{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T12:32:52Z","timestamp":1769603572514,"version":"3.49.0"},"reference-count":43,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2024,10,1]],"date-time":"2024-10-01T00:00:00Z","timestamp":1727740800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Commission (European Regional Development Fund)","award":["11SYN_5_144"],"award-info":[{"award-number":["11SYN_5_144"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Computation"],"abstract":"<jats:p>The Direct Simulation Monte Carlo (DSMC) method, introduced by Graeme Bird over five decades ago, has become a crucial statistical particle-based technique for simulating low-density gas flows. Its widespread acceptance stems from rigorous validation against experimental data. This study focuses on four validation test cases known for their complex shock\u2013boundary and shock\u2013shock interactions: (a) a flat plate in hypersonic flow, (b) a Mach 20.2 flow over a 70-degree interplanetary probe, (c) a hypersonic flow around a flared cylinder, and (d) a hypersonic flow around a biconic. Part A of this paper covers the first two cases, while Part B will discuss the remaining cases. These scenarios have been extensively used by researchers to validate prominent parallel DSMC solvers, due to the challenging nature of the flow features involved. The validation requires meticulous selection of simulation parameters, including particle count, grid density, and time steps. This work evaluates the SPARTA (Stochastic Parallel Rarefied-gas Time-Accurate Analyzer) kernel\u2019s accuracy against these test cases, highlighting its parallel processing capability via domain decomposition and MPI communication. This method promises substantial improvements in computational efficiency and accuracy for complex hypersonic vehicle simulations.<\/jats:p>","DOI":"10.3390\/computation12100198","type":"journal-article","created":{"date-parts":[[2024,10,1]],"date-time":"2024-10-01T07:41:49Z","timestamp":1727768509000},"page":"198","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Comprehensive Evaluation of the Massively Parallel Direct Simulation Monte Carlo Kernel \u201cStochastic Parallel Rarefied-Gas Time-Accurate Analyzer\u201d in Rarefied Hypersonic Flows\u2014Part A: Fundamentals"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7502-8620","authenticated-orcid":false,"given":"Angelos","family":"Klothakis","sequence":"first","affiliation":[{"name":"Turbomachines and Fluid Dynamics Laboratory, School of Production Engineering and Management, Technical University of Crete, 73100 Chania, Greece"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0675-5880","authenticated-orcid":false,"given":"Ioannis K.","family":"Nikolos","sequence":"additional","affiliation":[{"name":"Turbomachines and Fluid Dynamics Laboratory, School of Production Engineering and Management, Technical University of Crete, 73100 Chania, Greece"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1518","DOI":"10.1063\/1.1710976","article-title":"Approach to translational equilibrium in a rigid sphere gas","volume":"6","author":"Bird","year":"1963","journal-title":"Phys. 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