Conferences Attended

15th International Conference on Thermal Engineering: Theory and Applications (ICTEA-2024)

May, 29 - June, 1, 2024 , TASHKENT, Uzbekistan

Vol. 1 No. 1 (2024): ICTEA 2024 

Link: Article Access Link 

Liquid Jet in Cross Flow Modeling Under Different Weber Numbers 

Abstract:

Many applications employ liquid jet in cross flow (LJICF) configuration such as fuel spray in gas turbine combustion chambers, sanitizer spray subjected to airflow, agricultural sprays under wind conditions, etc. The Weber numbers (We) vary widely, and the model prediction across the range needs to be assessed. The present work investigates the modelling prediction for LJICF configurations by comparison with the available experimental data. Turbulence is modelled using the Reynolds Averaged Navier-Stokes (RANS) approach, and the discrete phase modelling is accomplished via the Eulerian-Lagrangian approach using a finite volume method-based solver. The primary breakup model used is cone injection, and the Madabhushi model is used for secondary breakup. The results for droplet size show good agreement at higher Weber numbers, while the model underpredicts the droplet sizes for low Weber number cases.

9th Thermal and Fluids Engineering Conference (TFEC)

April, 21-24, 2024, Corvallis, OR, USA 

DOI: 10.1615/TFEC2024.irn.051246 

NUMERICAL INVESTIGATION OF DROPLET DEFORMATION UNDER PULSATING FLOW

Abstract:

The droplet motion, deformation and breakup is widely investigated as it is prevalent in many applications such as IC engines, gas turbines, rocket engines, medical devices and airborne disease transmission. A comprehensive body of experimental and numerical studies exists for droplet subjected to continuous gas streams. However, in certain situations like thermoacoustic instabilities in rocket engines and gas turbines, the droplet is subjected to a pulsatile flow, and droplet behavior under these conditions is investigated in this work. Numerical simulations are performed using the finite volume technique, applying the Volume of Fluid (VOF) method to track the droplet-gas interface effectively. The adaptive mesh refinement technique effectively reduces cell count and, hence, the computational cost. The 3-D simulations for steady flow are validated with the experimental data. Next, the pulsatile flow is simulated using a time-dependent sinusoidal gas velocity and the effects of amplitude and frequency on breakup time and droplet evolution are studied. The 3-D pulsatile simulation compares well with the 2-D pulsatile simulation, which is computationally much less expensive and hence used extensively for parametric studies. The breakup time is compared with that of uniform flow conditions. The pulsation of the crossflow stream was found to accelerate the breakup process. The pulsation amplitude is found to affect more than the frequency of flow.

7th Thermal and Fluids Engineering Conference (TFEC)

May, 15-18, 2022 , Las Vegas, NV, USA

DOI: 10.1615/TFEC2022.fnd.040904 

NUMERICAL INVESTIGATION OF INCLINED LIQUID JET UNDER CROSS FLOW

Abstract:

Liquid jet in cross flow (LJICF) occurs in many applications such as sanitizer spray subject to surface wind, agricultural sprays, fuel spray in gas turbine combustion chambers, etc. In agricultural sprays subjected to cross flow, smaller droplets are often deposited off-target, which is known as spray drift. This is undesirable as the pesticide does not get applied to the target crop and causes harm at the non-target site. The liquid breakup length and the droplet size affect the droplet trajectory. It is reported that droplet size also depends on the injection angle with respect to the cross flow air. Therefore, drift can be controlled in a cross flow by adjusting the angle of injection relative to cross flow. Agricultural sprays are generally characterized by low Weber number and limited literature is available on low Weber number sprays. In the present work, the effect of injection angle on diameter distribution of the droplets and their trajectory for a low Weber number spray is investigated using computational fluid dynamics (CFD). Turbulence is modeled using Reynolds Averaged Navier-Stokes (RANS) approach and the discrete phase is modeled Euler-Lagrange approach, using ANSYS FLUENT. The effect of different primary breakup models (single point injection, plain orifice model) as well as secondary breakup models (TAB and KHRT) is studied. The Sauter Mean Diameter (SMD) and droplet velocity are investigated for different injection angles. The results show qualitative agreement with the experimental data available.