1844.] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



325 



Many endeavours havp been made by men of science to improve 

 tbis stute of affairs, and latterly, a great deal of attention has been 

 directed to tbe turbine. Under tbe general name of turbine are in- 

 cluded water wheels i'ormed on very dift'erent princi|)les, and which 

 have nothing in common but the property of all turning on vertical 

 shafts. M. Burdini, Mining Engineer, first imagined and made known, 

 under the name of tuibine, machines which received the water in the 

 upper part of a vertical cylinder or drum, and eject it from tin' lower 

 part ; the water is guided by vertical channels in tlie rim of the drum, 

 which must have a lieight equal to half the entire height of the avail- 

 able fall of water. ' 



M. Fourneyron has occupied himself a good deal with turbinec, iind 

 the model of one erected at the Mills of St. Maur, near Paris, was ex- 

 hibited. In Fourneyron's turbine the drum is always made rather 

 narrow. The v\aler glances obliquely in horizontal jets on the whole 

 contour of an internal vertical cylinder, and penetrates in everv direc- 

 tion the compartments of the wheel, which in turning just touches this 

 external cylinder, and follows by passing the curved buckets or cham- 

 bers inclosed in the horizontal bases, and escapes horizontally from 

 the external rim of the drum. 



The construction of turbines suggests the most complicated pro- 

 blems of hydraulics, and theory has not yet afforded the means of solv- 

 ing them « /jr/or/, practice alone gives any solution at present. The 

 greatest difficulties in the turbine are in the details of execution. The 

 water to produce the maximum effect must enter without shock, and 

 leave without velocity. M. Fourneyron has constructed several tur- 

 bines, but he has not made known the proportions which lie gives to 

 them. From the experiments of M. Savcery, it was established that 

 even with falls so slight as one foot, up to 3, 10, 15 and 25 feet, the 

 disposable work transmitted by the turbine reached from 7 to S-tenths 

 of the motive power. 



Turbines, of all hydraulic wheels, are those which under the smallest 

 volume of water utilize the greatest quantity. The water which pro- 

 pels them does not press on the axis. The high and variable speed 

 which can be given to them, without sacrifice of power, allows the 

 abandonment, in many factories, of a quantity of mill-work and heavy 

 spindles, for the purpose of accelerating the movements. Another 

 property of the turbine, and perhaps the most important, is that of 

 working when it is completely immerged in the stream a fraction of 

 the absolute power at least as great as when working above. This 

 allows, at all times, the whole fall of a stream to be turned to account. 

 From this property, M. Arago has conceived the plan of establishing 

 a complete system of turbines on the Seine, in order to provide for the 

 supply of water to Paris. 



M. Fontaine Baron lias sent to the Exposition a turbine of IS h. p., 

 which much resembles th;)t of M. Fourneyron, though differing in some 

 details, and particularly in the direction given to the chambers or 

 buckets. M. Fontaine, who lives at Chartres, has already constructed 

 thirty or forty in that part of France, where the corn trade is a prin- 

 cipal one. M. Taffe has frequently applied a register to M. Fontaine's 

 machine, and certified the useful effect to be 79 per cent. 



Kcechlin's Turbine. 



M. A. Koechlin also exhibited a turbine patented by him, the con- 

 struction of which consists of two hollow conical centres surrounded 

 with helical blades a and d, the upper one d, is fixed and serves as a 

 guide for the flow of water on to the blades of the lower one a, called 

 the turbine ; by the force of the current, the water causes tbe turbine 

 to revolve, and wit it the vertical shaft on which it is keyed and the 

 bevelled wheels above. Both the fixed and moveables turbine are 

 placed within the month of a tube, the orifice of which is contracted in 

 such a manner as to allow the proper quantity of water to pass through, 

 that is due to the velocity arising from the difierence of two levels of 

 water above and below the turbine. The advantages of Kcechlin's 

 turbine are, that the turbine may be placed at any point taken in the 

 height of the fall according to circumstances, the inferior column may 

 be prolonged at will. Also, the action of the water acts simultaneously 

 by the pressure of the inferior column, and from this combination the 

 inventor has called his machine the double-acting turbine. This system 

 of construction offers advantages which will be appreciated by those 

 who are awsre of the great expense of millwork for foundations. 



It is sufficient for these turbines to place below the surface of the 

 lower level the conduit for conveying the descending current, with a re- 

 gulating sluice at the end, and to fix the stay block which receives the 

 arbour or point of the shaft in the interior of the tube at the most con- 

 venient height, taken between the surfaces of the two levels. In this 

 manner, it is always easy instantaneously to run the wheel dry, and 

 so keep it underhand. The turbine is also provided with a sluice 

 for its supply, and when it is required to be put in motion it is opened 

 to give passage to the water, and the receiver is first allowed to be 



filled completely up to above the turbine, when the discharge sluice is 

 opened and the water allowed to flow out in quantity and relation to 

 that of supply, so that the column within the receiver is always kept 

 to one level. 



Reference to the Engravings, Plate XIII. 



Fig. 1, vertical section of the turbine through A B of fig. 2. 



Fig. 2, transverse elevation taken through C D of fig. 1. 



Fig. 3, horizontal section through E F of fig. 1. 



The same letters are used for the same parts in each of the three 

 figures. 



a, water wheel called the turbine; b, shaft of the turbine ; c, block 

 or step supporting the axis b ; d, guide or Ji.ved turbine, supplied with 

 helical curves which serve to give to the fluid vein the desired direc- 

 tion; f, case of the turbine; /, upper channel ; g, lower channel; h, 

 sluice of the canal /, to regulate the flow to the turbin.-; i, sluice of 

 the canal g ; k, float; Z, upper collar of the shaft 6; >«, support of the 

 collar l\ II, bevel wheels and shaft of transmission, supported by an- 

 other collar, which like the former is secured to the support, m. 



Fig. 1 represents the water of the upper channel f, in communica- 

 tion with the lower channel g, passing through the guide d, the tur- 

 bine a, and the case e, which may properly be called the channel of 

 junction. It is by passing through the turbine a, that the water im- 

 presses on it a rotary movement in the direction indicated by the 

 arrow a', fig. 3, a direction which would be inverse if the guides as 

 well as the vanes of the turbine were inclined in the opposite direction 



Passot's Turbink. 



M. Passot also exhibited one of his turbines fsee figs. 4, 5 and 6, 

 Plate XIII.), the construction of which is founded upon using reactino- 

 wheels, and produced by the effect of centrifugal force. They are 

 composed of cylindrical vessels fixed to vertical arbours, and supplied 

 at the circumference with orifices intended for the introduction or 

 ejection of the water. The modification vvliich M. Passot has intro- 

 duced into the old reacting wheels, and which he claims as his inven- 

 tion, consists of having suppressed or got rid of the internal partitions 

 and reduced the old wheels to their only true essential elements — a 

 motive cylinder to contain the motive fluid, with surfaces to receive 

 its action, and corresponding orifices for discharge. The surfaces 

 and the orifices are exactly included between two concentric circum- 

 ferences, that is to say, that be carefully retrenches all other surface 

 or projection capable of impressing the water with the angular move- 

 ment of the wheel before having reached the parts destined to receive 

 its action, as well as the orifices of discharge. "I form the new 

 wheel." says M. Passot, "simply by placing either in the interior or 

 exterior of a cylindrical drum, according as I want the pressure of 

 the fluid to be exerted on the interior or exterior, curved vanes in the 

 arc of a circle, such as a, h, c, d, figs. 1 and 2, then I make orifices of 

 discharge, by removing from these vanes and from the cylinder the 

 part in form of a wedge a, b, d, and the motion is effected by viitue of 

 the pressure on the faces c d, c' d', c" d". 



Fig. 1. 





" While the machine is very simple, its properties are very re- 

 markable. When the wheel turns without load or work under a given 

 difference of level or fall, its vanes take exactly the theoretical velo- 

 city due to the fall. It is no longer the same when in any manner the 

 form of the new wheel is altered so as to approach those formerly 

 known ; all partitions, projections,and asperities which are either within 

 or without two concentric circumferences, considerably diminish the 

 theoretic velocity of rotation due to the fall, on account of the con- 

 tinual shock of these bodies in motion against the water in repose. 

 Then it is not surprising if the useful effect of reacting wheels when 

 experimented upon has never risen above 50 per cent., that is to say, 

 about the rate of breast wheels of the usual varieties. 



"The expenditure of water in fig. 2, with the internal action is 

 sensibly independent of the greater or less reaction of the wheel. In 

 fig. 1, with esteraal action this cannot take place on account of the 



