Influence of Nozzle Divergent Part Length and Throat Diameter on Vortex Control of Initially Subcooled Flashing Flow

2017 ◽  
Vol 10 (1) ◽  
pp. 121-127 ◽  
Author(s):  
Jingwei Zhu ◽  
Stefan Elbel
Designs ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 4
Author(s):  
Dillon Alexander Wilson ◽  
Kul Pun ◽  
Poo Balan Ganesan ◽  
Faik Hamad

Microbubble generators are of considerable importance to a range of scientific fields from use in aquaculture and engineering to medical applications. This is due to the fact the amount of sea life in the water is proportional to the amount of oxygen in it. In this paper, experimental measurements and computational Fluid Dynamics (CFD) simulation are performed for three water flow rates and three with three different air flow rates. The experimental data presented in the paper are used to validate the CFD model. Then, the CFD model is used to study the effect of diverging angle and throat length/throat diameter ratio on the size of the microbubble produced by the Venturi-type microbubble generator. The experimental results showed that increasing water flow rate and reducing the air flow rate produces smaller microbubbles. The prediction from the CFD results indicated that throat length/throat diameter ratio and diffuser divergent angle have a small effect on bubble diameter distribution and average bubble diameter for the range of the throat water velocities used in this study.


2021 ◽  
Vol 33 (1) ◽  
pp. 74-85
Author(s):  
Yi-qian Wang ◽  
Hai-dong Yu ◽  
Wei-wen Zhao ◽  
De-cheng Wan
Keyword(s):  

2015 ◽  
Vol 667 ◽  
pp. 449-454
Author(s):  
Yang Hong ◽  
Xiang Zhang ◽  
Dong Xiang Shao ◽  
Guang Lin Wang ◽  
Li Sun

This paper proposes a hydraulic measurement model for measuring the Laval nozzle throat diameter size. Based on measurement principle of liquid pressure – flowrate, we can get the size of Laval nozzle throat diameter by measuring the fluid flowrate through hydraulic measurement model at the fixed pressure. With good viscosity-temperature performance, low temperature performance and oxidation stability, UCBO aviation hydraulic oil is selected as the measuring medium. In the hydraulic measurement model, the diameter of the mandrel which can be regarded as gauge will directly affect the sensitivity of diameter measurement. Therefore we need to optimize the design of the mandrel of the hydraulic model.


2006 ◽  
Vol 110 (1112) ◽  
pp. 673-681 ◽  
Author(s):  
P. Margaris ◽  
I. Gursul

AbstractAn experimental investigation was conducted to study the effect of synthetic jet (oscillatory, zero net mass flow jet) blowing near the wing tip, as a means of diffusing the trailing vortex. Velocity measurements were taken, using a Particle Image Velocimetry system, around the tip and in the near wake of a rectangular wing, which was equipped with several blowing slots. The effect of the synthetic jet was compared to that of a continuous jet blowing from the same configurations. The results show that the use of synthetic jet blowing is generally beneficial in diffusing the trailing vortex and comparable to the use of continuous jet. The effect was more pronounced for the highest blowing coefficient used. The driving frequency of the jet did not generally prove to be a significant parameter. Finally, the instantaneous and the phase-locked velocity measurements helped explain the different mechanisms employed by the continuous and synthetic jets in diffusing the trailing vortex.


1989 ◽  
Author(s):  
Dhanvada M. Rao ◽  
C. K. Puram ◽  
Gautam H. Shah
Keyword(s):  

1995 ◽  
Vol 32 (4) ◽  
pp. 739-745 ◽  
Author(s):  
D. Gangulee ◽  
T. Terry Ng

Author(s):  
K. Sakaki ◽  
Y. Shimizu ◽  
Y. Gouda ◽  
A. Devasenapathi

Abstract Effect of nozzle geometry (such as throat diameter of a barrel nozzle, exit diameter and exit divergence angle of a divergent nozzle) on HVOF thermal spraying process (thermodynamical behavior of combustion gas and spray particles) was investigated by numerical simulation and experiments with Jet KoteTM II system. The process changes inside the nozzle as obtained by numerical simulation studies were related to the coating properties. A NiCrAIY alloy powder was used for the experimental studies. While the throat diameter of the barrel nozzle was found to have only a slight effect on the microstructure, hardness, oxygen content and deposition efficiency of the coatings, the change in divergent section length (rather than exit diameter and exit divergence angle) had a significant effect. With increase in divergent section length of the nozzle, the amount of oxide content of the NiCrAIY coatings decreased and the deposition efficiency increased significantly. Also, with increase in the exit diameter of the divergent nozzle, the gas temperature and the degree of melting of the particle decreased. On the other hand the calculated particle velocity showed a slight increase while the gas velocity increased significantly.


Author(s):  
M. T. Landahl ◽  
S. E. Widnall
Keyword(s):  

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