The decade following the second world war heralded the publication of a collection of important papers on non-Newtonian fluid mechanics; Oldroyd’s work featured heavily in this collection. Not only did these articles establish important results, but Oldroyd’s style and methods set the scene for subsequent work in the area, exploiting mathematical analysis to formulate problems, establish results and guide further research. While Oldroyd’s name will forever be linked with the study of elastic fluids, the purpose of the present paper is to offer a modern perspective on a number of Oldroyd’s papers on viscoplastic fluids from 1947–1951 [1], [2], [3], [4], [5], [6], [7], [8]. Along the way, we sprinkle in a brief review of some of the subsequent developments stemming from Oldroyd’s advances, together with a few new results guided by his work. Following the approach of most of Oldroyd’s original papers, we focus on unidirectional flow down conduits. In an Appendix, we complement this discussion with a lubrication analysis, extending, clarifying and correcting the important original analysis of Walton and Bittleston (1991) [9]; although lubrication theory was not directly utilized by Oldroyd, the methodology aligns with his philosophy of using asymptotic and analytical approaches.

第二次世界大战后的十年预示着一系列关于非牛顿流体力学的重要论文的出版。Oldroyd 的作品在这个系列中占有重要地位。这些文章不仅建立了重要的结果，而且 Oldroyd 的风格和方法为该领域的后续工作奠定了基础，利用数学分析来制定问题、建立结果并指导进一步的研究。虽然 Oldroyd 的名字将永远与弹性流体的研究联系在一起，但本文的目的是对 Oldroyd 1947-1951 年间关于粘塑性流体的许多论文提供现代视角 [1]、[2]、[3] , [4], [5], [6], [7], [8]。在此过程中，我们简要回顾了奥德罗伊德的进步所带来的一些后续发展，以及在他的工作指导下的一些新成果。遵循 Oldroyd 的大部分原始论文的方法，我们专注于单向向下流动的管道。在附录中，我们用润滑分析补充了这一讨论，扩展、澄清和纠正了 Walton 和 Bittleston (1991) [9] 的重要原始分析；尽管 Oldroyd 没有直接使用润滑理论，但该方法与他使用渐近和分析方法的哲学相一致。