CS200842B1 - Apparatus for raising heat transfer in tubes of heat exchanging plants - Google Patents

Description

BACKGROUND OF THE INVENTION The present invention relates to a device for increasing heat transfer in tubes of heat exchange apparatuses, particularly suitable for media with a high temperature dependence of viscosity.

In the prior art heat-exchanging apparatuses, to increase the transferred heat output, in particular by means of a medium with increased viscosity-temperature dependence, use a heat exchanger. both types of installation.

The first type of built-in is built-in that increases the heat-exchanging surface, mostly internal ribs of various arrangement. By increasing the heat transfer surface while maintaining the heat transfer coefficient and increasing the transferred heat output.

□ different type of installation jet - swirls, where the heat transfer coefficient and thus 1 transferred heat output are increased by the whirling of the bar. Oako swirl aa uses a lever coiled into a helix of varying pitch or sheared, transversely placed plates or a set of balls positioned immovably in the tube. In addition, wire brushes or wire lint or chips which are not sealed into the pipe can also be used as wavers. The effect of these installations increases the turbulence of the flowing medium, thereby increasing the heat transfer coefficient and the transferred heat output. A combination of ribbed and swirlers is also used. The disadvantages of ribbed internals are their costly manufacture and complex technology. Installation in pipes so that the best possible contact between the ribs and the pipe wall is achieved.

As the length increases, it becomes more difficult to install ribbed internals into pipes. The disadvantage of the swirls formed by the twisted band is the difficulty of producing the lever and the uniform climb

0 8 4 · 2

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The helix and, in particular, maintaining this uniformity when installing the strip in the pipe. The disadvantage of the swirls formed by brushes or chips is the high weight of the installation and, in particular, the substantial incremental pressure loss of the flowing medium compared to the other installations, and the need for a substantial increase in the power consumption of the pumps conveying the medium into the tubes.

The most preferred type and installation is a vortex consisting of spheres immovably placed in the tubo. The advantage of this type of installation is that the beads can be made of non-metallic material that is resistant only to the physical and thermal properties of the medium, has made it easy to install the beads into the tube by pouring and a favorable heat transfer coefficient. Especially due to the low pressure loss.

Said advantages of the bead formed by the immovable balls located in the tube further increase the heat transfer device in the tubes of the heat transfer apparatuses of the invention, which is a rigid body, preferably balls, located in the heat tube which is connected at both ends to the chambers. It is characterized by the fact that the solids fill 0,990 to 0.99Θ of the length of the heat exchanger tube and consist of balls whose diameter corresponds to 0.55 to 0.80 of the inner diameter of the heat exchanger tube.

As the medium flows, the solid particles, spheres are distributed uniformly over the long distance of the tube. Due to the kinetic energy of the flowing medium and the marked change in its microcosm with temperature change, the beads made of a relatively lightweight material are vibrated. By vibrating the balls, there was a further significant increase in the heat transfer coefficient and the damping of the transferred heat output.

An exemplary embodiment of an apparatus for increasing heat transfer in tubular heat exchange apparatuses of the present invention is shown in the accompanying drawing, wherein FIG. Fig. 2 is a cross-sectional view of the heat exchange tube of Fig. 1 as seen in Fig. 1.

In the apparatus shown in FIG. 1, the topsheet 1 is filled with balls 3 and provided with gratings 4 at the points of entry into the chambers 2 from the inside. The diameter of the spheres 3 and 0.55 to 0.80 of the inner diameter O of the heat exchange tube. This avoids placing two balls side by side. After pouring the beads 3 into the tube 3, 0.004 to 0.008 of the distance L of the heat exchange tube 6 is left free, without the beads 3. In FIG. .

Compared to installations in which the increase in the transferred heat output is achieved by increasing the heat transfer surface, such as the internal fins, and the device according to the invention achieves an increase in heat transfer by 15 to 30%,

In comparison with β-waves in the form of a set of spheres immovably placed in the tube, an increase in heat transfer of 40% is achieved in the device according to the invention, as shown by the measurement results. All the advantages of this arrangement are preserved, i.e. the tenderness of using balls of non-metallic material, e.g.

200 842 only the physical - ohemical and thermal properties of the flowing medium, easy installation into the pipe - by pouring, etc.

Claims (2)

Apparatus for increasing heat transfer in tubes of taploemane apparatus consisting of: a system of solid particles, preferably spheres, housed in a heat exchanger tube which is connected at both ends to the chambers and provided with lattices in the chambers transition to the chambers, characterized in that the solid particles (3) fill 0,990 to 0,998 length (L) 1) and consisting of spheres whose diameter corresponds to 0.55 to 0.80 of the inner diameter of the heat exchanger tube (1). Device according to claim 1, characterized in that the solid particles (3) fill from 0.992 to 0.996 of the length (L) of the heat exchange tube (1).