Computational Fluid Dynamics Analysis for Process Impact Assessment during Thermal Pasteurization of Intact Eggs

2005 ◽  
Vol 68 (2) ◽  
pp. 366-374 ◽  
Author(s):  
SIEGFRIED DENYS ◽  
JAN G. PIETERS ◽  
KOEN DEWETTINCK
Keyword(s):  
Heat Transfer ◽  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Inactivation Kinetics ◽  
Transient Temperature ◽  
Process Conditions ◽  
Conductive Heat ◽  
Cfd Analysis ◽  
Computational Fluid Dynamics Analysis ◽  
Thermal Pasteurization

Transient temperature and albumen velocity profiles during thermal pasteurization of intact eggs were studied using a commercial computational fluid dynamics (CFD) package. Simulated temperature profiles were in close agreement with experimental data for eggs of different sizes. Convective heat transfer only occurred in the egg white fraction, and conductive heat transfer only occurred in the yolk. For process assessment, a generally accepted kinetic inactivation model for Salmonella Enteritidis was incorporated into the CFD analysis. Minimum process times and temperatures needed to provide equivalent pasteurization at 5-log reductions of the target microorganism were obtained on a theoretical basis. The combination of CFD analysis and inactivation kinetics can be very useful for assessing pasteurization of intact eggs and can enable processors to gain a better understanding of these processes and to establish process conditions for consumer-safe eggs.

Computational Fluid Dynamics Analysis of Aerodynamics and Impingement Heat Transfer From Hexagonal Arrays of Multiple Dual-Swirling Impinging Flame Jets

2020 ◽  
Vol 142 (8) ◽  
Author(s):  
Parampreet Singh ◽  
Ratna Kishore Velamati ◽  
Subhash Chander
Keyword(s):  
Heat Transfer ◽  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Target Surface ◽  
Separation Distance ◽  
Release Mechanism ◽  
Hexagonal Array ◽  
Array Configuration ◽  
Computational Fluid Dynamics Analysis ◽  
Impinging Flames

Abstract Radiative furnaces pose significant thermal inertia and single impinging flames have been observed to cause occurrence of hotspots on the target surface. Multiple burners arranged in suitable array configuration represent one of the plausible solutions for more uniform heat transfer. In this study, computational fluid dynamics (CFD) simulations have been carried out for multiple swirling impinging flames arranged in a hexagonal array configuration. The turbulence chemistry interactions in the flame field are solved numerically using renormalization group (RNG) based k–ε/eddy dissipation model (EDM) framework. Comparison of co-and-counter-swirling configurations has been studied for interactions and spent gas release mechanism. Multiple swirling impinging flames undergo strong interactions resulting in distortions of recirculation zones (RCZ) for all the surrounding except central flame. Co-swirling flames result in development of higher turbulence in the interaction regions as compared to counter-swirl case. Results indicate that some flames in counter-swirl case are underutilized due to the fluid dynamics developed in the system and co-swirling hexagonal array configuration is a better arrangement for effective heating of target surface. Effect of interjet spacing (S/Dh = 5, 7, and 9) and separation distance (H/Dh = 3, 5, 7, and 9) studied for co-swirl case revealed that peak heat fluxes decreased with increasing interjet spacing and separation distance. Central flame represented a region of low heat flux and this region has been noticed to expand in size for increasing interjet spacings. Suppression of central flame has been observed to be maximum for minimum separation distance.

scholarly journals Enhancement of Film Boiling Characteristics Using Computational Fluid Dynamics Analysis for Moving Steel Plate

2020 ◽  
Vol 6 (2) ◽  
pp. 33-42
Author(s):  
Ritu Raj ◽  
Vardan Singh Nayak
Keyword(s):  
Heat Transfer ◽  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Steel Plate ◽  
Saturation Temperature ◽  
Film Boiling ◽  
Dynamics Analysis ◽  
Fluid Temperature ◽  
Plate Surface ◽  
Computational Fluid Dynamics Analysis

Present study provides guidelines and recommendations for solving film boiling problems in steel plate production, where the surface temperature of steel plate is much higher than the saturation temperature of the liquid in contact with the plate surface and the entire steel plate surface is immersed in water. Due to the boiling mass exchange occurring at the vapor liquid interface bubbles of steam are periodically produced and emitted upward such a regime is known as film boiling. A computational fluid dynamics analysis of steel plate using VOF multiphase model moving at different velocity i.e. 0.1 to 0.5 m/sec. the volume of fraction for vapor phase have been obtained for different time interval, the generation of bubbles starts moving upwards after 0.05 sec, as time goes the formation of vapor bubbles generate and collapse more rapidly because the thermal boundary is very thin and the fluid temperature around the bubbles almost equal to the saturation temperature. The thermal properties of the steel plate are implicit to be constant with temperature for convenience because the present study is focused on the boiling heat transfer on the steel plate. The size of element is set as 0.1 mm to generate mesh and quad-4 rectangular elements used are which is a rectangular in shape with four nodes on each element are applied for the analysis. Results show that that the 37.98% of Convective heat transfer coefficient of mixture is increased and 13.1% of temperature drop has been observed with 40.67% of heat flux increased for the steel plate moving at 0.1 m/sec.

scholarly journals Aerodynamic Analysis of Spoiler at Varying Speeds and Angles

2021 ◽  
Vol 9 (11) ◽  
pp. 526-535
Author(s):  
Manas Metar
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Cfd Analysis ◽  
Wake Region ◽  
Aerodynamic Analysis ◽  
Pressure Drag ◽  
High Speeds ◽  
Computational Fluid Dynamics Analysis ◽  
Computational Fluid Dynamics Cfd ◽  
Simulation Results

Abstract: Spoilers have been there in practice since years for the purpose of improving aerodynamics of a car. The pressure drag created at the end of the vehicle, referred to as wake region affects handling of the vehicle. This could be hazardous for the cars at high speeds. By adding a spoiler to the rear of the car reduces that pressure drag and the enhanced downforce helps in better traction. The paper presents aerodynamic analysis of a spoiler through Computational Fluid Dynamics analysis. The spoiler is designed using Onshape software and analyzed through SIMSCALE software. The simulation is carried out by changing angles of attack and velocities. The simulation results of downforce and drag are compared on the basis of analytical method. Keywords: Designing a spoiler, Design and analysis of spoiler, Aerodynamics of spoiler, Aerodynamic analysis of spoiler, Computational fluid dynamics, CFD analysis, CFD analysis of spoiler, Spoiler at variable angles, Types of spoilers, Analytical aerodynamic analysis.

Evaluation of Jet Impact Region and Fluid Force Generated From Ruptured Pipes: 2 — Evaluation of Fluid Force Using Computational Fluid Dynamics Analysis

2016 ◽  
Author(s):  
Shiro Takahashi ◽  
Qiang Xu ◽  
Noriyuki Takamura ◽  
Ryo Morita ◽  
Yuta Uchiyama ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Nuclear Power ◽  
Power Plants ◽  
Jet Impingement ◽  
Cfd Analysis ◽  
Fluid Force ◽  
Free Jet ◽  
Jet Impact ◽  
Computational Fluid Dynamics Analysis

Nuclear power plants are designed to avoid damage to their safety installations because of jet impingement when a pipe is ruptured. We have investigated evaluation methods for the design basis of protection of plants against effects of postulated pipe rupture using computational fluid dynamics (CFD) analysis. The steam jet tests obtained using particle image velocimetry (PIV) were conducted in order to verify the CFD analysis. Spread of steam jets could be visualized and the shapes of the steam jets obtained by analysis were almost the same as those by tests. The spread angle of free jet was investigated using CFD analysis. We also measured jet fluid force when a cylindrical structure was installed downstream from the jet nozzle. Steam jet fluid force obtained by analysis was almost the same as that by tests. We judged the CFD analysis to be applicable to evaluation of jet fluid force generated from ruptured pipes.

Characteristic Study of Bi-Cone Solid-Liquid Separation Hydrocyclones Based on Computational Fluid Dynamics Analysis

2007 ◽  
Author(s):  
Lixin Zhao ◽  
Baojun Zhu ◽  
Yanqing Hu ◽  
Zhanzhao Ma
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Short Circuit ◽  
Tangential Velocity ◽  
Cfd Analysis ◽  
Liquid Separation ◽  
Distribution Rule ◽  
Computational Fluid Dynamics Analysis ◽  
Solid Liquid ◽  
Solid Liquid Separation

Numerical simulation of the bi-cone solid-liquid separation hydrocyclones based on Reynolds Stress Model (RSM) is carried out by Computational Fluid Dynamics (CFD) analysis. Re-circulation flow and short-circuit flow phenomena are indicated by simulating results, and distribution rule of axial velocity, radial velocity and tangential velocity of the flow field inside hydrocyclone are obtained. Some of the simulation results are qualitatively in accordance with the Laser Doppler Anemometer (LDA) measuring data, which proves the correctness of turbulence model and computational method. Moreover, the wall erosion problem of the hydrocyclones is also studied. The positions of erosion, which include tangential inlets, boundary of cylinder and large cone section, and the boundary of large cone section and fine cone section, are analyzed and recognized, based on Discrete Phase Model (DPM). Erosion of the revised hydrocyclone is obviously improved and the separation efficiency is enhanced by CFD analysis. At the same time, characteristic of pressure was analyzed.

Sign in / Sign up

Export Citation Format

Share Document