Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 11 of 11

Full-Text Articles in Entire DC Network

Modeling And Simulation Of Sofc System With Heat Transfer Among Bop Components, Ling Hong, Rongmin Wu, Jianwu Zhou, Tian Xia, Xiaojie Li, Pengjie Tian, Hao Peng, Chunhui Shou Jul 2022

Modeling And Simulation Of Sofc System With Heat Transfer Among Bop Components, Ling Hong, Rongmin Wu, Jianwu Zhou, Tian Xia, Xiaojie Li, Pengjie Tian, Hao Peng, Chunhui Shou

Journal of System Simulation

Abstract: High temperature solid oxide fuel cell (SOFC) is a high temperature and efficient hydrogen-electric conversion device. Its high temperature operating environment puts forward higher requirements for thermal insulation of stack and balance of plants(BoP) in the system. In this paper, a lumped SOFC system model is established based on the thermal efficiency-heat transfer unit number method (ε-NTU method), in combination with limited measurable parameters for high-temperature system.Quantitative analysis of components temperature and heat transfer among components can be achieved by heat exchange simulation between components and BoP hot-box environment. A simple feedback controlleris designed for system self-starting and operation. …


Research And Simulation Of Cross Flow Heat Exchanger, Chengyun Wu, Guangwen Wang, Geping Li, Xudong Xin Aug 2020

Research And Simulation Of Cross Flow Heat Exchanger, Chengyun Wu, Guangwen Wang, Geping Li, Xudong Xin

Journal of System Simulation

Abstract: Based on cell concept, the lumped parameter method was applied and the parameters in single heat exchanger cell were deduced. Thereafter 1, 4, 9,100 cells heat exchanger simulation model was set up and the simulation error and its influencing factors were analyzed. To simplify the algorithm and increase the calculation speed, as well as improve the accuracy of cross flow heat exchanger, the simplified heat exchanger model was proposed and reviewed. The research results show that the calculation of simplified heat exchanger is precise and the algorithm is simple. The model could be widely applied in cross flow heat …


Numerical Simulation Of Hot And Cold Fluids Mixing In A Tee-Junction, Wenli Wei, Yunfei Hong, Shipeng Shao, Yuling Liu Jul 2020

Numerical Simulation Of Hot And Cold Fluids Mixing In A Tee-Junction, Wenli Wei, Yunfei Hong, Shipeng Shao, Yuling Liu

Journal of System Simulation

Abstract: Flow and heat transfer model in tee junction was established and the 3D RNG k-ε turbulence model was completed to simulate the process of mixing and capture the information of velocity and temperature. The simulation results and measured data of the mean value of velocity and temperature were analyzed and compared, and are in a good agreement, which indicates that the RNG k-ε model combined with the heat transfer model can well simulate the hydraulic characteristics and heat transfer mechanism of hot and cold fluids in a tee junction. Furthermore, the upstream segment of a tee junction has two …


Fluid Flow, Heat And Mass Transfer In Hot Dip Galvanizing Bath, Shouqun Sun, Zhongshuang Wei, Huayang Lu Jun 2020

Fluid Flow, Heat And Mass Transfer In Hot Dip Galvanizing Bath, Shouqun Sun, Zhongshuang Wei, Huayang Lu

Journal of System Simulation

Abstract: Zinc dross is produced inevitably as a metallurgical phenomenon of continuous hot galvanizing process, and the quality of galvanizing is affected. The phenomenon is closely related to the physical field of molten zinc and more surface defects are easily produced if the zinc dross removal process is improperly handled. By constructing a three-dimensional viscous standard k-ε two equation turbulence model, the fluid flow, heat and mass transfer law and the distribution regularities of flow vortex were obtained under the specific initial conditions and boundary conditions. The simulation results of the observation points are basically in agreement with the experimental …


Heat Transfer Simulation Of Vehicle Heat Exchanger In Plateau Environment, Xu Xiang, Wenchao Suo, Dingfu Yang, Surong Dong Jan 2019

Heat Transfer Simulation Of Vehicle Heat Exchanger In Plateau Environment, Xu Xiang, Wenchao Suo, Dingfu Yang, Surong Dong

Journal of System Simulation

Abstract: The effect of heat transfer caused by plateau environment in vehicle heat exchanger was investigated. The heat transfer equation for heat exchanger was modified by introducing air parameters at different altitudes. A heat transfer modeling approach for vehicle heat exchanger was proposed by using the thermal network method. The heat transfer effect of the plateau and the flow state of fluid medium were analyzed in the vehicle heat exchanger by using the simulation software FlowMaster. Simulation results show that the decrease of pressure and density of air in altitude was the primary cause to heat transfer ability. …


Comparison Of Models For Mixture Transport Properties For Numerical Simulations Of Ablative Heat-Shields, Hicham Alkandry, Iain D. Boyd, Alexandre Martin Jan 2013

Comparison Of Models For Mixture Transport Properties For Numerical Simulations Of Ablative Heat-Shields, Hicham Alkandry, Iain D. Boyd, Alexandre Martin

Mechanical Engineering Faculty Publications

The goal of this study is to evaluate the effects of different models for calculating the mixture transport properties on flowfield predictions of ablative heat-shields. The Stardust sample return capsule at four different trajectory conditions is used as a test case for this study. In the first part of the study, the results predicted using Wilke's mixing rule with species viscosities calculated using Blottner's curve fits and species thermal conductivities determined using Eucken's relation are compared to the results obtained using Gupta's mixing rule with collision cross-section (CCS) data. The Wilke/Blottner/Eucken model overpredicts the heat transfer to the surface relative …


Multi-Dimensional Modeling Of Charring Ablators, Haoyue Weng, Huaibao Zhang, Ovais U. Khan, Alexandre Martin Jun 2012

Multi-Dimensional Modeling Of Charring Ablators, Haoyue Weng, Huaibao Zhang, Ovais U. Khan, Alexandre Martin

Mechanical Engineering Faculty Publications

Re-entry of a spacecraft occurs at the hypersonic regime where the flow field is extremely complex: high temperature gradients occurring in the shock-layer region ionize and dissociate the air. Even if a large portion of heat generated during this process is convected away in the surrounding air, a fraction of it is still transferred to the vehicle. Therefore, it is important to protect the vehicle with a suitable kind of shielding. Of the many techniques available today, use of ablative material is gaining popularity. The basic idea behind an ablating heat shield is that the energy incident on the spacecraft …


Modeling Of Heat Transfer Attenuation By Ablative Gases During The Stardust Re-Entry, Alexandre Martin, Iain D. Boyd Jan 2012

Modeling Of Heat Transfer Attenuation By Ablative Gases During The Stardust Re-Entry, Alexandre Martin, Iain D. Boyd

Mechanical Engineering Faculty Publications

The great majority of modern space vehicles designed for planetary exploration use ablative materials to protect the payload against the high heating environment experienced during re-entry. In order to properly model and predict the aerothermal environment of the vehicle, it is imperative to account for the gases produced by ablation processes. In the case of charring ablators, where an inner resin is pyrolyzed at a relatively low temperature, the composition of the gas expelled into the boundary layer is complex and may lead to thermal chemical reactions that cannot be captured with simple flow chemistry models. In order to obtain …


The Analysis Of Heat Transfer In A Gas-Gas Heat Exchanger Operated Under A Heat-Recirculating Mode, Mariusz Salaniec, Wojciech M. Budzianowski Jan 2011

The Analysis Of Heat Transfer In A Gas-Gas Heat Exchanger Operated Under A Heat-Recirculating Mode, Mariusz Salaniec, Wojciech M. Budzianowski

Wojciech Budzianowski

The present paper presents the analysis of heat transfer in a gas-gas heat exchanger operated in a heat-recirculating mode.


Vascular Countercurrent Network For 3d Triple-Layered Skin Structure With Radiation Heating, Xiaoqi Zeng Jan 2011

Vascular Countercurrent Network For 3d Triple-Layered Skin Structure With Radiation Heating, Xiaoqi Zeng

Doctoral Dissertations

Heat transfer in living tissue has become more and more attention for researchers, because high thermal radiation produced by intense fire, such as wild fires, chemical fires, accidents, warfare, terrorism, etc, is often encountered in human's daily life. Living tissue is a heterogeneous organ consisting of cellular tissue and blood vessels, and heat transfer in cellular tissue and blood vessel is quite different, because the blood vessels provide channels for fast heat transfer. The metabolic heat generation, heat conduction and blood perfusion in soft tissue, convection and perfusion of the arterial-venous blood through the capillary, and interaction with the environment …


Online Tuning Of Set-Point Regulator With A Blending Mechanism Using Pi Controller, Engi̇n Yeşi̇l, Müjde Güzelkaya, İbrahi̇m Eksi̇n, Ö. Aydin Teki̇n Jan 2008

Online Tuning Of Set-Point Regulator With A Blending Mechanism Using Pi Controller, Engi̇n Yeşi̇l, Müjde Güzelkaya, İbrahi̇m Eksi̇n, Ö. Aydin Teki̇n

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a new control structure that exploits the advantages of one degree of freedom (1-DOF) and two degree of freedom (2-DOF) control structures with an online tuned set-point regulator with blending mechanism (SPR-BM) is proposed. In this structure, the filtered output of the reference and the pure reference signals are blended so that the overall performance of the system is ameliorated with respect to load disturbance rejection and set-point following. Internal Model Control (IMC) based PI controller is used as the primary controller and the blending dynamics are determined with the aim of producing a system output that …