How is the interview at IIT Bhubaneswar for an M.Tech thermal?What are the chances that a general category guy with 3061 rank and 704 score get a seat?

Chances are not much good as the number of seats in the thermal specialization are less (only 18) and IIT Bhubaneswar conducts a rigorous interview (half an hour to 45 minutes per candidate), within that duration you need to explain the topics on the board to the interviewers. Some of the interview questions asked in the previous year were boundary layer theory, transient heat conduction, the significance of Prandtl, Nusselt, etc.

The process for admission in the course is based on marks secured in graduation. The student must have 60% marks or 6.5 CGPA in a 10-point scale in Mechanical Engineering or equivalent (with a valid GATE score). 

The final selection of regular candidates will be based on the combined scores of the candidates in GATE (70%) and the written test (30%). The Written Test and Interview shall be given equal weightage of 15% each.

Students in the unreserved category will be eligible to sit in the interview subject to scoring a minimum of 40% marks in the written test and for final selection a minimum of 50% marks in the interview.

Hence, an interview becomes a very crucial factor in securing admission. It is completely technical in nature as explained above it judges the in-depth knowledge of the applicant in the subject. NPTEL lectures can be useful in preparing for the interview so as to enhance the understanding of the in-depth concepts of the subject in detail. Since the analysis part of some concepts as mentioned above can also be asked. The project report is also required there so one can expect questions from there also.

Finally, the cut off of the course is around 600 hence you can expect to have a fair chance if you have good understanding and command over your subjects.