Student Major/Year in School
Mechanical Engineering, third year
Faculty Mentor Information
Melanie Derby, Department of Mechanical and Nuclear Engineering, Kansas State University
Abstract
Layered wicks enable passive transport of condensation out of cooling systems
Nhicolas Aponte, Jordan Morrow, Gennifer Riley, Partha Chakraborty, Melanie M. Derby
Department of Mechanical and Nuclear Engineering, Kansas State University
Cooling systems, like condensers or cooling towers of a power plant, transfer heat out of a system. The cooling process often occurs through the condensation of water, which forms a liquid film that reduces heat transfer. This problem makes cooling systems larger and more costly. One approach to this problem is drop-wise condensation in which condensed water gathers in the form of droplets which can then run off, preventing the reduction of heat transfer caused by the liquid film. For this solution to be effective in industry, a hydrophobic coating would need to last over 10 years, which is difficult to achieve. The approach studied in this work uses the capillary/surface tension forces to passively transport water, which is applicable to removing liquid films from condensers. This is investigated by using a wick, which is a structure that enables the passive transport of water. In this project, we compare wicking structures with different porosity in order to design an effective wick for industrial use. The wicks used are an array of layered spheres bridged by cylindrical columns with calculated porosity of 0.35(Wick C), 0.42(Wick B), and 0.66(Wick A). The wicks are 3-D printed onto a test plate, which allows the fabrication of complex geometries. The effectiveness of the wicks is compared using the rate-of-rise method. For this method, the wicks are lowered into a water reservoir. The interactions between the wick and the water are observed and recorded under a high speed camera. Then, the height the water rises to within the wick is compared. The wicks printed for this project outline problems we did not account for. The small pore volume of the wicks made it difficult to clean out support material after being printed. Future wicks will be designed with a greater pore volume than that of Wick C. The success of this project could improve the heat transfer in space cooling systems and power plant condensers.
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License
Recommended Citation
Aponte, Nhicolas; Morrow, Jordan; Riley, Gennifer; Chakraborty, Partha P.; and Derby, Melanie M. (2019). "Layered wicks enable passive transport of condensation out of cooling systems," Kansas State University Undergraduate Research Conference. https://newprairiepress.org/ksuugradresearch/2019/posters/19
Layered wicks enable passive transport of condensation out of cooling systems
Layered wicks enable passive transport of condensation out of cooling systems
Nhicolas Aponte, Jordan Morrow, Gennifer Riley, Partha Chakraborty, Melanie M. Derby
Department of Mechanical and Nuclear Engineering, Kansas State University
Cooling systems, like condensers or cooling towers of a power plant, transfer heat out of a system. The cooling process often occurs through the condensation of water, which forms a liquid film that reduces heat transfer. This problem makes cooling systems larger and more costly. One approach to this problem is drop-wise condensation in which condensed water gathers in the form of droplets which can then run off, preventing the reduction of heat transfer caused by the liquid film. For this solution to be effective in industry, a hydrophobic coating would need to last over 10 years, which is difficult to achieve. The approach studied in this work uses the capillary/surface tension forces to passively transport water, which is applicable to removing liquid films from condensers. This is investigated by using a wick, which is a structure that enables the passive transport of water. In this project, we compare wicking structures with different porosity in order to design an effective wick for industrial use. The wicks used are an array of layered spheres bridged by cylindrical columns with calculated porosity of 0.35(Wick C), 0.42(Wick B), and 0.66(Wick A). The wicks are 3-D printed onto a test plate, which allows the fabrication of complex geometries. The effectiveness of the wicks is compared using the rate-of-rise method. For this method, the wicks are lowered into a water reservoir. The interactions between the wick and the water are observed and recorded under a high speed camera. Then, the height the water rises to within the wick is compared. The wicks printed for this project outline problems we did not account for. The small pore volume of the wicks made it difficult to clean out support material after being printed. Future wicks will be designed with a greater pore volume than that of Wick C. The success of this project could improve the heat transfer in space cooling systems and power plant condensers.
