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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.

The temperature boundary condition of simulation results are then entered in the CFD (Computer Fluid Dynamics) software PHOENICS to calculate internal temperature and mechanical property of the beam.
Numerical Simulation Model This paper uses Fire Dynamics Simulation (FDS) software to analyze thermal flow field of fire field, and then enter the temperature boundary conditions of simulation result in the thermal flow computation software PHOENICS to calculate temperature and mechanical properties inside the beam, in order to investigate variations in temperature and mechanical properties in the beam after undergoing a fire.
Figure 2 is a 3D dynamic simulation transient of combustion in the fire field created by FDS.
Initial temperature of the beam is set as 23℃, iteration as 100 times, and total simulation time as 12 hours.
Concrete Compressive Strength Simulation Discussion.

,LTD, China albj86868@163.com, b498959126@qq.com, c1020066580@qq.com Keywords: Double-channel with double-suctionpump, Impeller, Volute, Matching Abstract.In order to study the matching optimization of the impeller and volute as well asthe flow characteristics ofdouble-channel with double-suction pump ,this paper based on CFD performance prediction method uses the same impeller to match the volute with different base diameters, guaranteeing the volute inlet width, flow cross-sectional area, and tongue position unchanged .The calculation results show that scheme A with the largest volute base diameter can not only achieve theexcellent energy characteristics and the velocity-pressure uniform distributions, but also the exchange of the fluid energy is more sufficient in the volute.
Because of the above reasons, this paper based on CFD performance prediction method and predecessors' research results, using the same impeller to match different base diameter volutes,study the influence of different base diameter volutes for the internal flow characteristics of the double-channel with double-suction pump.
As can be seen from the Q-H curve, the changingtendency of the simulation and experimental values are basically the same.
In the optimum condition point, the simulation head is 12m, the experimental head is 11.74m.The relative error of the simulation and experimental values is 2.3%.
From the Q-η curve can be seen, the simulation value is slightly higher than the experimental value, which is due to the numerical simulation not considering the pump volume losses and the friction losses between the water and the plate, etc.

Effect of groove on performance of splicing fiber in air splicer Zhenyu Wu1, a, Fangyuan Tian1,b and Xudong Hu1,c 1 Zhejiang Provincial Key Lab of Modern Textile Machinery, Zhejiang SCI-Tech University, Hang zhou, China azjuwuzhenyu@gmail.com, blaotian0329@163.com, c xdhu@zstu.edu.cn Keywords: splicing; simulation; axial velocity; pressure Abstract.
The result of simulation and experimental shows that: with the increase of inlet pressure, the rotational velocity and axial velocity of air flow also increase for the without groove case.
CFD Model Description Chamber’s Geometry.
The simulation model of chambers is established.
Air Flow in a Pneumatic Splicer by CFD.

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.

For these reasons, the numerical simulation based on the Computational Fluid Dynamics (CFD) is applied widely to investigate the flow character in the precalciner.
In the present work, CFD numerical simulations of three-dimensional turbulent flow in DD-precalciner are studied.
To simulation numerically, using Gambit software (preprocessor of Fluent software) to mesh, as shown in Fig. 3.
Boundary Conditions and Numerical Methods The boundary values in simulation are determined by the thermal data of cement plant with the capacity of the 5000t/d.
Conclusions This paper presented numerical simulation of the two-phase flow in DD precalciner based on Fluent software.

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.

Aravind C.V. et al. [9] conducted geometry modeling and simulation analysis using the software in MATLAB/SIMULINK platform.
Yang Sun and Liang Zhang [15] utilized a model of horizontal axis wind turbine Phase VI rotor in the prediction of power coefficient using the commercial CFD FLUENT 6.2.
Korean researchers Nak Joon Choi et al. [14] performed BAWT simulation using the commercial CFD Solver ANSYS software.
N, CFD study of a Darrieus vertical axis wind turbine, Proceedings of the 2012 ASEE North Central Section Conference (2012)
[14] Nak Joon Choi, Sang Hyun Nam, Jae Sung Kim, Sang Min Lee, Kyung Chun Kim, CFD study on power output and flow characteristics of 110 kW class BAWT, paper presented at International Conference on High Performance Computing and Simulation (2011) 859-864

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.

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