ABSTRACT Forced convection grain dryers are more efficient and achieve greater drying rates than natural convection dryers. However, it is necessary to provide an appropriate solar air heater in order to achieve the required drying air temperature. Well sized fan and drying cabinet, as well as an optimal combination of air velocity, temperature and grain layer thickness are also essential for improved performance of such a dryer. In order to predict variation of moisture content with time dur...
ABSTRACT Environmental pollution caused by the Municipal Solid Waste (MSW) incinerators has raised concerns about the quality of incinerators and the incineration process in Tanzania. Engineers and Scientists in general have appreciated that the installation of functional incinerators will increase the incineration process efficiency. Among the methods to achieve this is the application of mathematical modeling for the incineration process. Literatures have showed that related study in i...
ABSTRACT The dynamic simulation is one of the key steps in the validation of the design process of the motor drive systems and it is needed for eliminating inadvertent design mistakes and the resulting error in the prototype construction and testing. A quality mathematical model of induction machine based on the dynamic equations and D-Q transformation technique is presented in rotor reference frame and a computer simulation of a 7.5kW three phase induction motor was carried out based on thi...
Abstract This research presents the results of numerical study of heat transfer and pressure drop behavior in a compact heat exchanger (CHE) designed with drop-shaped pin fins. The heat exchanger used for thisresearch consists of a rectangular duct fitted with different drop-shaped pin fins dimensions with the same heat transfer wetted surface area.A three dimensional finite volume based numerical model using ANSYS FLUENT 14.5 has been conducted to select the optimum pin fin dimension conside...
ABSTRACT In this research the thermal reactors have been studied, we reviewed the history of thermal reactors focusing on comparing advantages and disadvantages of using of each thermal reactors class, accordingly to these classification. we choose the pressure water reactor as the best candidate of these thermal reactors, this is due to the isolations of the second vapor cycle from the pressure and vapor system in the first cycle. This enable the pressure water reactors to be the most stabl...
ABSTRACT Poor vehicle maintenance culture and high proportions of old vehicles are major contributing factors to high vehicle emission levels. The purpose of this study was to determine performance and emission characteristics of vehicles that were taken for inspection at the Vehicle Inspection Centre in Nairobi City based on engine operating parameters and to develop performance and emission prediction models. The specific objectives were; to determine vehicle exhaust emission levels, engin...
ABSTRACT The recent power sector reform in Nigeria has thrown up enormous challenges in this sector, ranging from the construction of more power stations, construction of new transmission lines and substations. The existing network of 8-plants and 26 bus-bars expanded to the proposed network of 16 generating plants with 49 bus-bars. This network expansion requires reappraisal for power evacuation capabilities, relay systems setting and establishment of stability margins for adverse system f...