Screening analyses and numerical simulation applied to flat-plate solar air heaters with rectangular-winglet vortex generators under laminar flow conditions.

• Grant number: 18/04639-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2018
• End date: May 31, 2019
• Field of knowledge: Engineering - Mechanical Engineering - Thermal Engineering
• Principal Investigator: Daniel Jonas Dezan
• Grantee: Rafael Módolo Dias Duarte
• Host Institution: Centro de Engenharia, Modelagem e Ciências Sociais Aplicadas (CECS). Universidade Federal do ABC (UFABC). Santo André , SP, Brazil

Abstract

The thermal-hydraulic performance of solar collectors depends on the ability of the working fluid to remove the heat stored on those devices. Basically, the benefits of heat transfer enhancement by using special surface geometries are due to an increase of the convective heat transfer coefficient or/and surface area. The use of modified surfaces reduces the thermal resistance and thus provides an increase of the convective heat transfer coefficient. However, the heat transfer enhancement is always associated with pressure drop increasing. This research deals with the numerical investigation of the thermal-hydraulic performance of flat-plate solar air heaters with longitudinal vortices generators (LVGs), such as rectangular winglet vortex generators. The LVGs enhance the heat transfer through secondary vortices generation with low pressure losses. It is well known that there are a lot of parameters which can affect the thermal-hydraulic performance of LVGs. Thus, it is evident that the amount of the design of experiments to maximize the thermal-hydraulic performance of this type of surface can be enormous. Based on this, it has used a non-parametric method for screening the input parameters (via Smoothing Spline ANOVA method) to evaluate the contribution of the input variables and their interactions on the thermal-hydraulic performance of the proposed solar collector.