Self-Localization for Robot Based on the White Line

By numerical simulation computation, after passing the pulsating flow, enhanced heat transfer mechanism in spirally fluted tubes was researched. Numerical result shows that pulsating flow can cause the outlet pressure to fluctuate cyclical and the extent of fluctuation increases with the pulsating flow frequency. The pulse flowing can make the fluid generate the whirlpool nearby the spirally fluted tubes and the phenomenon of periodic production, drift, and fall-off appears. Because of the vortex, the fluid motion and relative motion are enhanced. The pulse flowing can improve the coordination level between velocity and temperature, thus has strengthened the heat transfer effect.

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Calculation and Design Method Study of the Coil-Wound Heat Exchanger

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1008-1009.850 ◽

2014 ◽

Vol 1008-1009 ◽

pp. 850-860 ◽

Cited By ~ 3

Author(s):

Zhou Wei Zhang ◽

Jia Xing Xue ◽

Ya Hong Wang

Keyword(s):

Heat Transfer ◽

Numerical Simulation ◽

Heat Exchanger ◽

Design Method ◽

Fluid Velocity ◽

Exchange Process ◽

Three Dimensional ◽

Simulation Method ◽

Physical Parameters ◽

Numerical Result

A calculation method for counter-current type coil-wound heat exchanger is presented for heat exchange process. The numerical simulation method is applied to determine the basic physical parameters of wound bundles. By controlling the inlet fluid velocity varying in coil-wound heat exchanger to program and calculate the iterative process. The calculation data is analyzed by comparison of numerical result and the unit three dimensional pipe bundle model was built. Studies show that the introduction of numerical simulation can simplify the pipe winding process and accelerate the calculation and design of overall configuration in coil-wound heat exchanger. This method can be applied to the physical modeling and heat transfer calculation of pipe bundles in coil wound heat exchanger, program to calculate the complex heat transfer changing with velocity and other parameters, and optimize the overall design and calculation of spiral bundles.

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Characteristics of Heat Transfer and Flow on a Surface With Small-Scale Concave Spherical Pits

ASME 2008 First International Conference on Micro/Nanoscale Heat Transfer, Parts A and B ◽

10.1115/mnht2008-52191 ◽

2008 ◽

Author(s):

J. S. Wang ◽

Y. Qiu ◽

L. Y. Li

Keyword(s):

Heat Transfer ◽

Numerical Simulation ◽

Small Scale ◽

Heat Transfer Mechanism ◽

Transfer Enhancement ◽

Special Effect ◽

Turbulent Drag Reduction ◽

Turbulent Drag ◽

Simulation Results ◽

Turbulent Coherent Structure

Small-scale concave spherical pits, which have a special effect on heat transfer enhancement and turbulent drag reduction, are investigated by numerical simulation in detail. Two kinds of small-scale concave pits structures are designed on surface of a plate, which are located in the bottom of a rectangle channel. The characteristics of heat transfer and flow in channel are investigated and compared with a same channel with plate bottom by means of LES. Flow structure and temperature distribution near the pits are analyzed. The numerical simulation results indicate that the concave spherical pits disturb the flow field and vortex is induced by the pits. The turbulent coherent structure is affected by the induced vortex. The numerical simulation indicates that small scale pit can generate the vortex in couple. The range of vortex is accord with the array of small scale pit. The small scale pit can enhance the intensity of vortex. As a result, the temperature field near the pit is changed with generation of the vortex. The heat transfer mechanism on plate with small scale concave spherical pit is summarized.

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Numerical simulation of vapor bubble growth on a vertical superheated wall using lattice Boltzmann method

International Journal of Numerical Methods for Heat &amp Fluid Flow ◽

10.1108/hff-08-2013-0263 ◽

2015 ◽

Vol 25 (5) ◽

pp. 1214-1230 ◽

Cited By ~ 7

Author(s):

Tao Sun ◽

Weizhong Li ◽

Bo Dong

Keyword(s):

Heat Transfer ◽

Numerical Simulation ◽

Phase Change ◽

Lattice Boltzmann Method ◽

Lattice Boltzmann ◽

Nucleate Boiling ◽

Numerical Results ◽

Heat Transfer Mechanism ◽

Content Type ◽

Boltzmann Method

Purpose – The purpose of this paper is to test the feasibility of lattice Boltzmann method (LBM) for numerical simulation of nucleate boiling and transition boiling. In addition, the processes of nucleate and transition boiling on vertical wall are simulated. The heat transfer mechanism is discussed based on the evolution of temperature field. Design/methodology/approach – In this paper, nucleate boiling and transition boiling are numerically investigated by LBM. A lattice Boltzmann (LB) multiphase model combining with a LB thermal model is used to predict the phase-change process. Findings – Numerical results are in good agreement with existing experimental results. Numerical results confirm the feasibility of the hybrid LBM for direct simulations of nucleate and transition boiling. The data exhibit correct parametric dependencies of bubble departure diameter compared with experimental correlation and relevant references. Research limitations/implications – All the simulations are performed in two-dimensions in this paper. In the future work, the boiling process will be simulated in three-dimensional. Practical implications – This study demonstrated a potential model that can be applied to the investigation of phase change heat transfer, which is one of the effective techniques for enhance the heat transfer in engineering. The numerical results can be considered as a basic work or a reference for generalizing LB method in the practical application about nucleate boiling and transition boiling. Originality/value – The hybrid LBM is first used for simulation of nucleate and transition boiling on vertical surface. Heat transfer mechanism during boiling is discussed based on the numerical results.

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Numerical Simulation of Electrohydrodynamic (EHD) Atomization in the Cone-Jet Mode

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.325-326.180 ◽

2013 ◽

Vol 325-326 ◽

pp. 180-185 ◽

Cited By ~ 2

Author(s):

Abdolkarim Najjaran ◽

Reza Ebrahimi ◽

Morteza Rahmanpoor ◽

Ahmad Najjaran

Keyword(s):

Heat Transfer ◽

Numerical Simulation ◽

Ambient Temperature ◽

Deposition Rate ◽

Low Cost ◽

High Deposition Rate ◽

Deposition Technique ◽

Enhanced Heat Transfer ◽

Ansys Fluent ◽

Set Up

Electrohydrodynamic (EHD) has been applied in many areas, such as EHD atomization, EHD enhanced heat transfer, EHD pump, electrospray nanotechnology, etc. EHD atomization is a promising materials deposition technique as it allows uniform and regular deposition, and offers a range of other advantages, such as low cost compared with other current techniques, easy set-up, high deposition rate, and ambient temperature. Simulation is carried out using ANSYS FLUENT system. The approach in this work was to simultaneously solve the coupled (EHD) and electrostatic equations. The fields of velocities and pressure, as well as electric characteristics of EHD flows, are calculated. The model does not include a droplet break-up model.

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On Structure and Heat-Transfer Mechanism for Multi-Channel Drying Cylinder of Energy-Saving Type

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.236-238.1326 ◽

2011 ◽

Vol 236-238 ◽

pp. 1326-1331

Author(s):

Ji Xian Dong ◽

Zhen Zhang ◽

Rui Dang ◽

Jian Xiao Lu

Keyword(s):

Heat Transfer ◽

Numerical Simulation ◽

Energy Saving ◽

Transfer Mechanism ◽

Heat Transfer Mechanism ◽

Simulation Approach ◽

Water Condensation ◽

Heat Transfer Efficiency ◽

Drying Cylinder ◽

Theoretical Results

In this paper, the authors explore the structure and operating mechanism of the energy- saving type multi-channel drying cylinder, which can be used in papermaking machine dryer section to effectively reduce the amount of condensate water, and tackle such problem as the water condensation in drying cylinder. This paper theoretically expatiates upon the heat transfer mechanism of the multi-channel drying cylinder of energy-saving type and verifies the theoretical results with numerical simulation approach, which proves that energy-saving type multi-channel drying cylinder can effectively improve the heat transfer efficiency, and increase the productivity of the papermaking machine while the drying cylinder is featured by high cost in manufacturing and non-uniformity in surface temperature because of its peculiarity of configuration, which need to be investigated and improved.

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Entropy Study on the Enhanced Heat Transfer Mechanism of the Coupling of Detached and Spiral Vortex Fields in Spirally Corrugated Tubes

Heat Transfer Engineering ◽

10.1080/01457632.2020.1800251 ◽

2020 ◽

pp. 1-15

Author(s):

Wei Wang ◽

Kang Fu ◽

Yaning Zhang ◽

Yufei Tan ◽

Bingxi Li ◽

...

Keyword(s):

Heat Transfer ◽

Transfer Mechanism ◽

Heat Transfer Mechanism ◽

Enhanced Heat Transfer ◽

Spiral Vortex

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Introduction

Enhanced Heat Transfer Mechanism of Nanofluid MQL Cooling Grinding - Advances in Chemical and Materials Engineering ◽

10.4018/978-1-7998-1546-4.ch001 ◽

2020 ◽

pp. 1-19

Keyword(s):

Heat Transfer ◽

Minimum Quantity Lubrication ◽

Current Status ◽

Exploratory Research ◽

Heat Transfer Mechanism ◽

Enhanced Heat Transfer ◽

Minimum Quantity ◽

Heat Transfer Capacity ◽

Minimal Quantity ◽

Scientific Significance

This chapter introduces the application background and characteristics of five kinds of grinding processing methods, briefly describes the enhanced heat transfer mechanism and tribological properties of nanofluids, and points out that nanofluids minimum quantity lubrication (NMQL) solves the technical bottleneck, namely minimum quantity lubrication (MQL) heat transfer capacity is insufficient and opening a new path for application of MQL to grinding process. The current status of exploratory research on the mechanism of minimum quantity lubrication grinding using nanofluids as cooling lubricants is analyzed. The research characteristics of the new green NMQL grinding technology are described, and the chapter puts forward some key problems such as the heat transfer enhancement process of NMQL, the anti-friction and anti-wear tribological mechanism of nanoparticles, and the controlled transport strategies of minimal quantity of lubricating droplets. It will be of great scientific significance and pragmatic value to perfecting NMQL grinding technical system.

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