Yes. The most effective technique (from qigong, which is Chinese yoga) to prevent heartburn is simply to chew your food slowly. (I know a man who spent thousands of dollars getting advice from doctors that didn't help his heartburn, then learned this one simple technique from my health coach, a qigong teacher, in five minutes. Boy was he mad!)
For actual yoga positions (asanas), the child pose, done very gently, is probably best. Standing postures, such as the Warrior pose variations, that expand the abdominal area and chest, freeing the diaphragm, would also be good.