Biomedical Engineering Reference
In-Depth Information
this device can be found in Figure 8. Little additional information is currently
available on these types of devices.
A third device explored is pneumatic pipe-guns for plasma fueling. These
are developed for the purpose of delivering fuel pellets to devices such as
experimental fusion reactors (Viniar and Sudo, 1996). The diameter of the
deuterium fuel pellets in this case is 3mm, and these pellets are accelerated to
1200 m/s using helium gas. Because of the nature of the deuterium pellets and
the cryogenic temperatures required to keep the pellets in the solid state, this
device consists of many complex parts unnecessary for purposes of this study.
However, this particular device was studied to determine the basic operating
principle, including the type of valves used to release the helium gas.
Unfortunately, little was mentioned about this valve other than the opening
time of approximately 1 ms (Viniar and Sudo, 1996). Several different types of
these devices exist for the same purpose. Another pneumatic injector has been
developed by ENEA Frascati (Frattolio et al., 1999). This device operates in
two stages, using hydrogen as the propellant gas. Speeds of up to 2500 m/s
have been achieved with particles ranging in size up to 6 mm (Frattolio et al.,
1999). This device also makes use of ―fast valves‖, which is discussed in the
following section. An illustration of this pneumatic gun is shown below in
Figure 9.
Reproduced with permission. Copyright retained by Inderscience Publishers.
Figure 9. Illustration of pneumatic gun developed at ENEA Frascati (Frattolio et al.,
1999).
Existing methods of measuring speeds of particles fired form devices are
explored. Fukunama et al. (2006) utilize a DPV-2000 system to measure
velocity of in-flight particles from a cold spray device. The system is based on
sensing reflection from a laser aiming at the particle stream. A mask is placed
in front of the sensor with two slits, and velocity is determined by measuring
