Fluid-Structure Interaction in the Nozzle of Collunarium Container

Author(s):  
Daisuke Yamaguchi ◽  
Kazuaki Inaba

Nasal administration of the vaccine is in the spotlight and the medicine has been developed in recent years. The medication is carried out by spraying the medicine in the nasal cavity by collunarium container. The top nozzle part of a common collunarium container consists of three parts, nozzle tip having an exit, cylindrical nozzle, and stepped center rod which is inserted into the nozzle. We confirmed that the spray of collunarium container consists of two stages phenomena (initial jet and its disintegration, and steady spray stage) by visualization with high-speed video camera. Since we found that the initial jet impacted with larger droplet size than later sprayed droplet, we examined the initial jet and steady spray stage in experiments and numerical simulations to study the effect of material and dimension of the rod. The dimensions of the center rod affected the acceleration of the initial jet front and the spray angle in experiments. In numerical simulations including fluid-structure interaction (FSI), lower density rod moved at faster speed and excited higher flow velocity at the exit in the jet stage. Moreover we confirmed that the acceleration of the jet was initiated by the water hammer wave propagation inside the nozzle.

Author(s):  
Riccardo Traversari ◽  
Alessandro Rossi ◽  
Marco Faretra

Pressure losses at the cylinder valves of reciprocating compressors are generally calculated by the classical equation of the flow through an orifice, with flow coefficient determined in steady conditions. Rotational speed has increased in the last decade to reduce compressor physical dimensions, weight and cost. Cylinder valves and associated gas passages became then more and more critical, as they determine specific consumption and throughput. An advanced approach, based on the new Fluid Structure Interaction (FSI) software, which allows to deal simultaneously with thermodynamic, motion and deformation phenomena, was utilized to simulate the complex situation that occurs in a reciprocating compressor cylinder during the motion of the piston. In particular, the pressure loss through valves, ducts and manifolds was investigated. A 3D CFD Model, simulating a cylinder with suction and discharge valves, was developed and experimentally validated. The analysis was performed in transient and turbulent condition, with compressible fluid, utilizing a deformable mesh. The 3D domain simulating the compression chamber was considered variable with the law of motion of the piston and the valve rings mobile according to the fluid dynamic forces acting on them. This procedure is particularly useful for an accurate valve loss evaluation in case of high speed compressors and heavy gases. Also very high pressure cylinders, including LDPE applications, where the ducts are very small and MW close to the water one, can benefit from the new method.


2018 ◽  
Vol 203 ◽  
pp. 06016 ◽  
Author(s):  
Ameen Topa ◽  
Do Kyun Kim ◽  
Youngtae Kim

Seamless pipes are produced using piercing rolling process in which round bars are fed between two rolls and pierced by stationary plug. During this process, the material undergoes severe deformation which renders it impractical to perform the numerical simulations with conventional finite element methods. In this paper, three dimensional numerical simulations of the piercing process are performed with Fluid-Structure Interaction (FSI) Method using Arbitrary Lagrangian-Eulerian (ALE) Formulation with LS DYNA software. The results of numerical simulations agree with experimental data of Plasticine workpiece and the validity of the analysis method is confirmed.


2015 ◽  
Vol 76 (9) ◽  
Author(s):  
Zulkifli Abdul Ghaffar ◽  
Salmiah Kasolang ◽  
Ahmad Hussein Abdul Hamid ◽  
Ow Chee Sheng ◽  
Mimi Azlina Abu Bakar

A wider spray angle produced by an atomizer is often required in providing a better spray dispersion. The formation and wideness of the spray angle were reported to be affected by the changes in geometrical parameters. In the present study, the effect of the interaction between two geometrical parameters (swirl-generating vane angle and discharge orifice diameter) on the swirl effervescent atomizer spray angle was studied. A newly-designed swirl effervescent atomizer was developed with 30°, 45° and 60° swirl-generating vane angle and 1.5, 2.0 and 2.5mm discharge orifice diameter. The atomizer performance tests were carried out using water as the working fluid and nitrogen gas as the atomizing agent. High-speed shadowgraph technique was deployed to record the resultant sprays produced. Video recordings, acquired using a high-speed video camera, were converted to a sequence of images for further analysis using image processing software. It was found that geometrical parameters of the newly designed atomizer have a great impact on the formation and characteristics of the spray angle. The combined effect of both swirl-generating vane angle and discharge orifice diameter has produced an increase in the spray angle. The largest spray angle was observed at the largest dimension of both geometries.


Author(s):  
Mohammad A. Elyyan ◽  
Yeong-Yan Perng ◽  
Mai Doan

Flow-induced vibration (FIV) is one of the main reasons for subsea piping failure, where subsea pipes, which typically carry multiphase flow, experience large fluctuating forces. These fluctuating forces can induce severe vibrations leading to premature piping failure. This paper presents a transient numerical study of a typical subsea M-shape jumper pipe that is carrying a gas-liquid multiphase flow subject to a slug frequency of 4.4 Hz, starting from rest to include the start-up effect as part of the study. 3-D numerical simulations were used to capture the fluid-structure interaction (FSI) and estimate pipe deformations due to fluctuating hydrodynamic forces. In this paper, two FSI approaches were used to compute the pipe deformations, two-way coupled and one-way decoupled. Analysis of the results showed that decoupled (one-way) FSI approach overestimated the peak pipe deformation by about 100%, and showed faster decay of fluctuations than coupled (two-way) FSI analysis. The assessment of resonant risk due to FIV is also discussed.


2008 ◽  
Vol 9 (1) ◽  
pp. 137-146 ◽  
Author(s):  
Jin-Ho Kim ◽  
Jae-Woo Lee ◽  
Soo-Hyung Park ◽  
Do-Young Byun ◽  
Yung-Hwan Byun ◽  
...  

2015 ◽  
Vol 39 (4) ◽  
pp. 749-766
Author(s):  
Matthew G. Doyle ◽  
Stavros Tavoularis ◽  
Yves Bougault

Numerical simulations of blood flow and myocardium motion for an average canine left ventricle (LV) with fluid-structure interaction were performed. The temporal variations of the LV cavity pressure and wall stress during the cardiac cycle were consistent with previous literature. LV cavity volume was conserved from one period to the next, despite sub-physiological ejection volumes and brief periods of backflow during early filling. This study improves on previous ones by presenting details of the models and results for both the fluid and solid components of the LV.


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