Direct numerical simulations are carried out to investigate the role of the turbulent region in a self-sustaining system with a spiral vortex structure in the three-dimensional boundary layer over a rotating disk by solving the full Navier–Stokes equations. Two computational domains with two different azimuthal sizes, $2\unicode[STIX]{x03C0}/68$ and $2\unicode[STIX]{x03C0}/32$, are used to deal with different initially dominant wavenumbers. An artificial disturbance is introduced by short-duration strong suction and blowing on the disk surface. After the flow field reaches a steady state, a turbulent region forms downstream of $Re=640$. The turbulent region is then removed using two methods: a sponge region, and application of a slip condition at the wall. In both cases, the turbulent region disappears, leaving the spiral vortex structure upstream unaffected. The results suggest that the downstream turbulent region is not related to the velocity fluctuations that grow by the global instability. In addition, when the area where the slip condition is applied is changed from $Re>630$ to $Re>610$, the velocity fluctuations decay. The results indicate that the vibration source of the velocity fluctuations which grow by the global instability is located between $Re=611$ and $Re=630$.

The wavelength scalings of soft X-ray and hot electron generation efficiencies were studied using 1·05, 0·53, 0·35 and 0·26 μm lasers. A coupling efficiency from absorbed laser energy to compressed fuel core of 4.5% was obtained by using the GEKKO XII green laser.

This paper deals with a lithium/tin combined target to increase the conversion efficiency of extreme ultraviolet (EUV) of 13.5 nm emission from laser-produced plasma. The bilayer target of glass/lithium (20 nm)/tin (50 nm) exhibits a sharp and strong emission in comparison with a Sn bulk target. The reverse coating of glass/tin/lithium was unstable and EUV could not be observed. By using nano-porous SnO2 and an electrochemical deposition of lithium, nano-structured lithium/tin composite was prepared, and was stable without deliquescence of lithium.

Low density foam shells with high optical transmittance for fuel targets for the coming upgrade laser systems were developed by increasing the polymerization initiator for trimethylolpropane trimethacrylate in an oil phase of a water/oil/water emulsion. Foam with similar performance was fabricated using reduction-oxidation polymerization of ethyleneglycol dimethacrylate. These results showed that a cryogenic fuel layer sustained by these foam layers can be charecterized using optical interference technique.