中文摘要：

通过实验与理论计算方法，对燃气热水器的流量特性进行研究，得到水流量随供水压力变化的计算公式，将水流量的理论计算值与实测值进行对比。在较高供水压力下，实测值与理论值存在较大差异。实际上存在极限流量，当实际流量达到极限流量时，水流量不随供水压力的增大而增大，而是趋于稳定。对出水温度控制特性进行研究，虽然通过燃气阀门和水量调节阀可以调节出水温度，但其调节能力有限。

英文摘要：

The flow characteristics of gas water heater are studied by experimental method and theoretical calculation method. The calculation formula on variation of water flow with water supply pressure is obtained, and the theoretical calculation value and the measured value are compared. There is a big difference between the measured value and theoretical calculation value under high water supply pressure. In fact, the limit flow exists, and the water flow does not increase with increasing of water supply pressure, and it trends to be stable when the actual flow reaches the limit flow. The control characteristics of outflow temperature are also studied. Although the outflow temperature can be regulated by gas valve and water flow regulating valve, but their abilities to regulate is limited.