2 research outputs found
Assessment of solar energy source distribution and potential in Zambia
Zambia is vastly endowed with a wide range of energy resources. Yet, to date, Zambia has not fully exploited its potential in solar energy utilisation for electricity generation due to various reasons such as lack of understanding of the distribution of solar energy potential in the country and limitation of access to solar energy resource information. This paper assess the solar energy distribution and potential in Zambia. Nine provinces with different geographical and climatic regions that makes up Zambia were assesed. The distribution of solar radiation within the country were assessed using spatial analysis in ArcGIS Software. The 22year period solar datasets were considered for assessment. These datasets were obtained from NASA Atmospheric Science Data Center using Surface Meteorology and Solar Energy. The analyzed results indicate that Zambia has approximately 20,442TWh/year technical solar energy potential and receives 2109.97kWh/m2 of solar energy per year with 4403.12hours of sunshine. The country has 186,121km2 available and suitable land area for RETs implementations. This study is important as it present an overview of the technical solar energy potential for Zambia which is vital for decision making, energy mix and sustainable deployment of solar energy technologies in the countr
Oxygen enrichment effects on CH 4 -air turbulent flow characteristics in a coaxial swirl burner
International audienceThis paper reports results on the effect of oxygen enrichment on flow and turbulent flames in a coaxial swirl burner. The investigation was performed by S-PIV in CH4-air-O2 non-reacting and reacting flows. This work is the continuation of studies carried out previously by the authors on the same burner, with different new operating conditions. The burner consists of 2 concentric tubes, with a swirler located in the annular part through which the oxidant (air-O2) is supplied. The CH4 gas is delivered into the central tube and injected radially into the combustion chamber through small holes. The burner is placed in a parallelepiped combustion chamber with a volume of 120×50×50 cm3. The paper reports detailed results on mean velocity fields, profiles of the three velocity components (U,V,W) and velocity fluctuations (U’,V’,W’) in the case of a 150 Nl/min oxidant flow rate, a swirl number Sn = 1.4 and an equivalence ratio Φ = 1. Three cases of O2 addition were investigated, 21%, 25%, and 30% (in vol.) corresponding to 9.4 kW, 11.7 kW, and 14.5 kW of combustion power, respectively. In-depth analysis of the field velocity differences between reactive and non-reactive cases was carried out and showed a significant difference in flow velocities between reacting and non-reacting flows. The profiles of the mean velocities, fluctuations and velocity decays differed, and higher values were observed in the reacting case. The enrichment of air with oxygen affected the velocity fields and their fluctuations in both distribution and values. The addition of O2 increased the flame temperature, leading to a greater radial expansion and a reduction in the size of the recirculation zone. The maximum axial velocity increased significantly as a function of the O2 rate, whereas the swirling velocity varied only slightly. The velocity fluctuation results also revealed a difference in profiles and values depending on O2 enrichments and locations along the flow