从课本上学习对流不如自己亲自观察一下。纯粹由输运媒质本身显露出对流现象来时常是不容易的。这里介绍一个演示实验,可以使对流现象很易于观察到。在一支试管内装上水,水温为室温或稍低于室温。再加入一小撮铝粉,塞住试管口并摇动试管,保证使铝粒均匀分布在水中。然后,用手握住试管的底部,在数 Learning about convection from textbooks is not as good as looking at yourself. It is not always easy to reveal convection simply by the transport medium itself. Here is a demonstration experiment that makes it easy to observe convection. Fill the water in a test tube at room temperature or slightly below room temperature. Then add a small amount of aluminum powder, plug the test tube mouth and shake the test tube to ensure that the aluminum particles are evenly distributed in the water. Then, hold the bottom of the test tube with your hands.