The effect of pressure, stand-off distance and time on the penetration of sandstones by a 0.84 mm. jet of water was investigated. Pressures ranged up to 9000 lb/in 2 (62 MN/M), stand-off distances to 2 in. (5.08 cm) and time from 0.5 to 30 sec. The effect of using a friction reducing agent was determined. The advantages of allowing the spent jet to escape and not interfere with penetration are ...

Removing devitalized tissue from chronic wounds through debridement is critical to promote wound healing. In this thesis, technology using high-speed water jets is explored toward applications for debridement. After presenting possible techniques, the thesis expands on one promising method using two impinging cutting jets that is further developed and demonstrated on simulated necrotic tissue. ...

The entrainment process in two-phase buoyant jets differs significantly from their singlephase counterparts, and is not well understood. Entrainment models developed for singlephase flow are often used in two-phase jetting simulations, albeit with limited success. In this work, Particle Image Velocimetry (PIV) and shadowgraph flow visualization experiments have been conducted on submerged round...

The ambient air is entrained intensively into atmospheric pressure thermal plasma jets. A system for shielding plasma jet has been used to improve jet characteristics and reduce oxygen content. Different gases have been applied as a shroud gas – argon, acetylene, methane, mixtures of acetylene-nitrogen and hydrogen-nitrogen. All shroud gases used in experiments affected plasma jet making the pr...

An idealized analytical model of the barotropic potential vorticity (PV) staircase is constructed, constrained by global conservation of absolute angular momentum, perfect homogenization of PV in mixing zones between (prograde) westerly jets, and the requirement of barotropic stability. An imposed functional relationship is also assumed between jet speed and latitudinal separation using a multi...

The removal of thick (approximately 1–10 mm) layers three viscoplastic soft-solid food-related materials (a moisturising cream, Biscoff spread and smooth peanut butter) from polymethylmethacrylate plates by turbulent, coherent, 2 mm diameter water jets was studied for jet velocities 10.6–25.4 m s −1 (10 500 < Re 25 400). When the layer thickness smaller than nozzle diameter, soil involved growt...

Self-propelled micro/nano-devices have been proved as powerful tools in various applications given their capability of both autonomous motion and on-demand task fulfilment. Tubular micro-jets stand out as an important member in the family of self-propelled micro/nano-devices and are widely explored with respect to their fabrication and functionalization. A few methods are currently available fo...