Numerical model development and experimental evaluation of a heat exchanger manufactured by additive manufacturing operating with supercritical CO2

• Grant number: 22/15785-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2023
• End date: March 31, 2025
• Field of knowledge: Engineering - Mechanical Engineering - Thermal Engineering
• Principal Investigator: Gherhardt Ribatski
• Grantee: Ana Elisa Leonel Ferreira
• Host Institution: Escola de Engenharia de São Carlos (EESC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated scholarship(s): 24/05743-6 - Evaluation of bubble growth, sliding and detachment in shear flows, BE.EP.IC

Abstract

This study is included in a broad research project under development at the Thermal Hydraulics Laboratory at the University of Wisconsin-Madison focused on the increase of the overall efficiency of aircrafts by recovering high-temperature waste heat from the turbines. In this context, the present research involves the application of supercritical fluids as a heat transport medium. The present proposal consists on the theoretical and experimental evaluation of the performance of a heat exchanger operating in a Brayton Cycle with supercritical carbon dioxide operating as hot and cold fluids. This heat exchanger is composed of microchannels and produced by Haynes 282 additive manufacturing. A unidimensional model consisting of discrete elements will be developed using MatLab as a computational tool and the properties of CO2 evaluated from Refprop. Prediction methods for pressure drop and local heat transfer coefficient available in the literature will be incorporated into the numerical model. The model will provide estimate of the total heat transfer coefficient along the heat exchanger, the associated pressure drop and parameters employed on the evaluation and design of heat exchangers such as effectiveness, conductance, volumetric power density and factor of compactness. Subsequently, the numerical model will be validated based on a series of experiments for a similar heat exchanger performed by the student associated to the proposal in an experimental apparatus available at the Thermal Hydraulics Laboratory of the University of Wisconsin-Madison. A Scholarship Abroad (BEPE) associated to the Scientific Initiation grant in Brazil will be requested to suport the student abroad during the experimental period.