I was going to ask the same re juice/broth vs. nutritional shakes. While you may still have some hunger with the nutritional shakes, they are designed to provide you with all the necessary nutrition, assuming you are taking in the correct amount of calories.
When my son did EN (enteral nutrition - formula/liquid only), he was taking in 3000 cal/day. As he ingested his formula overnight (through ng tube), he did have some hunger towards dinner time.
In addition to the formula, he was allowed clear fluids - pop, clear apple juice (ie no fibre), gatorade, popsicles, freezies, jello, broth, gummy candies, clear hard candies (ie lifesavers), gum, etc. To try to maintain a quasi diet, he took broth to school for lunch and we arranged with his school to keep a supply of freezies for him. In the evening, it was the same - broth and a freezie. We mixed up the broth - chicken, beef, veg, fish. I also changed the flavour of the broth slightly with spices (ie heat up the beef broth with some rosemary, and then strain!). I also varied the broth between bowl with spoon and a mug (just added a bit of 'mental' variety

).
You do need to be careful of the sugar - ie eating a box of freezies and a few bags of gummy candies wouldn't be a good idea!

But, I know that most people get sick of the 'sweet' anyway and the broth can help offset this.
But, a liquid diet should always be done under the supervision of your GI and, usually, a nutritionist.
A proper liquid diet can provide all the necessary nutrition while providing bowel rest. It is usually done for a period of 6-8 weeks. I'm not sure of the stats with adults but, with kids, it can be as successful as steroids at inducing remission. Success rates are highest when used for the first time.
While it hasn't been necessary, I have also sent my son enough formula to last him a few days when he travels. If he's not feeling well, it would give him an alternative until he can return home. As I said, it would provide him with nutrition while being easily absorbed (less work for the bowels). BUT, we would immediately see his GI and work with him before continuing indefinitely.