• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.101-102
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• 2023

This study aims to mix the base concrete by mixing latex to improve the durability performance to reduce the composite deterioration of the base concrete. Latex fiber has high resistance to freezing and thawing, adhesion, and deicing agent (calcium chloride), and it is used to secure long-term durability to reduce cracking and compound deterioration of concrete. In addition, through experiments, we are trying to find ways to improve the strength of concrete by studying the mixing of the appropriate mixing ratio of latex.

• Journal of the Korean Society of Combustion
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• v.16 no.4
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• pp.8-15
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• 2011

The present study investigates the combustion phenomena in a sludge incinerator using experimental and numerical method. The temperature and gas concentration were measured at 33 points during operation of the incinerator in order to assess the mixing and combustion characteristics. Numerical simulation was also carried out using a commercial CFD code. Simplified inlet conditions were introduced in oder to predict the bulk solid combustion and the diffusion of the volatile matter released by pyrolysis of sludge. The experimental results showed that the combustion process is extremely inhomogeneous. Large variations were observed in the temperature and gas concentrations in the freeboard of the incinerator due to poor mixing performance between the air and the combustibles, which is caused by massive and bulk generation of volatile matter by fast pyrolysis of sludge particles. The boundary condition of the CFD simulation was found effective in predicting the poor mixing and combustion performance of the reactor.

• 한국가시화정보학회:학술대회논문집
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• 2002.11a
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• pp.45-48
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• 2002

To investigate the flow related to the mixing, micro PIV measurements were performed in the middle plane of the channel. A passive micro mixer analyzed in this work has been designed in the shape of a three-dimensional microchannel and fabricated with PDMS molding process by KAIST. The mixing performance was evaluated for different flow rates using phenolphthalein and sodium hydroxide solutions. Results show that mixing is enhanced by the increase of flow rate, which yields stronger secondary flows with helical streamlines.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.173-174
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• 2022

In this study, the mixing performance of concrete was studied by setting the chemical admixture and mixing time as variables. As a result of the indoor experiment and batch plant review, the mixing time reduction performance was confirmed when the PC-based admixture A was used.

• 한국전산유체공학회:학술대회논문집
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• 2007.10a
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• pp.49-55
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• 2007

The quality of chaotic mixing in three-dimensional micro channel flow has been numerically studied using Fractional-step method (FSM) and particle tracking techniques such as $Poincar{\acute{e}}$ section and Lyapunov exponents. The flow was driven by pressure distribution and the chaotic mixing was generated by applying alternating current to electrodes embedded on the bottom wall at a first half period and on the top wall at a second half period. The equations governing the velocity and concentration distributions were solved using FSM based on Finite Volume approach. Results showed that the mixing quality depended significantly on the modulation period. The modulation period for the best mixing performance was determined based on the mixing index for various initial conditions of concentration distribution. The optimal values of modulation period obtained by the particle tracking techniques were compared with those from the solution of concentration distribution equation using FSM and CFX software and the comparison showed their good match.

• Journal of the Korea Institute of Building Construction
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• v.15 no.3
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• pp.351-357
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• 2015

Fiber reinforced concrete (FRC) has been successfully used to enhance the flexural toughness of concrete. As fibers are randomly oriented in FRC, they sometimes produce clumps that reduce the mechanical performance, and a properly chosen mixing protocol can be a way to minimize this problem. In this research, the effects of mixing method on the mechanical properties of FRC were investigated. The compressive strength, flexural strength, and flexural toughness were measured using three different mixing methods. It was shown from the results that the compressive strength and peak flexural load were not affected by changes in mixing method. However, in terms of flexural toughness, the changes in mixing method clearly affected the flexural toughness of FRC. The truck-mixed FRC outperformed two pan-mixed FRCs.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.4
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• pp.531-538
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• 2022

In this study, the self-healing hybrid capsules were prepared, were mixed with 3 %, 5 %, and 7 % based on cement mass. The healing performance were evaluated according to mixing ratio self-healing hybrid capsule. As a result of the experiment, it was found that the crack healing performance improved as the mixing rate of the self-healing hybrid capsule increased, but the quality performance tended to decrease. Therefore, it is judged that using the mixing ratio of the hybrid capsule within 5 % reduces the quality performance to within about 10 % and secures about 90 % or more of the healing performance.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.10a
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• pp.377-382
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• 1995

An evaluation method of spacer grid thermal mixing performance in rod bundles is suggested based on hydraulic tests in a single phase flow. Heat transfer correlation was derived by the analogy between momentum and heat transfer. Three of major factors, such as blockage ratio of spacer grid, convective flow swirling, and turbulent intensity, were found to be significantly influential to the spacer grid thermal mixing performance. Local heat transfer near spacer grid was predicted for the hydraulic test of 6 ${\times}$ 6 rod bundles with neighboring different spacer grids.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.30-31
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• 2016

Recently in the construction site is required various performance of mortar to deal with reliability, economy. Especially of environment-friendly, saving resources and high performance of mortar it began to require improvement of performance. Therefore, in this study, a series of tests was designed to develop a using mud flat mortar in view of the high absorption rate of tidal flats, to fix the water cement ratio to 70%. The mixing ratio were 10:0, 9:1, 8:2, 7:3, 6:4, 5:5, 4:6 of fine aggregate and mud flats. Compared the flow value, chloride content, compressive strength, tensile strength, and workability of fine aggregate the substituted mud flat mortar and basic cement mortar, present the basic data on the characteristics and effects of mud flat mortar.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.70-71
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• 2019

Interest in indoor air quality is increasing day by day due to various reasons such as industrial development. Because redmud, an industrial subsidiary, contains titanium dioxide, this study evaluated self-consolidation performance with Slump Flow Test, J-Ring Test, and L-Box Test by mixing redmud in a mixture of ultra-high performance concrete, and sought the optimal combination with high flowability. In addition, the UHPC mixing experiment with photocatalyst was conducted, and the photocatalyst was replaced by the weight ratio of cement and the redmud by the weight ratio of fine aggregate and mixed with the concrete mixture.