For three-dimensional systems, discussing the possibility of implementing quantum Hall physics has been an enduring topic. Based on Weyl semimetals, pioneering works have proposed chiral Landau levels and three-dimensional quantum Hall effect. When the degenerate band extends from nodal points to nodal lines, the magnetic field can lead to various quantum Hall phenomena, such as the three-dimensional flat Landau levels. Usually, the above exotic phenomena are explored under a uniform magnetic field with a fixed direction and magnitude. Here, we obtain a momentum-dependent pseudomagnetic field in a nodal line semimetal by designing a gradient coupling. The resulting quantum Hall surface states exhibit momentum-dependent chiral and helical transport features. These findings are experimentally confirmed in the phononic crystal platform. The novel sound transport may pave the way for acoustic devices with unconventional functions.

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• Acoustic metamaterials
• Landau levels
• Phononic crystals
• Topological materials
• Nodal-line semimetals
• Strain engineering
• Tight-binding model