structured quad mesh with transition zone - Computational Science

I wonder which software can be used to generate the mesh like below. Anybody has an idea?

Meshing

Applied Sciences, Free Full-Text

Applied Sciences, Free Full-Text

A Level Set Model for Structured Mesh Representation of Fibrous Preforms used in Composites Manufacturing

Propagating Design Updates to Structured Analysis Meshes - ScienceDirect

Quad‐Mesh Generation and Processing: A Survey - Bommes - 2013 - Computer Graphics Forum - Wiley Online Library

A Level Set Model for Structured Mesh Representation of Fibrous Preforms used in Composites Manufacturing

Computer Graphics Group

PDF) An Open-Source Processing Pipeline for Quad-Dominant Mesh Generation for Class-Compliant Ship Structural Analysis

Applied Sciences, Free Full-Text

Computational Thermal Multi-phase Flow for Metal Additive Manufacturing