being broody is a physical condition, not a mental one, she can not make up her mind to be broody, and there is little you can do to stop her. Most hens that go broody will sit even if you take her eggs away completely. My suggestion, is get some fertile eggs and enjoy the experience! a big hen like that will keep her babies safe in the average hen house, or you can seperate her in the final few days to keep her stress levels down.
The other option is give her some golf balls to sit on. If you keep taking her eggs, she may start hiding them from you, and that opens a whole new can of worms! She doesnt know or care if they are fertile or not, or connect the fact that you dont have a rooster to whether her eggs will hatch, she is just doing what physiology tells her to do....
Moving her, dumping water on her, or any of the other odd ideas I have seen are not effective and just lead to a grumpy wet hen and nest box. The hen will not starve herself to death sitting on the eggs, but she will get thinner, she will get up once a day to eat and drink. Usually after they go broody, they molt, so it will be a while until you get eggs from her again, but dont worry, she will fire up again and give you a whole 'nother round.
You cant fight mother nature, but some times you can fool her.
Be patient, and Good Luck.