• Journal of the Korean Geotechnical Society
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• v.30 no.4
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• pp.93-99
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• 2014

Use of geothermal energy has been increased for its economical application and environmentally friendly utilization. Particularly, for energy piles, a spiral coil type ground heat exchanger (GHE) is more preferred than line type GHEs such as U and W shaped GHEs. A PHC energy pile with spiral coil type GHE was installed in an area of partially saturated dredged soil deposit, and a thermal response test (TRT) was conducted for 240 hours under a continuous operation condition. Besides, remolded soil samples from different layers were collected in the field, and soil specimens were reconstructed according to the field ground condition. Non-steady state probe methods were conducted in the lab, and ground thermal conductivity and thermal diffusivity were measured for the different soil layers. An equivalent ground thermal conductivity was calculated from the lab test results and it was compared with the field TRT result. The difference was less than 5%, which advocates the use of an equivalent ground thermal conductivity for the multi-layered ground. Furthermore, this paper also represents an equivalent ground thermal diffusivity evaluation method which is another very important design parameter.

• Journal of the Korean Society of Marine Environment & Safety
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• v.11 no.2 s.23
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• pp.109-115
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• 2005

Hydrocyclone has been widely used for the solid-liquid separation in many industrial sites because of its comparatively preferable applications that can be applied to wide-range particle sizes. If seawater with impurities flows through pumps or heat exchanger, it might cause an decrease in the efficiency of cooling system In this paper, we have suggested some methods of separating impurities from seawater in the cooling system by using a Hydrocyclone. The effects of design factors as solid concentration, cyclone inlet pressure, flow rate and diameter of underflow on the separating performance of the Hydrocyclone were investigated The results from this study are summarized as follows: 1) In proportion to the decrease of solid concentration, the efficiency of solid-liquid separation is improved. 2) According as the cyclone inlet pressure increases the efficiency of separation is improved. Conclusively, this research suggested that the Hydrocyclone will be used as a pre-treatment system of cooling water in machines, and eventually prevent unexpected accidents in engine systems.

• Proceedings of KOSOMES biannual meeting
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• 2004.11a
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• pp.109-115
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• 2004

Hydrocyclone has been widely used for the solid-liquid separation in many industrial sites because of its comparatively preferable applications that can be applied to wide-range particle sizes. If seawater with impurities flows through pumps or heat exchanger, it might cause an decrease in efficiency of cooling system. In this paper, we have suggested some methods of separating impurities from seawater in the cooling system by using a Hydrocyclone. The effects of design factors as solid concentration, cyclone inlet pressure, flow rate and diameter of underflow on the separating performance of the Hydrocyclone were investigated The results from this study are summarized as follows: 1) In proportion to the decrease of solid concentration, the efficiency of solid-liquid separation is improved 2) According as the cyclone inlet pressure increases the efficiency of separation is improved Conclusively, this research suggested that the Hydrocyclone will be used as a pre-treatment system of cooling water in machines, and eventually prevent unexpected accidents in engine systems.