Matrix Games Forums

Convergence zones....I have read the manual but still have trouble understanding what they are and how they impact me in game play. In the map information box it will say something like CZ: 32-64-96-128. These must be miles and seem to correspond with the shaded circle surrounding my Subs. I just don't understand what these are showing me. Just a small definition or explanation would be much appreciated.

http://www.fas.org/man/dod-101/navy/doc ... r_prop.htm

Read the part with Figure 14 and 15. That should help a bit.

I don't understand Figure 6. My understanding is that colder water is more dense, therefore the speed of sound should be faster in colder (deeper) water. However, Figure 6 seems to indicate the opposite.

What am I missing here?

ORIGINAL: Colonel Mustard

I don't understand Figure 6. My understanding is that colder water is more dense, therefore the speed of sound should be faster in colder (deeper) water. However, Figure 6 seems to indicate the opposite.

What am I missing here?

There is another effect also, in that in warmer water the average speed of molecules are higher and hence they propagate pressure waves quicker. If I remember correctly, the increase due to temperature and decrease due to warmer water expanding works out to sound having the fastest speed in water (at 1 atm) when the water is about 75C.

I don't remember how this all works out when the pressure increases also, but I suspect it is this effect that makes the counter-intuitive Figure 6.

The convergence zones (CZ) are formed only in deep water.
This is because sound rays refract towards areas of lower sound velocity. At a certain depth, water becomes isothermal, ie, uniform in temperature, so temperature no longer impacts sound velocity. Rather, it is pressure.
The pressure increase is uniform, resulting in approx. 1.7 ft/sec increase in sound velocity per 100 ft. of depth.
This has the effect, in deep water, of bending the sound rays back towards the surface (where the sound velocity is lower), where they are again reflected downwards. It is at this point on the surface where the sound waves converge that is the CZ.

I don't understand Figure 6. My understanding is that colder water is more dense, therefore the speed of sound should be faster in colder (deeper) water. However, Figure 6 seems to indicate the opposite. What am I missing here?

This is great thanks but please apply this to the game where the statement "CZ at 12 - 24 - 36 - 48" is made.What is this telling me as a player of this game?

It means you can detect, and be detected by, ships or subs, via sonar, in narrow zones at the ranges specified... ranges which would otherwise be way beyond normal sonar detection range.

JD

The diagram below might help. The point where the sound rays converge is a CZ. A source of sound (emitter) in that zone can be detected, but if it is outside of that zone, the
emmitter is not detectable via CZ propagation. Effectively, a CZ gives you greatly enhanced detection ranges. Typically, the first CZ is in the neighborhood of 25-30 miles from the emitter, the second is double that, and the third is triple that. They are also fairly narrow, only a few nautical miles in width.
In your example, there would the first CZ would be at 12nm, the second at 24nm, the third at 36, etc.

This is great thanks but please apply this to the game where the statement "CZ at 12 - 24 - 36 - 48" is made.What is this telling me as a player of this game?

Just want to says thanks for that. Forgive me I was a Finance Major.[:)]