After a human dies, what happens to their blood? I know that it tends to accumulate in the lower areas of the body, whichever parts are closest to the ground, but I am wondering about coagulation. Does the blood always coagulate? How long does this take? Does it ever "de-coagulate"? If so, how long does that take? If it coagulates, then "de-coagulates", does it "re-coagulate"? How long does that take?
Note: I'm asking this question because I am a fan of The Walking Dead, but I have always been a bit puzzled by the fact that on that show, the blood of zombies (who are dead) is consistently depicted as being fluid, dark red, and not coagulated at all. I'm obviously not asking about the particulars of zombie blood, because zombies don't exist (yet). I'm just curious as to whether it is possible for blood to remain liquid, and similar in appearance to the blood of living people, after death has occurred. You can see my related question, on SF&F.SE, by clicking here.