tried to render my explosion which consisted of smoke and fire by following this tutorial: https://www.youtube.com/watch?v=DCswSYaYpFw
But the smoke and fire didn't show up, whether in rendered viewport or in final render. Then I tried to adjust the sun lamp to light up the smoke.
But it didn't work either. There was no difference. It was only shown in only black background but no gray smoke or orange fire. What did I do wrong?