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Chungnam National University > College of Engineering > Division of Aerospace · Naval Architecture & Ocean Engineering

 

 

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William Froude, FRS., LLD & his son, Robert Edmund Froude

 

 William Froude

 


William Froude was born on 28 Nov. 1810 at Dartington, Devon, England.
and passed away on 4 May 1879, at Simonstown, S.Af.

The years 1871-1872 saw the turning point in the history of ship model research. For it was at Torquay that a Victorian civil engineer called William Froude began a chain of events in his native Devon which would put Britain in the forefront of technological innovation of the time and lead in due course to the development of the world's leading ship model research establishment in a quiet backwater of Portsmouth Harbour.

Froude was born in Devon in 1810 and although a scion of literary and academic family - his brother was the distinguished historian James Anthony Froude -William went to work with Isambard Kingdom Brunel on the Great Western Railway project after Oxford University. But the sea and ships had always exercised a special fascination for him and he soon began conducting resistance experiments with small model boats in the River Dart. The first of these was carried out on scale models of the screw gunboats 'Swan' and 'Raven'. For the purpose of these experiments, Froude devised the most delicate recording apparatus fashioned out of tin and solder. This is now preserved in the Science Museum at Kensington.

Before long, Froude became fired with the determination to build his own testing tank where he could work undisturbed by both the elements and the remarks of uncomprehending spectators. Sometime during the 1860s he had acquired some ground at Torquay and built himself a house known as Chelston Cross. Froude now drew his work on models to the attention of Sir Edward Reed, Chief Constructor to the Navy, and through the latter's support was given an Admiralty grant of £2000 to cover the cost of building the model testing tank adjacent to Cheiston Cross, the day-to-day running costs of the installation and a small salary to his third son and chief assistant, Robert Edmund Froude. William Froude himself refused a salary. The loss in August 1871 of the 'Captain', a large twin screw ironclad with many design faults, caused him much distress. The ship turned turtle in the Bay of Biscay with the loss of almost the entire crew of 500. This major tragedy spurred Froude on in his determination to resolve the recurring problem of faulty design.

From time immemorial the hull design of English ships had been largely a matter of rule of thumb, allied to the accumulated experience of the master shipwright. In an earlier period, the Age of Enlightenment had produced some amateur experimenters equally concerned as William Froude to try to resolve this problem. They were as diverse as Benjamin Franklin, the Abbe' Bossut and one Colonel Mark Beaufoy who founded the Society for the Improvement of Naval Architecture in 1791. But it was the father and son partnership of the Froudes that was able to apply the knowledge gained from their empirical research at Chelston Cross. The result - the virtual elimination of design faults by the simple expedient of submitting accurate scale models to rigorous tests and in the process heralding the end of the appalling and needless loss of life at sea. The world's first model experiment using the Froude techniques was with a miniature version of HMS Greyhound in 1871. Her sea trials took place a year later in the Solent.

Chelston Cross Tank at Torquay Circa 1871

By 1885 the Torquay tank had exhausted its capacity and the lease had also run out on the land occupied by the tank. A new and much larger site capable of expansion was an urgent requirement. In 1886 Robert Edmund Froude, who had succeeded his father on the latter's death in Cape Town in 1879, supervised the transfer of the Admiralty Experiment Works to Haslar adjacent to Gunboat Yard. He chose the Haslar site in preference to three others at Chiswick, Deptford and Portsmouth Dockyards. Its relative isolation may have advanced its appeal - Haslar a hundred years ago was remote and inaccessible and in spite of modern transport and motorways, remains largely so today. Interested persons wishing to inspect the 475 feet long, 20 feet wide and 9 feet deep tank and its half million gallons of fresh water had first to negotiate Portsmouth Harbour and the vagaries of waterborne transport. 'There are no ferry or watermen's boats nor any other means of crossing to Southsea nearer than Fort Blockhouse except by special arrangements. It would not be difficult to get into or from a boat along the sea wall near the fort and from there you could, I should say, easily hire a boat from Southsea beach, but the safest and surest place to land from or embark in a boat is Haslar Jetty which is accessible all tides in any weather,' wrote Froude in a vein calculated to repulse all but the keenest visitors.

The move to Haslar coincided with the country's huge increase in the Naval shipbuilding programme. The statistics for the first two decades of Haslar model tests are impressive. By 1918 some 500 different warships models had been subjected to a rigorous programme. This tally, which includes the famous 'Dreadnought' laid down in Portsmouth Dockyard in 1906, was made up of 33 battleships, 46 cruisers, 61 destroyers, 14 submarines and 20 miscellaneous vessels.

The eminence of William Froude as an innovative engineer had been universally acknowledged in his lifetime. After his father's death, R.E. Froude received worldwide requests for advice on the building of tanks similar in every respect to the Haslar one. Italy and Russia had ship testing tanks at Spezia and St. Petersburg which were fully operational well before the end of the last century. The first commercial tank in the United Kingdom was that of Sir William Denny of Denny Bros. at Dumbarton.

The apparatus first devised by William and R.E. Froude over a century ago has changed very little in principle. A carriage runs over and along the sides of the tank on rails which have been specially aligned to take into account the curvature of the earth's surface. This mobile carriage is equipped with a dynamometer beneath which is suspended the scale model. The whole purpose of this ingenious device is to record the speed, performance and resistance of the ship's model in still water as well as its motion in waves, which can be artificially induced with a wavemaking machine. The models are moulded from paraffin wax, although nowadays fibreglass is increasingly used. Each model measures up to 20 feet in length, is 2 feet wide and of about one inch thickness. In 1885 R.E. Froude explained how the sleek shape of the hull is achieved:

Finishing off the outer surface of our paraffin model, we use flexible steel shapes. As it is important that the models should have a perfectly smooth surface, the scrapes ought to have a keen, unbroken edge. The scrapes we use are rather softer than sawplate, consequently their edges soon become dull and break away if they meet any grit'.

Early on in the life of the tank, the water became cloudy with algae growths. R.E. Froude solved this problem in a typically practical fashion. He imported a quantity of fresh water eels from Gilkicker Lake and these creatures obligingly munched their way through the weed growth until they themselves were made redundant by the introduction of chemical clearing agents. R.E. Froude finally left Haslar in 1919 having been in complete charge of the test programme since 1886. His Alverstoke home is now a popular village inn - the Old Lodge.

On the 27th May, 1879, the Lords Commissioners of the Admiralty wrote to Robert Edmund Froude on the death of his father: 'My Lords desire to convey to you and all members of your family their most sincere sympathy at the irreparable loss you have sustained - a loss which cannot be looked upon as other than a national one. They feel that Mr Froude rendered great service to the Navy and the country in making his great abilities, knowledge and powers of observation available for the improvement of the designs of ships, without reward or any other acknowledgement other than the grateful thanks of successive Boards of the Admiralty'.

It is a resounding epitaph equally applicable to his son Robert Edmund Froude, while the complex of buildings which comprise Haslar's Admiralty Research Establishment is a working memorial to them both. The maritime heritage of the Portsmouth Harbour area and the supremacy of Britain as a sea power during the late Victorian period owes a considerable debt to the work of the pioneering Froudes. Yet few people other than those with an interest in naval architecture have ever heard of them or have an inkling of the significance of their work. Their published papers are still used by today's naval architects as standard works of reference on the basic problems of ship model research. William Froude was a pioneer in the use of ship models for hydrodynamic research. This was particularly relevant at the time because the steam engine was replacing sail as the prime mover and a more scientific approach to hull and propeller design was essential to harness this power to best advantage. Quite simply, the scientifically designed hull led to a safer and more cost-effective navy.

Some of the Key Projects Conducted


 Froude number:
in hydrology and fluid mechanics, dimensionless quantity used to indicate the influence of gravity on fluid motion. It is generally expressed as F = v/(gd)-1/2, in which d is depth of flow, g is the gravitational acceleration (equal to the specific weight of the water divided by its density, in fluid mechanics), v is the celerity of a small surface (or gravity) wave, and F is the Froude number. When F is less than 1, small surface waves can move upstream; when F is greater than 1, they will be carried downstream; and when F = 1 (said to be the critical Froude number), the velocity of flow is just equal to the velocity of surface waves. The Froude number enters into formulations of the hydraulic jump (rise in water surface elevation) that occurs under certain conditions, and, together with the Reynolds number, it serves to delineate the boundary between laminar and turbulent flow conditions in open channels.