There is a huge requirement for development of a coating technique in nuclear industry, which is environmentally safe, economical and applicable to large scale components.  In this view, simulation of gas-phase   behavior in specially designed CVD reactor was carried out using computational tool, COMSOL. There were   two important zones in CVD   reactor first one is precursor vaporization zone and second   one is coating zone. Optimized parameters for coating were derived from the simulation of gas phase dynamics in both zone of CVD reactor. The overall effect of fluid velocity, heat flow and concentration profile showed that Re = 54 is the optimum reaction condition for uniform coating in CVD system. In CVD coating experiments a synthesized halogen free, non-toxic and non-corrosive silicon carbide precursor was used. Uniform coating of SiC was obtained on zircaloy substrate at 900°C using as synthesized organosilicon precursor. The X-ray diffraction and scanning electron microscopy analysis show that dense nano crystalline SiC film was deposited on zircaloy substrate.