Deviation of macro-micro tubing direct transition in liquid f low comparing to the constructal transition: Experimental study and CFD simulation
Abstract
Capillary tubes have growing domain in heat transfer applications. However, complexity of micro pumps and macro-micro constructal optimum transition section impede this growth, especially for polymeric microtubes. In this study, a simplified macro-micro transition section is proposed, analyzed and tested. Three dimensional computational fluid dynamics numerical simulation was conducted to compare between the direct simplified model and the optimal constructal model. In addition, fabrication and experimental testing of the proposed design is done to study the fluid flow behavior in such design and distribution. The numerical results of pressure fields produce comparable pressure drop outcome of the direct transition design. Further, it is notable that the drop in pressure drop increases with increasing flow rate, the fact that encourages utilizing this design for higher flow rates. Moreover, the proposed direct transition design provide a well distributed flow achieved from both the numerical results and experimental measurements. The pressure drop gradient between the central and peripheral branches is very small comparing to the pressure drop. However, this gradient increases with increasing flow rate. The flow velocity of the direct transition was comparable to that of the constructal design. The flow velocity elevation in the direct design increases with increasing flow rate. The numerical simulations consolidated by the experimental results about the fairly approximate flow velocity in the micro-branches in the direct transition design. The suggested design was applied for a liquid cooling vest system successfully and can be applied for several further micro applications.
Document Type: Original article
Cited as: Abdulelah, A., Ali, L. F. Deviation of macro-micro tubing direct transition in liquid flow comparing to the constructal transition: Experimental study and CFD simulation. Capillarity, 2025, 15(2): 44-52. https://doi.org/10.46690/capi.2025.05.03
Keywords:
Microtubes, microflow, flow transition, polypropylene, constructal distribution, liquid coolingReferences
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