If you have some prior knowledge of mechanical engineering(I am referring here prior knowledge as above than average) and you want to learn about industrial or real life problems then YES IIT Delhi mechanical department won’t disappoint you.
Some of the Prof. are so good in their area of interest and currently doing many useful projects for industries and research science.
Like for design Prof Anoop Chawla and Prof Sudipto are so good;
For thermodynamics Prof P.M.V SubbaRao and Suprit singh Bagha;
For Manufacturing Prof PVM Rao;
For Industrial planning Prof Nomesh Bolia and Kiran Seth;
But(Yes,there is always a but) if you are not much prior interested in mechanical and you think that opting IIT Delhi will helps you in learning and generating more interest then this might not be the truth as profs here are not good or even average as a teacher. Classes are so so boring and ultimately you will start bunking lectures.