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Full-Text Articles in Atmospheric Sciences
Design Of A Small Scale Wind Generator For Low Wind Speed Areas, Ra Msuya, Rrm Kainkwa, Mi Mgwatu
Design Of A Small Scale Wind Generator For Low Wind Speed Areas, Ra Msuya, Rrm Kainkwa, Mi Mgwatu
Tanzania Journal of Science
Most small scale level wind turbine generators are directly driven system, variable speed, and partially connected power electronic converter system. Choice of such system is to avoid costs associated with gearbox. However, due to low wind speed in most of the tropical countries, synchronous generators with smaller or medium speed Permanent Magnet (PM) generator design found to be important and given high performance efficiency. In order to be able to harvest wind energy in off-grid population efficiently, there was a need to design a synchronous generator that can be able to operate under low wind speed, directly connected to the …
Prediction Of Rainfall In The Southern Highlands Of Tanzania, Pasvolo Mwinuka, Christian Uiso
Prediction Of Rainfall In The Southern Highlands Of Tanzania, Pasvolo Mwinuka, Christian Uiso
Tanzania Journal of Science
Previous studies on the variability of March to May (MAM) and October to December (OND) rainfall in East Africa have mainly covered the whole region without considering the local climate zones such as the Southern Highlands of Tanzania. Results from the regional studies have shown that the Indian Ocean Dipole (IOD) and Outgoing Longwave Radiation (OLR) have strong association with OND rainfall and weak one with MAM rainfall in East Africa. The present study was aimed at determining the potential predictors for the MAM and OND rainfall by considering IOD, El Ni o Southern Oscillation (ENSO), Quasi-biennial Oscillation (QBOu30 and …
Comparison Of Accuracies In Techniques For Evaluating Wind Power Density, Reuben Kainkwa, John Kumwenda
Comparison Of Accuracies In Techniques For Evaluating Wind Power Density, Reuben Kainkwa, John Kumwenda
Tanzania Journal of Science
Wind power is among important renewable sources of energy. In order to know the magnitude of wind power, appropriate techniques for evaluating it need to be investigated. Apart from the standard formula that can be used to evaluate wind power density at a site there are two more techniques namely power law exponent and Weibull two-parameter density function. However the accuracy of the latter two methods relative to the standard one has not yet been investigated. The main objective of this paper is to compare accuracies of these techniques. The wind power densities were calculated using standard formula, Weibull model …
Luminous Transmittance And Phase Transition Temperature Of Vo2:Ce Thin Films Prepared By Dc Reactive Magnetron Sputtering, S Ambonisye, M E Samiji, N R Mlyuka
Luminous Transmittance And Phase Transition Temperature Of Vo2:Ce Thin Films Prepared By Dc Reactive Magnetron Sputtering, S Ambonisye, M E Samiji, N R Mlyuka
Tanzania Journal of Science
Vanadium dioxide (VO2) and cerium-doped vanadium dioxide (VO2:Ce) thin films were prepared by DC reactive magnetron sputtering from vanadium metallic target and V-Ce alloy targets. Luminous transmittance and phase transition temperatures of the films were studied. The Shimadzu SOLIDSPEC-3700 DUV-VIS-NIR spectrophotometer was used to measure the transmittance and reflectance of the films. The phase transition temperature (τc) of the films was obtained from both the transmittance and sheet resistance against temperature curves. A change in sheet resistance of 2 to 3 orders of magnitude was observed for both undoped and Ce-doped VO2 films. Comparison between undoped and doped VO2 films …
Survey Of Wind Power Potential For Wind-Based Electricity At Makambako, Iringa Tanzania, Rmr Kainkwa
Survey Of Wind Power Potential For Wind-Based Electricity At Makambako, Iringa Tanzania, Rmr Kainkwa
Tanzania Journal of Science
The potential for wind-generated electricity is examined using 22 months wind data collected from a prospective site located in the southern highlands of Tanzania. While the data for the year 2001 was from March to December that of 2002 was for all the twelve months of the year.Characteristics of monthly and annual wind speed and direction are systematically investigated based on hourly time-series data using Windographer software. The Weibull shape factors k corresponding to a height of 50 m were found to be 3.10 and 3.80 while the scale factors c were 11.06 and 12.27 m/s for the years 2001 …
Assessment Of Wind Energy Potential For Eletricity Generation In Setchet, Hanang, Tanzania, A. S. Kasasi, R. M. Kainkwa
Assessment Of Wind Energy Potential For Eletricity Generation In Setchet, Hanang, Tanzania, A. S. Kasasi, R. M. Kainkwa
Tanzania Journal of Science
Tanzania depends heavily on hydropower for her electricity demand and experiences power shortage during the dry seasons. Wind energy is proposed as an alternative source of electricity to the fossil fuel generators during the dry season, the latter are normally used to supplement the shortfall in hydro-electricity generation. Fossil fuel generators produce emissions that are toxic and as such degrade the environment. Wind speed data from a site called Setchet is used to illustrate that the available wind energy can be harvested to generate electricity that can supplement the shortfall of electricity. The windy season, which is from July to …