Study Of Dometic Low Power Consumption Ultrasonic Heat Meter

There are various heat meter products in home market today. Most of them use impeller flow sensor as flow measurement unit, which need good water supply qulity and the material and structure of impeller can be influenced by temperature to a great extent. Considering these shortcomings, a dometic ultrasonic heat meter based on ultrasonic flow measurement function is designed. Looking at the tendency of international heat meter development, the demand for ultrasonic heat meter is increasing rapidly.A thermal measurement model based on enthalpy difference is deduced and the hot water density and enthalpy formulas are compensated and predigested. For mechanical structure of ultrasonic heat meter, ultrasonic transducers are installed with fixed short pipe V mode. A new insert type ultrasonic transducer is designed, which conveniences to exchang transducer and no draining is necessary.Some theory studies are done for enhancing ultrasonic flow measurement accuracy. Using a method of sound pulse circle to measure ultrasonic wave transmit-time in home heat-supply pipelines, which is a good solution for small diameter pipe and low flow velocity application. Furthermore, two temperature signals are amplified via the same amplification circuit that ensure to measure difference in temperature exactly. Microprocessor MSP430F448 is the core of ultrasonic heat meter. The hardware and software design of this intelligent instrument system are accomplished and accordingly the information of flow, thermal and time can be displayed with key-press. The whole system accords with low power consumption principle. All electronic components are low voltage...