by developing a zero-dimensional simulation model using Diesel-RK commercial software. The data was validated by comparing the results against experimental data, which showed that the results obtained from the numerical simulation were in good agreement with the experimental results. MPRR, EGT, HRR, BTE, and NOx exhibited an increase with increased fuel injection pressure, while an inverse trend was observed with ID, CO, and HC. When using MA100 biodiesel with HCC piston bowl geometry at fuel injection pressure (200 bar), the maximum predicted brake specific fuel consumption (BSFC) was 0.545 kg/kWh. A significant reduction of nitrogen (NOx) oxides emissions was also observed with low fuel injection pressures. In contrast, the emission characteristics such as hydrocarbons and CO were enhanced by increasing fuel injection pressure and modifying the piston bowl geometry.

In this paper, a micro pin fin heat sink is numerically investigated with four fins geometries (circular, elliptical, square, and drop shape) at two types of arrangement styles, inline and staggered arrangement. The hydrodynamic and thermal characteristics of different fin geometries and two arrangement styles have been compared under the exact value of Reynolds number and constant wall temperature thermal boundary conditions. The Reynolds number was sweeping in the range of (400-2800) to ensure the fluid flow velocity impact in the pin fin performance. The results obtained indicate that a longitude pin fin dropped with increasing Reynolds number at a distributed temperature. Also, the circler Pin fin reaches the lowest temperature comparison to the rest of the three-pin fin types. Generally, according to the extracted, Nusselt number for different geometries increased versus increasing the Reynolds number. Observe that the elliptical fin shape yields the highest Nusselt number at all Reynolds numbers. Moreover, the elliptical pin fin ejects the highest heat transfer rate, which indicates the pin fin performance. Furthermore, skin friction has a significant function with variation in Reynolds number.