Welcome to HCM.
Ovulation means release of ovum from a follicle after it has matured and ruptured, which usually occurs approx. on the 14th day of menstrual cycle.
Fallopian tubes are the extensions of the uterus
which transport the ovum nearer to the uterine cavity
. Fertilization occurs in the tube and the fertilized egg is transported into the uterine cavity where it gets embedded and the baby grows over there.
I think that now it must be clear to you that ovulation and tubes are different things. Ovulation can occur even if the tubes are blocked but the transportation will not be successful if the tubes are blocked. If both the tubes are completely blocked then ovum and sperm cannot unite and hence pregnancy
is not possible in natural way. Artificial techniques will be necessary in such cases.
Wish you all the best.