The technique of Computational fluid dynamics was applied to investigate flow field analysis including static pressure, axial, radial and tangintial velocities vectors as well as fluctuations of pressure analyses in axial pump. Pressure fluctuations are the core causes increase noise level and vibration. For studying pressure mechanism fluctuation in pump changed monitoring rotating points are stalled at an impeller blade. Standard k-epsilon turbulence model and sliding mesh technique are adopted by using CFD. The numerical investagation found that pressure in an axial flow pump rises near inlet impeller region to outer part. Higher value of pressure was take place at impeller outlet region. Also, the computational analysis noted that the when a pump functions in larger mass flow, the area of high-pressure in impeller outlet decreases. Moreover, under low flow rate (5 l/min) in middle surface the high-speed area appears near or closed blade and blade tip region for all velocities under investigations. Furthermore. fluctuations of pressure for different point under different flows has four valleys and peaks the similar number of axial impeller passages blades. The results foun that there are two imprtant regions the first one ispositive and second one is negative pressures, this happends owing to this negative pressure area has lower pressure value. Therefore, due to the decline in the water pressure in this area may cause cavitation.

Researchers are seeking alternative ways to deal with conventional fuels depletion and global warming. Biodiesel appears as one of the most candidate alternatives in this regard. The present work deals with biodiesel produced by transesterification of sunflower oil. The produced biodiesel was further mixed with kerosene to obtain a blend between new and traditional fuels. The physicochemical properties of the bio-fuel blended with kerosene have been tested in the laboratory maintaining different ASTM standards. In this study, blends of biodiesel and kerosene were tested on TQ small engine test set (TD200). BK60 (biodiesel 60 vol. % and kerosene 40 vol. %), BK45 (biodiesel 45 vol. % and kerosene 55 vol. %), BK30 (biodiesel 30 vol. % and kerosene 70 vol. %) and BK15 (biodiesel 15 vol. % and kerosene 85 vol. %) were tested. Three mixing speeds were used in the tests, namely; 1000 rpm, 2000 rpm, and 3000 rpm at constant high load of 80%. The performance parameters studied included; brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC). Regarding the emissions, carbon monoxide (CO), hydrocarbons (HC), and oxides of nitrogen (NOx) were also recorded. Results showed that the new blends produce higher BTE and lower BSFC than the conventional kerosene and biodiesel.

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One of the major problems in the contemporary world is pollution. The major contribution in this area comes from automobile emissions and industries. Diesel being one of the major fuels is also a major contributor in adding harmful pollutants into the atmosphere. In order to meet the stringent emission norms, the polluting components in the fuels need considerable reduction. Fuel characteristics play a major role in engine efficiency and engine emissions directly or indirectly. In the present work, an experimental investigation of the effect of adding methanol to the diesel-biodiesel blends on the performance and combustion characteristics of the diesel engine has been performed. Three different concentrations of methanol are used; namely 5%, 7%, and 10% of the overall mixture volume, while, biodiesel concentration has been fixed to eliminate its effect on the results. The results revealed that using methanol as an additive to the diesel-biodiesel blends prominently improved brake power, decreased brake specific fuel consumption (BSFC) and increased brake thermal efficiency (BTE) of the engine. CO, HC, and NOx emissions have shown a slight decrease compared to the corresponding neat diesel and diesel-biodiesel at the same loading and engine speed conditions.

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