• Proceedings of the SAREK Conference
• /
• 2004.06a
• /
• pp.17-17
• /
• 2004

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.12
• /
• pp.723-729
• /
• 2016

This study compared fin-tube and parallel-flow heat pipes for their sensible heat exchange rate, heat recovery amount, and air-side pressure drop. Tests were done with different refrigerant charging rates of 40-60% vol. and air flow rates of 300-1,400. The sensible heat exchange rate was highest for both types of heat pipes at a working fluid charge of 40% vol. and low flow rate. For the parallel-flow heat pipe, the 60% vol. charge is too high and results in a low sensible heat exchange rate. The reason is that the thicker liquid film of the tube wall deteriorates the heat transfer effect. Hence, the optimal charging rate is 40 to 50% vol. The evaporator heat pipe has a larger air-side pressure drop than the condenser section heat pipe. The reason is considered to be condensation water arising from the evaporator surface. Compared to the fin-tube heat pipe, the parallel-flow heat pipe showed better performance with a working fluid charging rate of 48%, volume of 41%, and an air-side pressure drop about 37%.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1993.04a
• /
• pp.35-35
• /
• 1993

• Proceedings of the Korean Nuclear Society Conference
• /
• 2003.05a
• /
• pp.149.2-149.2
• /
• 2003

• 유체기계공업학회:학술대회논문집
• /
• 2005.12a
• /
• pp.722-731
• /
• 2005

• Kyungpook Mathematical Journal
• /
• v.14 no.1
• /
• pp.15-21
• /
• 1974

• 한국전산유체공학회:학술대회논문집
• /
• 2006.05a
• /
• pp.372-375
• /
• 2006

• 한국전산유체공학회:학술대회논문집
• /
• 2006.05a
• /
• pp.81-82
• /
• 2006

• Journal of Electrical Engineering and Technology
• /
• v.1 no.4
• /
• pp.455-460
• /
• 2006

This paper presents the convergency property of the Auxiliary Problem Principle when it is applied to large-scale Optimal Power Flow problems with Distributed or Parallel computation features. The key features and factors affecting the convergence ratio and solution stability of APP are also analyzed.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.31 no.2
• /
• pp.1-9
• /
• 2003

In the present study, a 3-D Parallel DSMC method in developed on unstructured meshes for the efficient simulation of rarefied gas flows. Particle tracing between cells in achieved based on a linear shape function extended to three dimensions. For high parallel efficiency, successive domain decomposition is applied to achieve load balancing between processors by accounting for the number of particles. A particle weighting technique is also adopted to handle flows containing gases of significantly dirrerent number densities in the same flow domain. Application is made for flow past a 3-D delta wing and the result is compared with that from experiment and other calculation. Flow around a rocket payload at 100km altitude is also solved and the effect of plume back flow from the nozzle in studied.