Hopefully, he will come around sooner or later.]/quote]
You say you were at budget on one and close to budget on another. Budget over-runs are not unusual and thus one has to question if perhaps the problem is that before the projects completed he had been making claims to senior management that these would be brought in "well under-budget". Also not to be over-looked is that he made his comments, not in private to you but in a meeting where he has done the maximum damage to you.
This is not, in my opinion, professional. Indeed, it smels to me like "scape-goating". He isn't going to come round.
The question is, what is your work environment like now? How much is this affecting you?
How is it likely to affect your career prospects?
At some point you may need to approach HR to get the work situation resolved. You may need to take some legal advice.
I suggest that you take some time and write up a detailed account of the incident at the meeting and of the two projects. You may also try and get some comment from others.
What you have to face is the prospect that the work environment may bring with it some health issues as you are now under sustained stress and you also have to be careful about how the worry affects home life. Also, you need to ask what is this doing to your career prospects both within this company and when you try to move on.
Then too, you only know what he has said to you in the meeting, you do not know what he has said to the management nor what is now in your personnel file.
Don't take this too lightly, don't simply assume that it is a case of working extra hard to prove yourself, it may be that this is a wasted effort if he is being unfair. If you think he was unfair then it isn't your engineering and being a better engineer isn't going to help.
Sanity check: talk with your co-workers in a relaxed off-site environment, talk to them individually and see from the first discussion if you can establish what is gong on.
Some times "bullies" get away with it because they can. They may often pick on new employees because they are less sure of themselves and don't know what to expect.
However, if you discover the criticisms valid, if your co-workers will tell you you messed up, then learn from it. Still, if that is the case then it is for your "mentor" to help you bring your standards up to expectation. Ultimately that is for the head engineer, it is his team and he is answerable for its quality and performance.
It may be that there have been a succession of people who have joined, been scape-goated and left with a stain on their reputation. If so, and if it gets nasty, you might need to talk with some of them. You were employed as a replacement? or as part of expansion? i.e. did you replace someone and why did they go (always a question during interviews).
In any event, get that CV out there and look for a new job. You may need a refuge...
JMW