Fluid blade to help US troops in Afghanistan

A device developed by Sandia National Laboratories researchers that shoots a blade of water capable of penetrating steel is headed to US troops in Afghanistan to help them disable deadly improvised explosive devices (IEDs) - the number one killer and threat to troops in Afghanistan, according to the Pentagon.

“The fluid blade disablement tool will be extremely useful to defeat IEDs because it penetrates the IED extremely effectively,” said Greg Scharrer, Manager of the Energetic Systems Research Department at Sandia. “It’s like having a much stronger and much sharper knife.”

The fluid blade disablement tool was invented by Steve Todd, a mechanical and materials engineer with extensive Navy experience fighting IEDs; Chance Hughs, a retired Navy SEAL explosives expert on contract to Sandia; and mechanical engineer Juan Carlos Jakaboski in Sandia’s Energetic Systems Research Department.

The portable clear plastic device is filled with water and an explosive material is placed in it that, when detonated, creates a shock wave that travels through the water and accelerates it inward into a concave opening, Todd said. Therefore, when the water collides, it produces a thin blade.

“That allows you to have a high-speed, very precise water blade to go through and do precision type of destruction on whatever improvised explosive device it’s going up against. Immediately behind the precision water blade is a water slug, which performs a general disruption that tears everything apart,” Todd said.

Unlike traditional explosives, which release energy equally in all directions when they go off, researchers use shaped-charge technology to deliberately manipulate the explosives so that they create a certain shape when they explode, allowing the operator to focus the energy precisely where it’s needed. The inventors of the fluid blade disablement tool took a different tack. Rather than changing the shape of the explosive, Todd, Hughs and Jakaboski used an explosive modelling tool to figure out how to change the shape of the water when designing the water disruptors.

“We’re putting the explosive in a flat tray and we’re shaping the water,” Scharrer said.

The process happens in microseconds and can’t be captured by the human eye, so researchers used computer simulation and high-speed flash X-rays, which can view the interior of imploding high-explosive devices and record the motion of materials moving at ultrahigh speeds, to finetune the design.

Paul Reynolds, TEAM Technologies’ Program Manager, said the company improved the tool based on the soldiers’ input after it was exposed to dust, water and banging around by the troops. The improvements included providing a better seal and redesigning the water plug so it is easier to insert.

“The soldiers helped on the design to make it more ruggedised and small enough,” Todd said. “It was a very good collaboration.”