Search results

Agung carried out a simulation of temperature fluctuations and stagnation in a wind tunnel [7].
Method This research was carried out using variations in air flow velocity and viscous models through a series of simulations based on the computational fluid dynamics (CFD) method.
Wind tunnel simulation data was obtained using the CFD method repeatedly based on each variation at nine different points in the test section.
Pressure drops at different inlet velocity Conclusions The CFD simulation in an open-circuit subsonic wind tunnel is to determine the uniformity of velocity mainly in the test section.
Cinar, “Design and Flow Simulation of an Open Circuit Wind Tunnel,” pp. 2–5, 2009

Coupled with the rapid development of CFD (Computational Fluid Dynamics) technology, numerical simulation for the cavitations flows, both can make up the shortcomings of theoretical analysis methods in complex cavitations problems applications and also save the cost of model test, moreover it can be accuracy, high speed, and can simulate the pattern of the flow field and get accurate flow characteristics without the impact the constraints inherent in testing.
The Physical model of simulation The simulation is for a model full-flow of the giant unit, which over-current components are: scroll, vanes, guide vanes, runner, draft tube.
Before the unsteady simulation, the standard k-ε model was used for the steady simulation, and the flow data upon steady simulation with will be as the initial conditions for the unsteady simulation.
The unsteady simulation will use the RNG k-ε model.
A CFD parametric study of geometrical variations on the pressure pulsations and performance characteristics of a centrifugal pump.

Simulations via computational fluid dynamics (CFD) have offered various insights into the flow physics of rotational aerodynamics.
However, CFD over such flows is not a straight-forward case.
While the computations of direct numerical simulations (DNS) are highly sought after, they are not realistically feasible due to the high computational overheads.
Based on this, the simulations were set to a steady state full rotation of the blade.
Sørensen, Aerofoil characteristics from 3D CFD rotor computations.

With tremendous progress of the computer science, numerical techniques like Computational Fluid Dynamics (CFD) have been used more and more widely.
And the commercial CFD software FLUENT has been used to simulate the flow field.
In the simulation, Influence of temperature is also taken into consideration.
The experiment and simulation results are listed in Table 2.
It can be seen that, simulation and experiment results are consistent well.

ANSYS and SPICE simulation results show that the proposed sensor can worked properly under 500K Pa, and the square sensing membrane of 100x100 mm 2 shows a good linearity over a pressure change ranging from 5 Pa to 500K Pa.
The total capacitors include Cfd, Cfs, Cfd and Cfb.
Main electrical parameters for SPICE simulation are shown below: channel length is 20mm, channel width is 50 mm, equivalent gate oxide thickness is 3.7 nm, channel doping density is 1.1´1015/cm2, and threshold voltage is -34.19 mV.
Fig.5 SPICE simulation results of the drain current with different pressure Summary In this paper, a floating-gate MOSFET pressure sensor with floating gate has been proposed, and the operation principle of the device in standard CMOS process has been discussed.
ANSYS and SPICE simulation results show that the proposed sensor can worked properly under 500K Pa, and the square sensing membrane of 100x100 mm 2 shows a good linearity over a pressure change ranging from 5 Pa to 500K Pa.

In the late two decades, the LBM has advanced to such an extent that it has become a versatile and competitive alternative for Computational Fluid Dynamics (CFD) in many areas [2].
The advantages of LBM compare with conventional CFD method were LBM is simple calculation procedure; it is efficient implementation for parallel computation, easy and robust handling of complex geometry and others [4].
There are various numerical simulation have been done using different thermal LB model to investigate natural convection based on their advantages of LBM [5, 6].
Shan, Simulation of Raylaigh-Bernard convection using a lattice Boltzmann method, Phys Rev E 55 (1997) 2780-2788
In Rarefied Gas Dynamics: Theory and Simulations, Progr Astronaut Aero 159 (1992) 450-458

Predictive Models for Evaluating Mobility Buses Thermal Performance Luca Evangelisti1,a, Gabriele Battista1,b Claudia Guattari1,c, Roberto de Lieto Vollaro1,d and Luciano Santarpia2,e 1Roma TRE University – Department of Engineering – Via della Vasca Navale, 62 – Rome, Italy 2”Sapienza” University of Rome, DIAEE – Sezione Fisica Tecnica, Via Eudossiana18, 00184, Rome, Italy aluca.evangelisti@uniroma3.it, bgabriele.battista@uniroma3.it, cclaudia.guattari@uniroma3.it, droberto.delietovollaro@uniroma3.it, eluciano.santarpia@uniroma1.it Keywords: Bus, Optimization, Energy, Dynamic Simulation.
In this study two models have been developed by applying the dynamic software TRNSYS, which is widely used to analyze thermal exchanges [2-9], and a CFD model able to reproduce the thermo fluid dynamic processes inside the bus.
On the other hand, considering the frequent bus stops characterized by opened doors and subsequent air changes, the effectiveness of an “air blade system” installed upon the doors has been analyzed through a CFD analysis.
Figure 3 – Air blade system A commercial mobility bus has been implemented with a CFD software, in particular some parameters have been defined: the opening and closing doors phase, which lasts for 30 seconds, the external and internal temperatures, that are set equal to 35°C and 27°C, respectively, and the air knife velocity is fixed equal to 5m/s.
The CFD simulations have been performed within a 3D domain under steady state conditions with Reynolds-averaged Navier–Stokes (RANS) equations according to the k–ε model standard.

By using CFD simulation tool FLUENT we simulate the battery transient heat transfer process and get a set of temperature profiles at the center of the battery under different discharge rates(0.5C, 1.0C, 1.5C and 2.0C) and heat dissipation conditions(h = 0W/m2∙K, 5W/m2∙K, 15W/m2∙K, 40W/m2∙K).
To adjust the internal heating rate according to the 3D fitting curves above, the user-defined function (UDF) built in CFD simulation tool FLUENT is used.
Using FLUENT software, the author comparing the results, the data obtained from the lumped parameter method coincides well with the data from simulation.
Indeed, the final temperature from the former method is between two simulation results that are the final temperature in the center and at the edge.
It is feasible to use the simulation results to guide practice or even to design battery thermal management.

In this respect, computer simulations have shown increasing potential.
For example, Guo and Liang [12] proposed a new method named “simulation in subsections, integration of the whole” to achieve the overall numerical simulation of RB heat exchanger performance.
More recently, Dong et al. [13] used a periodic flow unit duct as the simplified model of the shellside to perform numerical simulation by CFD code, FLUENT.
(a) SB Heat Exchanger (b) RB Heat Exchanger Fig. 1 Mesh of SB and RB heat exchangers Results and Discussion The temperature distribution, velocity distribution and pressure distribution of the two types of heat exchangers are analyzed by CFD.
A new numerical simulation method for rod-baffle heat exchanger.

Finally we do simulations in ANSYS.
Second is performance simulation.
The flow field of a new axial piston EHP is studied based on CFD in Ref.[11], including the models of main flow fields of the pump, numerical simulations, the velocity and pressure distribution.
Simulation and Results Simulation Conditions.
Simulations.