I am a mechanical and nuclear engineer, specialized in thermodynamics and fluid mechanics simulations. I was a research engineer in a nuclear research institute in Sao Paulo, Brazil from, 1977 until retirement in 2010. Developed software for thermodynamic simulation of thermal energy systems and its components, using Scilab software The theory and open source software of GitHub address, for the design of the following : 1- centrifugal pumps, 2- fire tube boilers, 3- cooling towers, and 4- Fresnel linear reflector, using Newton Raphson method by Scilab 6.0.2 are shown in the blogs in the following site https://wsbassel.wordpress.com/