John Henry Michell (1863-1940) published scientific papers only between 1890
and 1902, but included in his 23 papers from that short but productive period are some of the most important contributions ever made by an Australian mathematician.
In this blog I shall concentrate on the extraordinary 1898 paper "The wave resistance of a ship," Phil. Mag.(5) 45, 106-123. There are many reasons why this paper was an astounding achievement, but perhaps the most remarkable is that the resulting formula has not been improved upon to this day. In the computer age, many efforts have been made to do so, but with little success so far. The formula itself involves a triple integral of an integrand constructed from the offset data for the ship's hull, and even the task of evaluating this triple integral is not a trivial one on today's computers; another reason for admiration of Michell's own heroic hand-calculated numerical work in the 1890's. Lack of a routine algorithm for Michell's integral has inhibited its use by naval architects and ship hydrodynamic laboratories, and there has been a tendency for it to receive a bad press based on unfair comparisons, e.g. comparison of model experiments (themselves often suspect) with inaccurate computations or computations for the wrong hull, etc. The original integral is in fact quite reasonable as an engineering tool, and some new results confirming this are shown. Improvement beyond Michell is however needed in some important speed ranges, and indications are given of recent approaches that may be promising.
I had searched for this paper everywhere, and luckily I found a website (a Russian one that too!) and I dont think it is available anywhere.
The Link is here.
and 1902, but included in his 23 papers from that short but productive period are some of the most important contributions ever made by an Australian mathematician.
In this blog I shall concentrate on the extraordinary 1898 paper "The wave resistance of a ship," Phil. Mag.(5) 45, 106-123. There are many reasons why this paper was an astounding achievement, but perhaps the most remarkable is that the resulting formula has not been improved upon to this day. In the computer age, many efforts have been made to do so, but with little success so far. The formula itself involves a triple integral of an integrand constructed from the offset data for the ship's hull, and even the task of evaluating this triple integral is not a trivial one on today's computers; another reason for admiration of Michell's own heroic hand-calculated numerical work in the 1890's. Lack of a routine algorithm for Michell's integral has inhibited its use by naval architects and ship hydrodynamic laboratories, and there has been a tendency for it to receive a bad press based on unfair comparisons, e.g. comparison of model experiments (themselves often suspect) with inaccurate computations or computations for the wrong hull, etc. The original integral is in fact quite reasonable as an engineering tool, and some new results confirming this are shown. Improvement beyond Michell is however needed in some important speed ranges, and indications are given of recent approaches that may be promising.
I had searched for this paper everywhere, and luckily I found a website (a Russian one that too!) and I dont think it is available anywhere.
The Link is here.
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