Its a variation of a reflux still made popular by John Stone & Mike Nixon (which I called the "Nixon-Stone", but generically you could also call it a fractionating column or a compound still too.
V1 could be the "return line" or "drain" ?
You may not even need the valve on V1 - if you were to mount it slightly higher than V2, you could use it as simply an open line, that when V2 were partially or fully closed, the liquid would accumulate up to its height and automatically drain back into the column. This would be a little bit safer than running the risk of say having both V1 & V2 closed at the same time, and then filling that container all the way up (until it drained back to the column over the top = safe). By having V2 higher than V1, it would mean that when you do have V2 fully open, all the liquid would preferentially drain out through it.