2 research outputs found
HERMITE NUMERICAL METHOD TO ESTIMATE THE RADON AND RADIUM EFFECTS OF THE SOIL IN BARTELLA REGION
The Hermite numerical interpolation method used to estimate and predict the radon and radium concentrations, from some of the experimental measurements made on the soil samples of the Bartella region in Iraq. The results obtained from deductible mathematical method were close to real experimental results. Predicted results are in the range of 80.04–4051.59 Bq/m3radon concentrations and 0.322–17.276 Bq/Kgradium concentrations corresponding to 200-10000 tracks of alpha particles. The maximum errors were less than 0.289 and 1.172 percent for radon and radium concentrations, respectively. The effects of radium and radon radiations estimated of soil in the studied area depend on its concentrations, a higher number of alpha particle tracks mean high radiation concentration, the high radiation will cause human health damage. The values are below 370 Bq/Kg the recommended radium concentration permissible values, by the Organization ащк Economic Cooperation and Development (OECD), the studied area is safe from hazards on health of radium and radon exposure from the soi
PARAMETERS EFFECTS ON CONDUCTION-CONVECTION HEAT TRANSFER IN RECTANGULAR ENCLOSURE SANDWICHED BY FINITE THICKNESS WALLS
The effect of wall heat conduction on natural convection heat transfer in cavities has gained attention of many researchers in recent years due to its wide application areas in engineering such that building heating and cooling and thick enclosures , etc . In this work , we consider a two-dimensional numerical study of a rectangle cavity filled with an air with two vertical conductive walls of finite thickness . The enclosure is subjected to horizontal temperature gradient , the vertical boundaries are isothermal at different temperatures whereas the remaining walls are adiabatic .The theoretical study involved the numerical solution of the Navier-stokes and energy equations by using finite difference method . The stream-vorticity formulation was used in the mathematical model . The physical problem depends on five parameters : Rayleigh number (1000<Ra<1000000) , the Prandtl number (Pr=0.7) , the wall to fluid thermal conductivity ratio (0.1<=Kr<=10) , solid to fluid thickness ratio (0.5<=L1/L2<=1.5) , the ratio of (left or right) solid thickness to the height )(D=L1/H=0.5,0.6667,0.75) and the aspect ratio (H/L= 0.5,1,1.5) . The main focus of the study is on examining the effect of conduction in the wall on the natural convection flow .The results are presented to show the effect of these parameters on the heat transfer and fluid flow characteristics