postion of a verb in the sentence

Yes, it is grammatically correct

In addition, the increase of entropy generation around the CTB and along the CTB length at Fi=0.275 means that there is a stronger turbulent interaction between the TLV and the mainstream around the CTB’s suction surface than the VTB’s suction surface.

The noun is "the increase"

There is a compound prepositional phrase "of entropy generation around the CTB" and "along the CTB length at Fi=0.275"

The verb is "means"

There's also another prepositional phrase "between the TLV and the mainstream around the CTB’s suction surface"

To verify this, let's cut out the prepositional phrases.

In addition, the increase means that there is a stronger turbulent interaction than the VTB's suction surface.

I'm not sure if the comparison is appropriate, but one can always cut the prepositional phrases to verify if a sentence's structure is sound. If it isn't sound without the prepositional phrases, adding in prepositional phrases won't fix the sentence structure.

I believe the use of means is grammatically correct here.

Your sentence can basically be broken down into The increase in X means Y, which is correct, so despite X and Y both being pretty long phrases, the sentence remains grammatically correct.

That said, the sentence is a bit of a mouthful. One way it can be simplified is by replacing the phrase "means that there is" with "indicates."

In addition, the increase of entropy generation around the CTB and along the CTB length at Fi=0.275 indicates a stronger turbulent interaction between the TLV and the mainstream around the CTB’s suction surface than the VTB’s suction surface.

The other opportunity for clarification in this sentence is with the phrase "...than VTB's suction surface." I had to read this sentence several times because that part confused me.

You seem to set up a contrast between two interactions, so I was expecting a set up of stronger...between X and Y than [between] A and B. But to me, if

• X = the TLV
• Y = the mainstream around the CTB's suction surface
• A = the VTB's suction surface

then you end up with a construction that sounds like stronger...between X and Y than [between] A – but where's B?

But eventually it occurred to me that maybe you're contrasting the interactions around the two suction surfaces. If that's indeed the case, inserting "around" before "the VTB's suction surface" would help tremendously in clearing things up:

In addition, the increase of entropy generation around the CTB and along the CTB length at Fi=0.275 indicates a stronger turbulent interaction between the TLV and the mainstream around the CTB’s suction surface than around the VTB’s suction surface.

With that addition, your sentence is basically shorthand for "...indicates a stronger turbulent interaction between the TLV and the mainstream around the CTB's suction surface than between the TLV and the mainstream around the VTB's suction surface."