Gear Flowmeter Dynamic Flow Measurement Research

Flow rate signal must be measured and controlled by technicians and researchers as one of the monitor parameters in the modern hydraulic equipment and hydraulic test system.Positive displacement flowmeters are widely used because of many advantages like high measuring accuracy and strong adaptability to the working environment among the many kinds of the flowmeters. However, if the positive displacement flowmeters be set up in the hydraulic system, flow and pressure ripple will be generated after the fluid get through the meter, which is extremely detrimental to the stable operation of the system. There are also many problems in the flow coupling of the hydraulic system. So it is important to research on dynamic flow coupling and reduce the flow pulsation.A new planet-gear flowmeter structure based on the structure of the traditional gear flowmeters has been presented in this paper. The structure and characteristics of the planet-gear flowmeter is introduced in this paper. Compared with the traditional gear flowmeters, the pulsation is smaller, it is more beneficial for stable operation and flow measurement system, In the meantime, there are many calculation methods of parameters especially the modification coefficient of internal meshing and external meshing are presented, in order to rationalize the structure and reduce the flow pulsation.With the use of the hydraulic simulation software, a system model has been built to study the coupling relationship. We did a series research on coupling frequency and coupling frequency, which illustrate the following feature and the static feature of the coupling frequency as well as the influencing factors and correlativity on flow coupling amplitudeThen a test bench of flowmeter dynamic performance and calibration has been designed, design parameters of each part are summarized. The design of hydraulic integrated valve block has been mainly introduced and it’s engineering drawing was given in this paper. Based on this, the test bench is manufactured with the function of testing the dynamic performance of flowmeter and calibration, which is prepared for the related experiment. Finally three kinds of flowmeter calibration method has been introduced, each method and parameter calculation has been explained. The calibration and pressure experiment of flowmeter have been done on the test bench, which obtained the measurement precision of flowmeter and illustrates the pressure resistance of flowmeter.