CS219029B1 - Heat Exchanger - Google Patents

Abstract

The heat exchanger according to the invention allows for an increase in the transfer surface area into the liquid medium and thus also the elimination of undesirable phenomena associated with its overheating. The essence of the invention lies in the fact that a V-shaped partition is inserted into the circular tubes of the heat exchanger's fin block, with the top edge of this partition removing heat from the most stressed areas of the tubes (see Fig. 3). The invention can be practically used in all heat exchangers in which the external medium flows in a direction perpendicular to the axis of the tubes of the fin block of the exchanger.

Description

The heat exchanger according to the invention makes it possible to increase the transfer area into the liquid medium and thus to eliminate the undesirable effects associated with its overheating.

The principle of the invention is that a V-shaped baffle is inserted into the circular tubes of the heat exchanger fin block and the apex of this baffle dissipates heat from the most stressed locations of the chests (see FIG. 3).

The invention can be practically applied in all heat exchangers in which the external medium flows in a direction perpendicular to the axis of the lamellar tubes of the exchanger block.

219 0 2 8

2190

BACKGROUND OF THE INVENTION The present invention relates to a heat exchanger particularly suitable for rapid heating water-fired water heaters for gaseous fuels.

The prior art solutions of such exchangers consist of a lamella block with one or more tubes surrounded by lamellas to increase heat transfer from the external gaseous medium to the tube within which the liquid flows.

To ensure the transfer of heat into this liquid, it is necessary to ensure a minimum inner surface of the tubes depending on the total heat output of the exchanger, which leads to considerable diameters of circular tubes in the lamella block and thereby reduce its free cross section and increase the hydraulic resistance of the entire exchanger .

On the contrary, this hydraulic resistance must be reduced as much as possible for the correct functioning of the entire exchanger, especially with regard to the perfection of combustion at the specified heat output.

The prior art solutions address these contradictory requirements, for example, by flattening the pipes, thereby achieving the desired liquid transfer area with reduced hydraulic resistance on the gaseous medium side (see Figure 1). This solution is technologically demanding and requires precise adherence to the shape of the tubes, which is fixed by the partition inside the tubes, firmly connected to its inner walls. Other solutions allow for a partial increase of the inner passage surface of the tubes by a fixed partition inside the tubes in the lamella block (see Figure 2). The disadvantage of this solution is the difficulty of fixing the baffle to the walls of the pipe at a given location and ensuring its rigidity, and also the apparent functional insufficiency with regard to the removal of heat from the most stressed point of the pipe.

The above drawbacks are overcome by the arrangement according to the invention, which is based on the insertion of a V-shaped partition into the circular tube of the heat exchanger fin block.

The effect of the solution is that the V-shaped partition, at its apex edge, dissipates heat from the most heat-stressed point of the round tube. Suitably, the joining of this apex edge with the inner wall of the pipe is made by soldering in the contact surface with respect to heat transfer.

FIG. 3 shows one embodiment of an exchanger according to the invention.

The exchanger consists of a jacket and a lamella block, which is formed by circular tubes 1 surrounded by lamellas 2. In the circular tubes 1, a V-shaped partition 3 with an apex edge oriented upstream of the gaseous medium indicated by the arrow is inserted. The gaseous medium (flue gas) flowing along the lamellas 2 transfers heat through these lamellas 2 to the circular tubes 1, from where it passes into the flowing liquid inside the tubes 1, the thermally stressed place on the tube 1 being its bottom part to which the partition 3 is soldered V, the task of which is to facilitate the dissipation of heat from this point by conduction and further transfer to the liquid.

Claims (1)

Subject A heat exchanger, particularly suitable for gas-fired instantaneous water heaters and boilers for heating, with round tubes in a lamellar block, characterized in that a V-shaped partition (3) is inserted in the tubes (1j).