A boundary-value problem for a three-dimensional Helmholtz equation in a domain shaped as an unbounded rectangular wedge is under consideration. An exact solution to this boundary-value problem is constructed in the form of a packed block element necessary for investigating more complex and even mixed problems for block structures. Packed blocks are joined into a block structure by creating quotient topologies of the topological spaces of blocks, and the equivalence relations are interblock boundary conditions.

中文翻译：

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研究占据三维矩形楔形区域的介质的声学和流体动力学特性的问题

正在考虑形状为无界矩形楔形域中的三维亥姆霍兹方程的边值问题。这个边值问题的精确解是以打包块元素的形式构造的，这对于研究块结构的更复杂甚至混合问题是必要的。通过创建块的拓扑空间的商拓扑，将打包块连接成块结构，等价关系是块间边界条件。