The Design And Experimental Research Of The Double-cone Flowmeter

Double-cone flowmeter is a new kind of differential pressure flowmeter. Because of its unique throttle structure, the double-cone flowmeter compared with other conventional differential pressure flowmeters has many outstanding advantages. Such as strong anti-disturbance ability, short straight pipe requirements, small pressure loss, etc. But the double-cone flowmeter has not yet been made into a mature integrated flow measurement instruments, and has not been widely applied to the field of flow measurement. So, first, the Computational Fluid Dynamics(CFD) software Fluent was used to make a simulation inquiry of the optimization of throttle structure. The next, some experiments were conducted for the investigation of double-cone flowmeter in this paper. And then designed a double-cone flowmeter which used the MSP430 microcontroller and could be directly used for pipe flow measurement. The real flow calibration was conducted and the accuracy was determined..The main work was as follows:1) Using the Computational Fluid Dynamics(CFD) software Fluent to make a 3D simulation inquiry of the further optimizing of throttle structure of double-cone flowmeter with 50 mm caliber and equivalent diameter ratioβ=0.586. By changing the angles of the cone angle of the front and rear to compare the flow field around the cone angle, pressure loss, flow coefficient and flow coefficient linearity between different combinations to find out the optimal combination.2) According to the simulation results, different equivalent diameter ratios of the double-cone flowmeters were designed and made. The experiments were conducted for the investigation of the pressure loss of double-cone flowmeters with 50 mm caliber and four equivalent diameter ratio β=0.424、0.586 、 0.697 、 0.78. The pressure loss and relative pressure loss of the standard orifice, nozzle flowmeters and V-cone flowmeter were compared in the condition of the same test medium, diameter ratio and caliber.3) Using an OEM differential pressure sensor and a core of MSP430F4794 microcontroller, this paper conducted a hardware design and software design of double-cone flowmeter. The double-cone flowmeter achieved real-time flow rate, total flow, temperature sensing, communications, human-computer interaction and other functions.4) The real flow calibration of double-cone flowmeter whose equivalent diameter ratio was 0.586 was conducted and the accuracy was determined.The uncertainty evaluation was completed at the same time.