Perfecting refrigerator freezers through magnetic resonance velocimetry

Magnetic resonance velocimetry (MRV) is a flow visualization technique extending to opaque and complex internal structures. It measures both mean velocity field and turbulent kinetic energy (TKE), two factors important for improving energy efficiency and reducing flow-induced noise. Compared to other methods, which either demand extensive resources or rely on optical techniques, MRV is better suited for industrial settings. This includes appliance manufacturing, which requires both energy efficiency and low noise.

Noting the rising demands for advanced household appliances, Dong et al. used MRV to analyze the complex internal flow of freezer components.

“Our application of MRV allowed us to visualize three-dimensional (3-D), three-component velocity fields and quantify turbulent kinetic energy, enabling precise structural modifications within a refrigerator freezer model,” said author Simon Song. “This led to substantial improvements, including a 15% increase in effective flow rate through the evaporator’s finned area and reduced turbulence.”

After 3D-printing a standard freezer model, the authors examined the mean velocity and TKE fields across five strategic planes of the component. Their results linked flow distributions to the locations of inlets and outlets, and pinpointed areas with elevated TKE and flow-induced noise. They proposed a revised model with structural modifications that even out flow distributions, translating to smoother operations.

Building on this usage of MRV, the authors plan to further explore its practical applications.

“We aim to combine MRV with flow-induced noise measurements to confirm that TKE reduction correlates with lower noise levels,” said Song.

Source: “Enhancing flow uniformity and reducing turbulent kinetic energy in refrigerator freezers through magnetic resonance velocimetry-based structural modifications,” by Hangfei Dong, Chaehyuk Im, Chiho Kang, and Simon Song, Physics of Fluids (2024). The article can be accessed at https://doi.org/10.1063/5.0238809 .