Aero-thermo analysis of a waste heat recovery heat exchanger
Paper in proceeding, 2025
This study investigates the aerothermal performance and flow dynamics of a heat recovery heat exchanger for the WET cycle concept. A combined experimental and numerical approach is used to assess how flow turning influences heat transfer and pressure losses. The heat recovery unit comprises a radially distributed tube bank, with a length in excess of two meters, downstream of the turbine exhaust. The tested 30 degree sector, consists of 860 tubes. The selected heat recovery design, with the exhaust gases radially turned 90 degrees and flowing through the tubes, results in a highly non-uniform flow posing significant challenges for accurate performance assessment.
The experimental evaluation was conducted at Chalmers University using a 1:1 scale model operating under engine representative conditions. Numerical RANS simulations were performed at GKN Aerospace Sweden using ANSYS Fluent on a computational domain of 65 million cells, with a detailed in-tube model for heat transfer evaluation.
The overall aerothermal performance shows good agreement between experimental and numerical results; however, at a detailed level, notable discrepancies are identified. The effect of baffle spacing on flow stability and pressure loss distribution is discussed in detail. This study highlights the potential of the combination of relatively simple experimental configurations in combination with detailed numerical simulations provide insights into non-standard HEX configurations.
HRSG
WET
HEX
SWITCH
waste heat recovery
Author
Isak Jonsson
Chalmers, Mechanics and Maritime Sciences (M2), Fluid Dynamics
Jonas Bredberg
GKN Aerospace Sweden
Valentin Vikhorev
Chalmers, Mechanics and Maritime Sciences (M2), Fluid Dynamics
Yasser Alrifrai
GKN Aerospace Sweden
Jonathan Bergh
GKN Aerospace Sweden
Proceedings of the ASME Turbo Expo
Tennesse, Memphis, USA,
SWITCH - Sustainable Water-Injecting Turbofan Comprising Hybrid-electrics
European Commission (EC) (101102006SWITCH), 2023-01-01 -- 2025-12-31.
Subject Categories (SSIF 2025)
Fluid Mechanics
Mechanical Engineering
Applied Mechanics
Infrastructure
Chalmers Laboratory of Fluids and Thermal Sciences