## 3 Materials and Methods
### Innovative Geometrical Configuration and Design Parameters  
Two electrodes with a high aspect-ratio create an electric corona discharge when an elevated DC electric field is applied between them. Considering a positive polarity, the innovative configuration studied is based on as a micrometric wire as emitter and a collector electrode with a convergent shape (plane-fin combination) [28]. In addition, with the aim of separate the inlet and outlet of the fluid, dielectric barriers have been integrated into the sides of the wire, which have a determinedthickness t and height H. A sketch of the experimentally studied TRAID configuration is shown in Figure 2A. Several geometric parameters are analyzed in this document, which are summarized in Table 1. The materials selection as emission electrode are tungsten and stainless steel with diameters from 25 to 100 \(\upmu\)m, correspondingly. The device studied consists of two pieces which are assembled: on the one hand, a dielectric piece that allows separation between electrodes according to the gap studied and on the other hand, the ground electrode accomplishes a pure machined aluminum bulk with convergent shape. The inter-electrode separation is examined by changeable distances of 500 \(\upmu\)m in a range from 1 to 3 mm.  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Parameter** & **Value** \\ \hline Applied voltage, _Ve_ & 0 to 6 kV, DC \\ \hline Corona wire diameter, \(d_{c}\) & 25, 50, 100 \(\upmu\)m \\ \hline Electrode gap, \(g\) & 1, 1.5, 2, 2.5, 3 \\ \hline Internal channel width, C & 8 mm \\ \hline Fins/Channel height, \(H\) & 6 mm \\ \hline Thickness of dielectric barriers, \(t\) & 1 mm \\ \hline Dielectric barrier separation, \(s\) & 2 mm \\ \hline Dielectric barrier height, \(b\) & 3 mm \\ \hline Channel length, \(w\) (=corona wire and grounded \\ collector length) & 50 mm \\ \hline Total width of the prototype device, \(a\) & 28 mm \\ \hline Material & Wolfram, 7076 Aluminum alloy \\ \hline \hline \end{tabular}
\end{table}
Table 1: Geometric parameters used in this validation study.  
Figure 2: **(A) Electrode TRAID arrangement with wire-to-plane-fins and dielectric barriers; (B) Schematic CAD design of the proposed corona device for enhancement thermal dissipation; (C) Manufacturing by 3-D printing of the dielectric piece and mechanized aluminum ground electrode.**  
Considering the described TRAID configuration, a rapid prototype device with corona effect is designed and manufactured to improve thermal dissipation for application in electronic components. There are numerous computer-aided design and engineering (CAD) programs that help innovation and complex product development. In this study, the design is carried out using NX-8.5 which is commercial software by Siemens PLM Solutions. Figure 2B shows the schematic CAD design of the prototype used for the tests carried out in this investigation where the pattern is repeated three times across. Therefore, the manufacturing of the dielectric structure that will position the wire at a certain electrode separation is by methods of three-dimensional (3D) printing [36]. Additive-layer manufacturing is a versatile and economical set of techniques that allow to obtain pieces with sophisticated geometries in short periods of time and to affordably optimize the final design of the device, reducing its dimensions and weight. In our case, the 3D printing technology (BQ Hephestos 2) used is fused deposition modeling (FDM) in which we use acrylonitrile butadiene styrene (ABS) as the printing material (3D Smart Materials). Finally, we reach a prototype for testing whose crucial dimensions include a channel depth of ground electrode and wire length of 50 mm, device width and height are 28 and 8 mm respectively (volume = 11.2 cm\({}^{3}\)), and a total weight of 17 gr.