We were recently witness of an experiment made at Eragny Conflans on the steam yacht Flamboyante. It was a question of testing a new vaporizer or burner for liquid fuel. The experiment was a repetition of the one that the inventor, Mr. G. Dietrich, recently performed with success in the presence of Admirals Cloue and Miot.

The Flamboyante is 58 ft. in length, 9 ft. in width, draws 5 ft. of water, and has a displacement of 10 tons. She is provided with a double vertical engine supplied by a Belleville boiler that develops 28 horse power. The screw makes 200 revolutions per minute, and gives the yacht a speed of 6½ knots.

Mr. Dietrich's vaporizer appears to be very simple, and has given so good results that we have thought it of interest to give our readers a succinct description of it. In this apparatus, the inventor has endeavored to obtain an easy regulation of the two essential elements - naphtha and steam.

Fig. 1 represents the apparatus in section. The steam enters through the tubulure, A, and finds its way around the periphery of a tuyere, D. It escapes with great velocity, carries along the petroleum that runs from two lateral tubulures, B (Fig. 2), and throws it in a fine spray into the fireplace, through the nozzle, C (Fig. 1), which is flattened into the shape of a fan opened out horizontally. The mixture at once ignites in contact with the hot gases, and gives a beautiful, long, clear flame. The air necessary for the combustion is sucked through the interior of the nozzle, H, which is in front of the tuyere. It will be seen that the current of steam can be regulated by moving the tuyere, D, from or toward the eduction orifice. This is effected through a maneuver of the hand wheel, F. In the second place, the flow of the petroleum is made regular by revolving the hand wheel, G, which gives the piston, O, a to and fro motion in the tuyere, D.

FIG. 1   THE DIETRICH PETROLEUM BURNER.
FIG. 1 - THE DIETRICH PETROLEUM BURNER.

The regulation may be performed with the greatest ease. It is possible to instantly vary, together or separately, the steam and the petroleum. Under such circumstances, choking is not to be feared at the petroleum orifice, where, according to experiment, the thickness of the substance to be vaporized should not be less than 0.04 of an inch.

The petroleum might evidently be made to enter at A and the steam at B; but one of the conclusions of the experiments cited is that the performance is better when the jet of steam surrounds the petroleum. It will be understood, in fact, that by this means not a particle of the liquid can escape vaporization and, consequently, combustion. Moreover, as the jet of petroleum is completely surrounded by steam its flow can be increased within the widest limits, and this, in certain cases, may prevent an obstruction without much diminishing the useful effect of the burner.

The apparatus is easily and rapidly taken apart. It it is only necessary to remove the nozzle, C, in order to partially clean it. It would even seem that the cleaning might be done automatically by occasionally reversing the flow of the steam and petroleum. However efficacious such a method might prove, the apparatus as we have described it can be very easily applied to any generator. Fig. 2 represents it as applied to the front of a furnace provided with two doors. A metallic box, with two compartments, is placed on one side of the furnace, and is provided with two stuffing boxes that are capable of revolving around the steam and petroleum pipes. The latter thus form the pivots of the hinge that allows of the play of the vaporizers and piping.

FIG. 2   THE BURNER APPLIED TO THE FURNACE OF A BOILER.
FIG. 2 - THE BURNER APPLIED TO THE FURNACE OF A BOILER.

It was in this way that Mr. Dietrich arranged his apparatus in an experiment made upon a stationary boiler belonging to a Mr. Corpet. The experiment was satisfactory and led to the adoption of the arrangement shown in Fig. 3. The fire bridge is constructed of refractory bricks, and the majority of the grate bars are filled in with brick. The few free bars permit of the firing of the boiler and of access of air to the interior of the fire box. Under such circumstances, the combustion is very regular, the furnace does not roar, and the smoke-consuming qualities are perfect.

FIG. 3   APPLICATION OF THE BURNER TO A RETURN FLAME BOILER.
FIG. 3 - APPLICATION OF THE BURNER TO A RETURN FLAME BOILER.

In the experiment on the Flamboyante, the boiler was provided with but one apparatus, and the grate remained covered with a layer of ignited coal that had been used for firing up in order to obtain the necessary pressure of steam to set the vaporizer in operation. This ignited coal appeared to very advantageously replace the refractory bricks, the role of which it exactly fulfilled. It has been found well, moreover, to break the flames by a few piles of bricks in the furnace, in order to obtain as intimate a mixture as possible of the inflammable gases.

It is to be remarked that firing up in order to obtain the necessary steam at first is a drawback that might be surmounted by using at the beginning of the operation a very small auxiliary boiler. The main furnace would then be fired by means of say a wad of cotton. But, in current practice, if a grate and fire be retained, the firing will perhaps be simpler.

With but one apparatus, the pressure in the Flamboyante's boiler rose in a few minutes from 6 to 25 pounds, and about a quarter of an hour after leaving the wharf the apparatus had been so regulated that there was no sign of smoke. This property of the Dietrich burner proceeds naturally from the use of a jet of steam to carry along the petroleum and air necessary for combustion. It is, in fact, an Orvis smoke consumer transformed, and applied in a special way.

It must be added that the regulating requires a certain amount of practice and even a certain amount of time at every change in the boat's running. So it is well to use two, and even three, apparatus, of a size adapted to that of the boiler. The regulation of the furnace temperature is then effected by extinguishing one or two, or even three, of the apparatus, according as it is desired to slow up more or less or to come to a standstill.

The oil used by Mr. De Dosme on his yacht comes from Comaille, near Antun. The price of it is quite low, and, seeing the feeble consumption (from 33 to 45 lb. for the yacht's boiler), it competes advantageously with the coal that Mr. De Dosme was formerly obliged to use. - La Nature.

[Continued from SUPPLEMENT, No. 622, page 9935.]