The fertilizer suction capability of a Venturi injector is dependent on the vacuum pressure in the throat portion. As the vacuum level drops below the saturation vapor pressure, the pressure decreases to a particular value corresponding to the maximum pressure difference (Δpmax) between inlet and outlet pressures, and critical cavitation is likely to occur, leading to an unstable suction flow rate and low fertilization uniformity. A new method of using strain gauges to detect cavitation in Venturi injectors was explored experimentally and verified numerically under various operating conditions. The standard deviation (SD) of the measured strain values and the simulated values of the vapor-phase volume fraction (Vf) were used to evaluate the influence of cavitation. The results showed that both the rate of increase of the average SD and the average growth rate (AGR) of the simulated cavitation length reach relatively large values at the maximum pressure difference (Δpmax), where the measured suction flow rate simultaneously reaches a maximum. In addition, SD and Vf shared similar variation trends at pressure differences larger than the corresponding Δpmax under various conditions. This new cavitation detection method has been proved to be feasible and reliable. It helps to determine accurately the value of Δpmax at different inlet pressures and to ensure that the Venturi injector runs in a safe operating-pressure range.
Detection of Cavitation in a Venturi Injector With a Combined Method of Strain Gauges and Numerical Simulation
Contributed by the Fluids Engineering Division of ASME for publication in the JOURNAL OF FLUIDS ENGINEERING. Manuscript received March 29, 2013; final manuscript received February 17, 2014; published online May 15, 2014. Assoc. Editor: Olivier Coutier-Delgosha.
- Views Icon Views
- Share Icon Share
- Cite Icon Cite
- Search Site
Xu, Y., Chen, Y., He, J., and Yan, H. (May 15, 2014). "Detection of Cavitation in a Venturi Injector With a Combined Method of Strain Gauges and Numerical Simulation." ASME. J. Fluids Eng. August 2014; 136(8): 081302. https://doi.org/10.1115/1.4026879
Download citation file:
- Ris (Zotero)
- Reference Manager