446
CHAPTER 7. LABORATORY WAVE GENERATION
waves by pneumatic wave generators (similar to wavemakers used in large
recreational wave pools). This type of wavemaker has a chamber with a
nozzle-like connection to the wave flume. The connection is located well
below the still water line. Increasing the air pressure within the chamber
causes the chamber water level to decrease. This forces mass flow out of
the nozzle into the wave flume, which in turn generates a progressive water
wave. Similarly, decreasing the chamber air pressure increases the chamber
water level, which draws water back into the chamber from the wave tank.
Of course, oscillating changes in air pressure generates oscillatory waves.
See Keulegan (1966) for additional details and an example design for a
single-surge tsunami generator.
Finally, theories have also been developed for wavemakers having porous
wave boards (Chwang 1983, Huang 1989), but they have seen little use in
practice.
CHAPTER 7. LABORATORY WAVE GENERATION
waves by pneumatic wave generators (similar to wavemakers used in large
recreational wave pools). This type of wavemaker has a chamber with a
nozzle-like connection to the wave flume. The connection is located well
below the still water line. Increasing the air pressure within the chamber
causes the chamber water level to decrease. This forces mass flow out of
the nozzle into the wave flume, which in turn generates a progressive water
wave. Similarly, decreasing the chamber air pressure increases the chamber
water level, which draws water back into the chamber from the wave tank.
Of course, oscillating changes in air pressure generates oscillatory waves.
See Keulegan (1966) for additional details and an example design for a
single-surge tsunami generator.
Finally, theories have also been developed for wavemakers having porous
wave boards (Chwang 1983, Huang 1989), but they have seen little use in
practice.