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We propose a height-field-based real-time simulation method for sand and water mixtures. Inspired by the shallow-water assumption, our approach extends the governing equations to handle two-phase flows of sand and water using height fields. Our depth-integrated governing equations can model the elastoplastic behavior of sand, as well as sand-water-mixing phenomena such as friction, diffusion, saturation, and momentum exchange. We further propose an operator-splitting time integrator that is both GPU-friendly and stable under moderate time step sizes. We have evaluated our method on a set of benchmark scenarios involving large bodies of heterogeneous materials, where our GPU-based algorithm runs at real-time frame rates. Our method achieves a desirable trade-off between fidelity and performance, bringing an unprecedentedly immersive experience for real-time applications. 

Abstract Relaxor ferroelectric polymers exhibiting a giant electrocaloric effect (ECE) can potentially be used to create next‐generation solid‐state coolers. Under an electric field, poly(vinylidene fluoride‐trifluoroethylene‐chlorofluoroethylene) terpolymer goes through a large dipolar entropy change producing a high adiabatic temperature change (ΔT_ECE). This work resolves the molecular origins of the large entropy change behind the electric field‐induced dipole switching. A Fourier transform infrared spectroscopy equipped with a high voltage source is used to operandoly observe the characteristic molecular vibrational modes. A short‐range trans (T) conformation of the CF₂‐CH₂dyads interrupted by a gauche (G) conformation, e.g., TTTG in the terpolymer chain, undergoes a dynamic transformation that leads to a corresponding ΔT_ECEwhenever an electric field is applied. The molecular dynamics simulation also proves that the energy barrier that the transformation from TTTGs into a long T sequence overcomes is smaller than that for all other conformations. A mixed solvent system is used to obtain T3G‐enriched terpolymer films exhibiting a 4.02 K ΔT_ECEat 60 MV m⁻¹and these films are employed to manufacture a 2‐layer‐cascaded cooling device that achieves a 6.7 K temperature lift, the highest reported value for a 2‐layer cascaded device made of fluoropolymers.