Introduction For several years, Quality Function Deployment (QFD) has been at the leading edge of research and development in many fields (Barnett and Raja, 1995; Chiou and Tong, 2001; Han et al., 2001; Pitman et al., 1996; Pramod et al., 2007; Walker, 2002; Wang, 2007). QFD evolved as a way to incorporate knowledge about the needs and desires of end-user customers into all stages of the design, manufacture, delivery and support of products and services (Einspruch, 1996; Griffin and. Hauser, ...
Abstract: Adsorption refrigeration technology has been intensively investigated in many countries of the world because of its promising potential for competing with conventional vapour compression refrigeration, its relatively low operating cost and its environmental friendliness. The search for a good adsorbent for solar powered refrigeration technology has led to various attempts to manufacture activated carbon of high adsorptive property. In this study coconut shells plus 10% animal bones...
Abstract This paper presents experimental and simulation study of the effects of stress on microstructure and failure morphology of low carbon steel under plane stress conditions. The study has revealed large extension of grains at the point of fracture and, stress and strain looped around the pearlitic faces of the microstructure matrix. The stress and strain distributions in the microstructure have shown that concentration of stress and strain on the pearlite were instrumental to oblique f...
Abstract A pressure perturbation technique based on a simple adaptation of the Weirtheim's first order thermodynamic perturbation theory has been developed and used to formulate a generalized equation of state. The practical equation formulated was applied to pure fluids, binary systems and real samples of Niger Delta Petroleum fluids. Tuning of data is not required. The results show more accurate predictions than the commonly used SRK and PR equations This work provides a theoretical framew...
ABSTRACT The broad objective of this research was to recover exhaust gases thermal energy from internal combustion engines for use in other applications. The specific objectives were: to determine the amount of thermal energy lost through exhaust gases at various engine speeds and loads; to determine the amount of energy recovered from exhaust gases at various engine speeds and loads; and to simulate the amount of maize that could be dried with the recovered energy. The experimental set-up c...
ABSTRACT Producing enough food in Kenya to better feed people and generate adequate income for the farmers is a great challenge. This challenge is likely to intensity, with a population that is projected to increase to 66.3 million in 2030. Scarce water resources and growing competition for water will be reduce its availability for irrigation, which necessitating major changes in irrigation management and scheduling in order to increase the efficiency of use of water that is allocated to agr...
ABSTRACT The conversion of forest land to agricultural land and urban settlement usually increases soil erosion, and volume of storm runoff in a catchment. In Kenya, the rural communities are encroaching into the humid and marginal areas to open up new lands for agricultural production and settlement. These changes have led to environmental degradation, which has negatively altered the hydrologic regimes of many catchments in Kenya. The Wundanyi River catchment is one of the catchments that ...
ABSTRACT The availability of egg products for consumption is hindered by spoilage and breakages during processing. Forced convection drying serves as one of the methods of solving these challenges. However, the influence of temperature, airflow rate and slice thickness on forced convection drying of eggs is inadequately documented. Therefore, drying of eggs was investigated under forced convection process. The mode of airflow and the food material was the continuous concurrent type. Raw eggs...
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 Reservoir oil viscosity is important in understanding reservoir flow behaviour, l facilities design and sizing and in the computation of recovery performance, well' productivity and lift requirements. Direct viscosity measurements are expensive or sometimes unavailable hence empirical correlations are often used for predictions. However, several published correlations are either too simplistic or complex for routine operational use and improved methods continue to receive attention....
ABSTRACT Most stoves based on the principle of micro gasification have improved thermal efficiencies with low emissions, however, knowledge on the effect of the stove operation at different air flow rates on thermal efficiency, fire power, emissions, specific fuel consumption and burning rate is scarce. The main objective of this research was to evaluate performance a micro gasifier cook stove. An experimental forced draft cook stove was therefore developed using the available materials base...
ABSTRACT Bottom-hole pressures in gas and condensate wells are frequently measured at a great cost and with operational challenges. On the other hand, most analytical estimation procedures either use trial and error or neglect liquid holdup in condensate wells. Using the mechanical energy balance approach, an approximate model was developed to estimate bottom-hole pressure from wellhead pressures in condensate wells without neglecting liquid holdup. The results show that treating gas condensa...
ABSTRACT We report the development of a predictive model based on artificial neural network (ANN) for the estimation of flank and nose wear of uncoated carbide inserts during orthogonal turning of NST (Nigerian steel) 37.2. Turning experiments were conducted at different cutting conditions on a M300 Harrison lathe using Sandvic Coromant uncoated carbide inserts with ISO designations SNMA 120406 using full factorial design. Cutting speed (v), feed rate (f), depth of cut (d), spindle power (...
ABSTRACT Sorghum threshing in Kenya is characterized by high grain breakages and accounts for grain loss of 4% of total production. Existing threshing methods are time consuming and yield a low throughput. Grain losses mainly occur due to grain damage and incomplete removal of grains from panicles. In order to reduce the losses, optimal levels of machine and operational parameters influencing threshing need to be established. A prototype spike tooth sorghum thresher was therefore developed u...
ABSTRACT Refractory bricks (refractories) are used in the construction of furnaces and kiln internal linings that hold, melt and transfer raw materials being processed. Kenya imports refractories mainly for its cement, metal smelting and sugar processing industries. Kaolin, bauxite, salama, soapstone and ball clays exhibited Loss of Ignition of 7-15%, silica of 46-55% and alumina of 25-34%. Soapstone and salama clays exhibited high values of potassium (5.6%) and iron oxide (16%), while salam...