DE588113C - Guide surface arrangement for open and closed channels - Google Patents

Description

Guide surface arrangement for open and closed channels The invention concerns a new application of sail-like staggered guide surfaces. Training favorable sail positions and shapes. is purely practical over the course of many centuries went on. This applies in particular to the arrangement of suitable headsails next to the main sails.

The relevant hydrodynamic processes have only recently become known recognized and gradually learned the principle of headsail on the improvement of others To apply flow processes, e.g. B. on wings in the form of the so-called. Slotted wing or on gently curved turbine and pump blades.

In the previous applications it was always about currents on slightly curved surfaces with a moderate angle of deflection.

Abrupt deflections at large angles, such as B. in the corners of Wind tunnels (cjo or i8o °) have so far either been paralleled by a large number through the entire diversion of running partition walls or through entire rows of turbine-like ones Tried to cope with guide vanes in the corner diagonals. It was quite impossible besides the diversion, the simultaneous delay, which is desirable in some cases of the flow (for the purpose of a diffuser-like conversion of speed into pressure) reach.

This is where the present invention comes in. She sets herself the task the mentioned sail-like .staggered guide surfaces even with currents with abrupt and to use strong diversions to suppress the formation of dead water and thereby to achieve effects with relatively small guide surfaces that were previously even with extensive Areas were considered impossible. It therefore extends in particular to the application and solution of this problem with irregular channels relatively sharp corners, sharp curves or even with extensions, as they are with water, air and gas pipes, open channels, weirs, raids, Connection pieces, branches, elbows, constrictions and diffusers, etc., any Kind of occurrence. -The essence of the invention is that the total channel in the area the rugged transition points through one or more sail or split wing-like staggered guide surface groups is broken down into sub-channels, but in such a way that the E. single conductive surfaces only cover a moderate fraction of their length and the downstream guide surface in each case to the center of curvature the The current is closer than the one upstream.

Then sub-channels arise, the fresh one, previously jammed and then direct the accelerated flow to the back of the following surface, so that there any approach of dead water flow is immediately blown away and the overall flow is obtained free of larger, vertebrae.

The technical progress consists in the significant shortening of the channels, in the surprising reduction of the guide surface sizes, the applicability strongest Curvatures and expansions with a considerable reduction in flow resistance, the elimination of suction or pressure pumps for suction or re-acceleration of the so-called boundary layer (the initial structure of the dead water) as well as the avoidance by machine driven large areas like the Magnus rotor.

These new effects are through experiments in the Danziger and Berliner Flow laboratories proven.

The invention is shown in the figure using the example of a go ° elbow shown schematically, at the same time as a diffuser with a very strong extension (Delay) is used. The flow entering in the direction of the arrow would be at If there are no guide walls, immediately detach them from the rugged inner wall bend and counter. the outer wall boundary m are thrown with the formation of huge eddies, the would consume most of the flow energy.

The guide surfaces are similar to those used in headsails for a long time, staggered. The wall surface l is closest to the center of curvature; the upstream lying first guide surface is farthest away. h1 overlaps the following guide surface h2 from the outside by a certain distance and thus forms a gap channel, the fresh medium on the back of h 2 and so every approach of dead water on this back washes away immediately. Guide surface h2 again overlaps the following guide surface h3, the in the present example of the sharply curved manifold or diffuser wall L am next lies. The effect of the fresh gap flow blowing through between h2 and hs removes the dead water that has accumulated on the back of h3.

Finally the fissure flow created between, h3 and 1 blows everyone Dead water attachment along Z immediately gone.

depending on the extension of the elbow or diffuser or the other Channel routing and depending on the economic requirements is sufficient, such as trials have resulted, even under certain circumstances, a single guide surface hl, which in the manner of a Foresail is staggered compared to its main patent.

The effect is of course much less than with arrangement of further guide surfaces 1z2,123. In particularly difficult cases, such as B. the Schematically shown in the figure, where a strong diffuser effect is created is to be, one will advantageously have two or three or more such guide surface groups (corresponding to i, k etc.) with the same number or a different number of individual surfaces install (see illustration).

If you think of the figure along the dash-dotted line in the In the sense of the reflection principle, mirrored upwards, one obtains the case of a T-shaped branching piece, in which the fast entering in the direction of the arrow Flow up and down at right angles with simultaneous strong deceleration branched.

If one further imagines the outer wall of the bend m completely away and on it the reflection is made along the dash-dotted horizontal line, so is obtained you have a right-angled, widened one that opens into a plane (here vertical wall) Diffuser with a particularly strong and rugged extension. In -the, two last-mentioned- Cases would be two, four, six, etc., vane groups. staggered according to the invention Type of order.

Experiments have shown that even when it is reduced in size the radius of curvature from t to zero, d. H. with sharp canal corners, with help the present invention surprising reductions in previous eddy losses can be achieved with certainty. This grants the advantage that the losses in existing duct corners or right-angled branches with sharp corners, etc. Like. Subsequent installation of these sail-like - staggered guide surfaces considerably can be reduced.

depending on the cross-section of the channels (round, oval, angular, etc.) the guide surfaces as bodies of revolution, oval or angular rings or as cylindrical Be formed surfaces.

The invention is suitable for gases, vapors or liquids any flow velocity.

In addition to the fields of application already mentioned above, the invention also advantageous for power or working machines, measuring devices (jam rims, measuring nozzles, Venturi tubes), speaking machines, civil engineering structures in rivers or canals with or without free surface, also with ventilation and boiler systems to order and distribution of the flow behind steep diversions and expansions, in short used in all cases where previously as a result of unfavorable Wall curvature and considerable centrifugal forces, strong detachments, formation of dead water and vortex losses occurred.

The thickness of the guide surfaces in the direction of flow can be variable, z. B. As with wings, turbine blades and the like.

Claims (1)

PATENT CLAIM: Guide surface arrangement for open or closed Channels with corners or other sharp curves or sharp extensions, characterized in -that the overall channel in the vicinity of the rugged transition points by one or more guide surface groups staggered like a sail or split wing is broken down into sub-channels in such a way that 'the individual conductive surfaces only on one moderate fraction. cover their length and the downstream guide surface is closer to the center of curvature of the flow than the one upstream lying.