In general, hydrocodes provide us with information that we cannot get from actual physical tests in the HVIT lab. These are some of special problems that can be solved using hydrocodes and how the results can be used to design better meteoroid and debris shields for spacecrafts.
We can perform testing at velocities too high to obtain experimentally. Meteoroids follow interplanetary orbits around the Sun, attaining velocities of up to 42 km/s (for highly elliptical orbits intersecting the Earth's). If you add the 30 km/s orbital velocity of the Earth, meteoroids can attain a theoretical maximum impact velocity of about 72 km/s with a spacecraft in Earth orbit.
Man-made orbital debris follow terrestrial orbits and can impact a spacecraft head on in low Earth orbit at a velocity of 15 km/s. These impact velocities can not be achieved in a laboratory, however they can be modeled using hydrocodes.
In the lab, we launch spheres and cylinders, but actual debris is not so conveniently shaped. Shape is important, and it is difficult to launch shapes other than spheres and cylinders. Hydrocodes can provide information about pressures, temperatures, stresses, strains, entropy, and other parameters, of any point in the model, at any instant (discreet timestep) during the impact event.