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arXiv · 2605.15409

A Model of a Buoyancy-Driven Heat Exchanger, with Implications for Optimal Design

Sylvie Bronsard·Charles S. Peskin
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Abstract

In this paper, we introduce a model for a buoyancy-driven, air-to-air heat exchanger. This model, derived from first principles, features a conservative boundary condition at inflow based on the compressible Bernoulli equation, and a dissipative boundary condition at outflow based on pressure continuity. We solve for the steady-state behavior numerically and asymptotically, with excellent agreement between the two, and we study the tradeoff between the efficiency and air flow predicted by the model.

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Sylvie Bronsard, Charles S. Peskin. 2026-05-14. A Model of a Buoyancy-Driven Heat Exchanger, with Implications for Optimal Design. https://arxiv.org/abs/2605.15409

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