• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.2
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• pp.183-190
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• 2005

In the process of ice-slurry making, ice adhesion on cooling wall or in narrow flow Path disturbs continuous ice formation. In this study, the effect on the ice adhesion to cooling surface by some freezing experiments was investigated, quantitatively. Three types of solutions were frozen in various coating vessels with stirring. In the experiment, the ice adhesion between cooling wall and Ice-slurry was evaluated by measuring stirring power. From the result, the stirring power of slurry mixture in PTFE-coating vessel was smaller than those in PE-coating, PFA-coating and bare SUS vessel. Especially, in EG H PG 1.S/ HD 1.5 mass$\%$ solution, the stirring power in the PE-coating vessel was smaller than that in the PFA-coating or SUS vessel.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2008.11a
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• pp.43-47
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• 2008

CWSII method was developed to overcome the problems of frequent occurrence in the application of existing downward construction methods, especially in the case of using slurry wall instead of SCW or CIP as a retaining wall. By the improvements in connecting steel beams with the wall, CWSII method is able to ensure the settlement of a steel beam and the diaphragm effect of a slab while reducing the degree of difficulty and the term of works and the cost of construction. As the desired results, CWS method can be applied as a practical downward construction method regardless of the type of retaining wall. In this paper, besides the concept and features of CWSII method, it can be seen that the method can provide reliable and economical performances by comparing with existing methods.

• Journal of the Korean Geotechnical Society
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• v.18 no.4
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• pp.239-248
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• 2002

Bentonite slurries in a slurry wall construction must fulfill a stabilizing function by forming impermeable membrane (surface cake and penetrated cake) on the excavated soil faces. Thus problems are occurring in practice for the construction of diaphram walls and cut-off walls with a low permeability for wastes disposal areas in some deep excavations or different grounds. In this paper, the fundamental mechanics of fluid loss and filter cake formation in various soil beds are investigated using large scale laboratory apparatus. The sealing efficiency of filter cake from the large scale tests and the significance of fluid loss in a slurry trench are utilized for practical situation as a recommended design procedure.

• Journal of the Korean Geotechnical Society
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• v.29 no.6
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• pp.5-17
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• 2013

Slug tests can be adopted to estimate hydraulic conductivity of the slurry trench wall backfill for its abilities to reflect the in-situ performance of the construction. A comprehensive three-dimensional numerical model is developed to simulate the slug test in a slurry trench wall considering the presence of bentonite cake on the interface boundaries between the wall and the surrounding soil formation. Influential factors such as wall width (i.e., proximity of wall boundary), well deviation, vertical position of well intake section, compressibility of wall backfill, etc. are taken into account in the model. A series of simulation results are examined to evaluate the bentonite cake effect in analyzing practical slug test results in the slurry trench wall. The results show that the modified line-fitting method can be used without any correction factor for the slug test in the slurry trench wall with the presence of bentonite cake. A case study is reanalyzed with the assumption of existing bentonite cake. The results are compared with the previously reported results by the approaches assuming no bentonite cake (constant-head boundary) or upper-bound solution (no-flux boundary). The case study demonstrates the bentonite cake effect and the validity of the modified line-fitting method in the estimation of the hydraulic conductivity of the slurry wall backfill.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.5D
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• pp.499-505
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• 2012

As the excavation depths during excavation works in urban sites are getting deeper and bigger, It is necessary to study for the improvements to solve the problems in the excavation processes. This research deals with the excavation method that can not only minimize the effect on the surrounding constructions, but also shorten the construction period of the excavation work. For this research, there have been an extensive literature review of the bibliographic data about Slurry Wall Method, which is recognized around the world, and the analysis of the major problems in the existing ineffective construction step. These efforts led to the technical improvements. Accordingly, a new construction method applied with the new technical factors has been suggested, and it was possible to compare Slurry Wall Method with the construction method and analyze them on the base of the examples using the suggested method. This new method decreased the excavation period by 15 days. It took only 33days to finish the excavation work, as compared to 48 days that can be seen on the pre-modification schedule. Furthermore, the suggested method in this research is safer, more economically feasible, and better for the environment than Slurry Wall Method. It will contribute to shortening the construction period of Slurry Wall Method in the end.

• Proceedings of the Korean Geotechical Society Conference
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• 1998.10a
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• pp.97-104
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• 1998

• Journal of Mechanical Science and Technology
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• v.14 no.9
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• pp.997-1004
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• 2000

The experiments were conducted by using water and paraffin slurry to investigate the effect of a chip spacing in the multichip module on the cooling characteristics from an in-line $4{\times}3$ array of discrete heat sources which were flush mounted on the top wall of a channel. The experimental parameters were chip spacing in a multichip module, heat flux of simulated VLSI chip, mass fraction of paraffin slurry, and channel Reynolds number. The removable heat flux at the same chip surface temperature decreased as the chip spacing decreased at the first and fourth rows. The local heat transfer coefficients for the paraffin slurry were larger than those for water, and the chip spacing on the local heat transfer coefficients for paraffin slurry influenced less than that for water. The enhancement factor for paraffin slurry showed the largest value at a mass fraction of 5% regardless of the chip spacing, and the enhancement factors increased as the chip spacing decreased. This means that the paraffin slurry is more effective than water for cooling of the highly integrated multichip module.

• Geotechnical Engineering
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• v.7 no.3
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• pp.43-50
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• 1991

To analyze the effects of ground water levels and external loads on the stability of a Dia- phragm wall, the three models of Bell, Piaskowski/kowalewski, and Washbourne were modified and extended to develop a new program SL3D. Comparing to the other two models, Washbourne's model shows the stability in on safes at the beginning of the excavation and increase as the excavation continue . Also the effects of various design factors, such as the density of slurry, ground water levels, the friction angle of soil, external loads and the length of trench, have been analyzed and a nomogram was developed.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.984-989
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• 2009

The present study has been conducted to predict the temperature distribution in the core of the scraper type ice generator. The analytic model was simplified as the flow in the annular type cylinder, which had an inside wall moving in axial direction due to the rotation of screw and a fixed outside wall. The governing equations were arranged by the method of separation of variables. The results corresponded to the exact solutions of the Bessel function. The qualitative results such as general characteristics of heat transfer in annulus flow from outer cylinder wall to the inside wall were obtained. However the amount of the heat transfer was underestimated as low as $1/5{\sim}1/6$ of the designed value.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.12
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• pp.1063-1070
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• 2002

To resist ice adhesion on cooling wall is concerned to continuous ice formation in thermal storage system. In this study, ice slurries were formed with two ecological aqueous solution, one is ethanol+silanol and the other is propylene glycol+silanol. By freezing under stirring the solution of $300m\ell$ in a stainless steel vessel which was immersed and cooled in a temperature controlled bath, the shape of ice slurry and the strength of ice adhesion on wall was observed with measuring the temperature and stirring load variation. As the concentration is smaller and the supercooling degree is larger, the ice adhesion is easy to occur. When the stirring load is larger than$ 2.1\times10^{-5}W$, the ice adhesion occurred.