The Aerodynamic Characteristics of a Microbus

2011 ◽  
Vol 201-203 ◽  
pp. 1284-1287
Author(s):  
Xiao Ni Qi ◽  
Jian Meng ◽  
Yong Qi Liu
Keyword(s):  
Numerical Simulation ◽  
Theoretical Basis ◽  
Reliable Method ◽  
Aerodynamic Resistance ◽  
Three Dimensional ◽  
Turbulence Models ◽  
Aerodynamic Characteristics ◽  
Related Research ◽  
Flow Maps ◽  
Resistance Reduction

This work is focused on the reduction of the aerodynamic resistance of a microbus. The approach is the three dimensional (3-D) numerical simulation. The RNG k–ε turbulence models are adopted in the computation. Based on the model of SC6350 Chang’an microbus and the improved rear shape, the aerodynamic characteristics of both models at different speeds are studied. Flow maps drawn on the basis of the computed results can offer a reliable method to study the flow field around a microbus. The computed results can give a reference for study of the aerodynamic resistance reduction on a microbus for energy saving. And the results of the optimized shape can provide a theoretical basis for the related research.

scholarly journals NUMERICAL SIMULATION OF AIRFLOW AROUND VEHICLE MODELS

2018 ◽  
Vol 56 (3) ◽  
pp. 370
Author(s):  
Nguyen Van Thang ◽  
Ha Tien Vinh ◽  
Bui Dinh Tri ◽  
Nguyen Duy Trong
Keyword(s):  
Numerical Simulation ◽  
Kinetic Energy ◽  
Three Dimensional ◽  
Aerodynamic Characteristics ◽  
Aerodynamic Forces ◽  
Dissipation Energy ◽  
Ansys Fluent ◽  
Car Model ◽  
Airflow Field ◽  
Fluent Software

This article carries out the numerical simulation of airflow over three dimensional car models using ANSYS Fluent software. The calculations have been performed by using realizable k-e turbulence model. The external airflow field of the simplified BMV M6 model with or without a wing is simulated. Several aerodynamic characteristics such as pressure distribution, velocity contours, velocity vectors, streamlines, turbulence kinetic energy and turbulence dissipation energy are analyzed in this study. The aerodynamic forces acting on the car model is calculated and compared with other authors.

scholarly journals Numerical Simulation of the Flow Through the Return Channel of Multi-Stage Centrifugal Compressors

1998 ◽  
Author(s):  
L. J. Lenke ◽  
H. Simon
Keyword(s):  
Numerical Simulation ◽  
Three Dimensional ◽  
Turbulence Models ◽  
Reynolds Stress Model ◽  
Secondary Flows ◽  
Low Flow ◽  
Load Range ◽  
Design Point ◽  
Multi Stage ◽  
Return Channel

The numerical simulation of the flow within a return channel is reported in this paper. The investigated return channel is typically to join the exit from one stage of a centrifugal machine to the inlet of the next stage. These channel covers the range of extremely low flow coefficients. Different 3-D calculations with two different turbulence models (low-Reynolds-number k-ϵ and explicit algebraic Reynolds stress model) at the design point and part load range show the strongly three-dimensional flow structure with secondary flows on hub and shroud of the deswirl vanes. There are also significant separations downstream of the 180°-bend at suction and pressure side of the vanes. The presented numerical results are compared with experimental data in different planes and at the vane contour. The results indicate small differences between the turbulence models in the prediction of losses, flow angles and separation behavior at design point. At off-design conditions the turbulence models begin to deviate notably in their prediction of separation.

Numerical Simulation on Aerodynamics of Ramjet Projectiles

2011 ◽  
Vol 201-203 ◽  
pp. 89-92 ◽  
Author(s):  
Jia Xian Zhang ◽  
Yan Na Wang ◽  
Rui Min Liu
Keyword(s):  
Numerical Simulation ◽  
Mach Number ◽  
Lift Coefficient ◽  
Three Dimensional ◽  
Numerical Algorithms ◽  
Aerodynamic Characteristics ◽  
Navier Stokes ◽  
Pressure Center ◽  
Complex Wave ◽  
Center Increase

Three-dimensional Reynolds-averaged Navier-Stokes simulations have been performed to explore the aerodynamic characteristics of ramjet projectiles. The turbulence model used is the RNG k-ε model. The numerical algorithms termed total variational diminishing (TVD) was adopted. The complex wave structures of ramjet projectiles with different architecture at different inflow Mach number were achieved by numerical simulation. The influence of inflow Mach number on aerodynamic characteristics and pressure center of ramjet projectiles were analyzed. Results show that lift coefficient and pressure center increase with the argument of inflow Mach number. Ramjet projectiles with different architecture have different drag coefficient trend.

Effect of the Air Duct System of a Simplified Vehicle Model on Aerodynamic Performance

2020 ◽  
Vol 17 (2) ◽  
pp. 7985-7995
Author(s):  
A. W. Huluka ◽  
C. H. Kim
Keyword(s):  
Numerical Study ◽  
Aerodynamic Resistance ◽  
Three Dimensional ◽  
Aerodynamic Characteristics ◽  
Aerodynamic Performance ◽  
Vehicle Model ◽  
Fundamental Study ◽  
Pressure Drag ◽  
Energy Efficiency Improvement ◽  
Simple Body

In this numerical study, ducted Ahmed model is used to study aerodynamic characteristics of ducted models and how ducting would contribute to the energy consumption reduction effort from aerodynamic resistance. Three-dimensional, incompressible, and steady governing equations were solved by commercial software PHOENICS (version 2018) with extended turbulent model proposed by Chen-Kim (1987). The study can be considered as a stepping stone to bring a new approach to design aerodynamically efficient vehicle by ducting target vehicles. To investigate the feasibility of the ducting for aerodynamic energy efficiency improvement, fundamental study has been conducted numerically on a simple body before applying to appropriate vehicle model. It is observed from the study that ducting would reduce over 19% of the pressure drag, to the contrary the increase in skin friction drag is noted although its significance to the total drag is very less compared to pressure drag. Therefore, study of ducting and its effect on aerodynamic performance is expected to contribute to improvement of electric vehicle aerodynamic performance.

Evaluation of RANS Models in Predicting Low Reynolds, Free, Turbulent Round Jet

2013 ◽  
Vol 136 (1) ◽  
Author(s):  
Shahriar Ghahremanian ◽  
Bahram Moshfegh
Keyword(s):  
Numerical Simulation ◽  
Boundary Conditions ◽  
Flow Behavior ◽  
Three Dimensional ◽  
Turbulence Models ◽  
Diffusion Term ◽  
Turbulent Region ◽  
Round Jet ◽  
Rans Models ◽  
Low Reynolds

In order to study the flow behavior of multiple jets, numerical prediction of the three-dimensional domain of round jets from the nozzle edge up to the turbulent region is essential. The previous numerical studies on the round jet are limited to either two-dimensional investigation with Reynolds-averaged Navier–Stokes (RANS) models or three-dimensional prediction with higher turbulence models such as large eddy simulation (LES) or direct numerical simulation (DNS). The present study tries to evaluate different RANS turbulence models in the three-dimensional simulation of the whole domain of an isothermal, low Re (Re = 2125, 3461, and 4555), free, turbulent round jet. For this evaluation the simulation results from two two-equation (low Re k-ɛ and low Re shear stress transport (SST) k-ω), a transition three-equation (k-kl-ω), and a transition four-equation (SST) eddy-viscosity turbulence models are compared with hot-wire anemometry measurements. Due to the importance of providing correct inlet boundary conditions, the inlet velocity profile, the turbulent kinetic energy (k), and its specific dissipation rate (ω) at the nozzle exit have been employed from an earlier verified numerical simulation. Two-equation RANS models with low Reynolds correction can predict the whole domain (initial, transition, and fully developed regions) of the round jet with prescribed inlet boundary conditions. The transition models could only reach to a good agreement with the measured mean axial velocities and its rms in the initial region. It worth mentioning that the round jet anomaly is still present in the turbulent region of the round jet predicted by the low Re k-ɛ. By comparing the k and the ω predicted by different turbulence models, the blending functions in the cross-diffusion term is found one of the reasons behind the more consistent prediction by the low Re SST k-ω.

The Study on the Basic Theory of Gold Seamless Pipe Welding Numerical Simulation

2013 ◽  
Vol 456 ◽  
pp. 467-470 ◽  
Author(s):  
Wen Chao Qin ◽  
Jian Ru Qi ◽  
Li Xin Wang ◽  
Wei Hong Ye
Keyword(s):  
Numerical Simulation ◽  
Theoretical Basis ◽  
Simulation Analysis ◽  
Three Dimensional ◽  
Field Analysis ◽  
Analysis Method ◽  
Seamless Pipe ◽  
Pipe Welding ◽  
Reasonable Choice ◽  
Gold Industry

Based on the theory of FEM, we have established a viable three-dimensional dynamic simulation of welding field analysis method, heat distribution with a double ellipse as a welding heat source, to establish a reasonable boundary conditions, which is a reasonable choice of welding numerical simulation provides a theoretical basis, laying the groundwork for welding numerical simulation analysis of the gold industry.

Sign in / Sign up

Export Citation Format

Share Document