A simple and efficient levitation technique for noncontact coating of inertial confinement fusion targets

K K MISHRA, R K KHARDEKAR, RASHMI CHOUHAN and R K GUPTA

Laser Fusion Target Laboratory, Centre for Advanced Technology, Indore 452 013, India

Abstract.

A simple and very efficient gas jet levitation technique for levitating inertial confinement fusion (ICF) targets has been developed. A low velocity gas jet through diverging nozzle generates precisely controlled low Reynolds number flow pattern, capable of levitating polymer microballoons up to 2500 mm diameter. Different shaped diverging nozzle are investigated, satisfactory levitation is achieved with simple conical shapes. With this setup microballoon can be levitated for hours with excellent stability, continuous rotation and at the desired height (reproducible with in less than 100 m m). The height of stabilization depends upon cone angle of diverging nozzle and velocity of levitating gas. This technique is very robust and highly insensitive to external disturbances like nonuniform temperature fields and vibrations. This setup is very economical to fabricate, easy to operate and can be used efficiently in various spray coating application involving plastic and metallic layers on microballoons.

Keywords: Inertial confinement fusion targets; low Reynolds number levitation; fluid dynamics.

Pacs No. 47.52.+j; 05.45.Gg; 52.35.Py; 47.20.-k; 52.40.Nk