Development Of Totalizer In Gas Ultrasonic Flowmeter

Ultrasonic Gas Flowmeter is a kind of non contact type instrument, which is developed with the rapid growth in integrated circuit technique field in recent years, suitable for difficult situation to contact and observe fluid and large pipe. It own huge advantages, such as could detect bi-direction fluid, super large range, zero pressure loss, high measuring accuracy, no mechanical errors and so on, so it is widely used in oil, chemical, metallurgy, electricity, plumbing code fields. Totalizer is part of ultrasonic gas flowmeter, although the similar products were existed in market for several years, but they are designed to other kinds of flowmeters, such as turbine meter, vortex flowmeter, and rotameter and so on, so it is not common to find totalizer designed to ultrasonic gas flowmeter. This project is designed to design a totalizer product, which is suitable for ultrasonic gas flowmeter, own the functions to change natural gas working volume into standard volume and accumulate the volume data, at the same time, has the function to send signal to other equipments. This paper is explained by five chapters.In the first chapter, give a brief introduce to development history about flow measurement technique, ultrasonic flowmeter and rotameter, then introduce present research situation of home and abroad about totalizer and ultrasonic flowmeter. At last, based on the requirements, come up with the project research purpose;In the second chapter, based on engineering requirements, designed RS485 communication interface for ultrasonic gas flowmeter, make it possible to exchange flow data, temperature data, pressure data in the working system, reflect instrument working status;In the third chapter, based on the functions requirements, designed the whole system, including hardware and software. Own the functions to set parameter through key cooperate combination, build natural gas compressibility factor computational model in microprocessor, and send pulse under super large turndown ratio to verify flowmeter performance;In the last chapter, test designed prototype functions performance, including cumulative calculation to transient flow, gas volume conversion accuracy, and pulse send accuracy and whole ultrasonic gas flowmeter working performance with totalizer.Then I make a summary to the research work, combined with the technical development, come up with some expectations in the future.