Waste heat recovery unit

Heat transfer coefficient

Engineering

Heat transfer

Waste heat

Materials science

Brayton cycle

Heat exchanger

Plate heat exchanger

Supercritical fluid

Thermal hydraulics

Mechanical engineering

Thermodynamics

Physics

Nuclear engineering

Organic chemistry

Thermal efficiency

Combustion

Environmental science

Chemistry

Plate fin heat exchanger

Applied Energy

The supercritical carbon dioxide (SCO2) Brayton cycle is the most promising system in ship exhaust gas waste heat recovery. A printed circuit heat exchanger (PCHE) is used in the SCO2 Brayton cycle due to its high efficiency and compactness. To study the thermal–hydraulic characteristics of a PCHE as a precooler in a marine SCO2 Brayton cycle power generation system, a PCHE test platform was built, and substantial test results were obtained. These results suggest that the traditional heat transfer correlation does not accurately predict the heat transfer characteristics of SCO2. Subsequently, a simulation model established by a computational fluid dynamics (CFD) method is verified according to the experimental results, simulation calculations are carried out based on the design condition of the precooler in the marine Brayton cycle power generation system, and the axial, radial and global hydraulic and thermal characteristics of PCHE are analyzed. Finally, according to the CFD results, a new heat transfer correlation of SCO2 is obtained, thus providing a theoretical foundation for the design of precoolers in actual marine Brayton cycle power generation systems.

Thermal-hydraulic performance analysis of printed circuit heat exchanger precooler in the Brayton cycle for supercritical CO2 waste heat recovery