Testing Of A Cooling Fan For Wing-Bay Electro-Mechanical Actuators

The scope of the work is to develop a cooling system which uses wing-bay air to cool the ElectroMechanical Actuators (EMA). The wing-bay is enclosed. The system will operate between 20% and 100% of atmospheric pressure. Using high speed fans as a means of cooling the EMAs it is important to understand the characteristics of the fan. The study also closely observed the results obtained experimentally with that of the fan scaling analysis. The fan laws can be derived from dimensionless analysis of volumetric flow rate, static pressure, and power equations. Considering the current experimental data, the fan scaling laws can be used to verify the proper nature of the fan curves when using a certain measurement at the baseline. In this study, the results have been verified for various rotational speeds and ambient pressure conditions. Consequently, there are two fans that have been tested within the loop. The first fan is a 2 bladed fan whereas the other fan has a 12 bladed propeller. The fan performance curves will determine the cooling capacities of each and provide a means to compare geometrically different fans

Experimental study for enhancing condensation on large-scale surface using hybrid hydrophilic-hydrophobic patterns

Improving condensation on large-scale surfaces promotes a wide range of manufacturing fields. To take advantage of both dropwise and filmwise condensation properties, both hydrophobic and hydrophilic surfaces can be developed on one hybrid surface. In this paper, experimental studies were performed on vapor condensation over a flat vertical plate. Three different surfaces were utilized: hydrophilic (aluminum), hydrophobic (coated), and hybrid surfaces with distinctive hydrophilic and hydrophobic patterns. The effect of the volume flow rate of the cooling water was investigated from 5 L/min to 15 L/min. For the hybrid surfaces, three types of patterns were studied: separated holes of hydrophilic patterns (the island) with two different diameters, arrow pattern, and tree pattern. According to the results, the heat transfer rate varied as the surface conditions changed. For the aluminum surface that resulted in filmwise condensation mode, the observed heat transfer rate was less than that of the coated surface, which showed a combination of filmwise and dropwise condensation modes. For the hybrid surfaces, the observed heat transfer rate was higher than that of the coated surface. From all the surfaces in this study, the highest heat transfer rate was for the 2.0 mm diameter island pattern