The symbol Valknut is one of the symbols of Scandinavian paganism, which is associated with the name of the god Odin. One was considered the patron of the fallen soldiers, and the word Valknut just means "knot of the dead." Another thing is that this name was invented by modern researchers for the ancient rune, and as it was called before, it is not known.
The value of the symbol Valknut
The combination of the three triangles in this symbol is treated as a junction of three of the nine worlds: Hel, Midgard and Asgard (with Valhalla, the place where the warriors rest). One has the name of the Great Wanderer, which, it seems, also brings him closer to the "heart of Hrungnir". However, the image of Valknut does not occur either with Odin or with his symbols. Perhaps, the interpretation of the symbol is erroneous, and it is connected, say, with Heimdall.
It is very likely that the symbol Valknut is connected not so much with the local worlds as with the other-worldly.
There are other interpretations, including even the "human" triad: body-soul-spirit. Which, naturally, can in no way be related to Old Norse mythology and is a later interpretation, presumably under the influence of Christianity.
Tattoos Waltz
The generally accepted opinion at this time about this symbol is that it connects the nine worlds (9 is the sacred number of the ancient Scandinavians). Thus, the Tattoo Valknut must mean the ability to know all nine worlds or a connection with them all. Tattoos in ancient times were made with the purpose of protection from evil spirits: so to speak, the guardian, which is always with you. They worked on symbols, the meaning of which was to call good forces and defense against evil ones. Could the ancient Scandinavians have used Valknut in this sense? Hardly. There is no reason to believe that they were wearing tattoos. Is there any reason to believe that nowadays Valknut has acquired the power of an amulet ? Even if we assume that this is in principle possible, then it is unclear why such a force should be attributed to the "heart of Hrungnir" - is he, a good spirit, or what? So Valknut and its importance as a tattoo is not at all a simple question. Is it worth it for occult reasons? What if it's an unkind sign?