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

Turbomachinery Technical Conference & Exposition
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

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Latest update

4/2/2025 9