bsu685,
Are you intending to keep this knife in your accommodation or carry it at university/out and about? If you intend to carry it about, except when camping/hunting etc you CANNOT carry a fixed blade regardless of length. University grounds and buildings are classed as a public place.
If you want to carry a knife in public (except for specific tasks like camping) you may ONLY carry a "folding pocket knife with a cutting edge no greater than 3" in length". You should also be aware that if a knife has a lock, it is de facto not classed as a "folding pocket knife" so in effect you may only carry a folding, non-locking pocket knife with a cutting edge no greater than 3" in length.
If you want it only for specific outdoor tasks like camping then you may carry any blade suitable for the task i.e. an 18 inch machete, a 4 inch bushcraft knife, an axe etc.
Apart from a few exceptions like balisongs you can keep and carry any knife at home or on private property. However, landlords (including universities) can restrict what you can keep in your accommodation.