JPS5897A - Heat transfer surface device with turbulence promoter - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat transfer surface device with a turbulence promoter for promoting heat transfer in a heat exchanger.

Conventionally, there are heat exchangers in which a heat transfer surface is simply arranged along the flow of a fluid (for example, air) as a heat medium, but such conventional ones do not cause turbulence in the fluid. Therefore, as shown in Figure 1, in order to form a flow that involves separation and re-deposition behind the turbulence gromotor, there is a problem that the heat transfer efficiency is very poor.
It has also been proposed that a flat turbidity promoter 2 is erected on a heat transfer surface 1, which is a flow channel wall surface, and is perpendicular to the flow. This has the drawback that the flow resistance in the flow direction increases significantly due to the increase in the flow resistance in the flow path, leading to an increase in the pump power required to drive the fluid. It has the disadvantage that its performance as a heat transfer surface is limited and its heat transfer efficiency is low.

The present invention aims to solve these contradictory problems by promoting turbulence in the flow of fluid as a heat medium and reducing flow resistance to achieve highly efficient heat transfer. An object of the present invention is to provide a heat transfer surface device with a turbulence promoter.

Therefore, the heat transfer surface device with a turbulence promoter of the present invention has a plate-like shape that is erected in a direction intersecting the flow of the fluid on the heat transfer surface that is disposed along the flow of the fluid as a heat medium. The plate-like turbulence promoter is characterized by having a number of through passages formed in the plate-like turbulence promoter to promote the turbulence of the fluid flow and to reduce the flow resistance. To explain an embodiment of the present invention, FIG. 2 is a schematic diagram showing the main parts of a heat transfer surface device with a turbulence promoter as a first embodiment. A plurality of flat turbulence promoters 3 are erected in a direction perpendicular to the air flow where the heat transfer surface 1 is disposed.

one! In addition, each turbulence glow motor 3 is formed with a large number of slits 3a as through passages, thereby promoting turbulence of the fluid and reducing flow resistance.

FIG. 3 is a schematic diagram showing the main parts of a heat transfer surface device with a turbulence promoter as a second embodiment of the present invention. In FIG. 3, the same reference numerals as in FIG. 2 indicate almost the same parts. There is.

In the case of the second embodiment, a plurality of flat plate-like turbulence promoters (hereinafter referred to as "perforated plate-type turbulence promoters") 4 are provided on the heat transfer surface l, each having a large number of small holes 4a as through passages. It is erected perpendicular to the air flow.

Due to the above-described configuration, compared to the conventional heat transfer surface device with a notturbulence promoter as shown in FIG. 1, the device of the present invention can reduce flow resistance and promote turbulence in airflow. Therefore, it is possible to realize a heat transfer surface device with a turbulence promoter that greatly promotes heat transfer.

Comparing the details in accordance with experimental examples, the heat transfer characteristics and flow resistance characteristics of the turbulence promoter are the same as the promoter height e, the promoter pitch p1, the promoter vacancy rate β, and the promoter height. Changes depending on the flow path representative dimension d in the direction, flow velocity U, etc. (These realistic values are
For example, e/d=0.02-0.2. p/e-s ~5
0. β=10~50%) but 1, for example, 150mX4
For an air flow of about 5+m rectangular flow path with a flow velocity u=IQm/sec, 'e=5. Qm+1 p=79+m,
Installing a perforated plate type turbulence promoter 4 with β = 23% Compared to a heat transfer surface device in which no turbulence promoter is installed upright, the heat transfer characteristics increase approximately 3 times, and the flow resistance increases approximately 8 times. .

Comparing the slit-type turbulence promoter 3 with the perforated plate type 4, the heat transfer characteristics are almost the same as those of the perforated plate type, and the actual flow resistance is approximately 12
It will be doubled.

Tokorochi, as a performance comparison of turbulence promoters, when comparing the heat transfer performance under conditions of constant pump movement,
When the flow velocity is u = 10 (m7 seconds), the one with the perforated plate type turbulence promoter 4 of the present invention has a 50 to 80% transfer rate compared to the heat transfer surface without the turbulence promoter installed at β-23. Achieve thermal promotion. Similarly, the slit-type turbulence blow motor 3 of the present invention realizes heat transfer enhancement of 20 to 50 factors when β=50%.

On the other hand, conventional flat plate type devices only achieve heat transfer enhancement of about 0 to 35%.

As mentioned above, the following table shows the ratios obtained by normalizing the average value of each data according to the experimental example with each coefficient without a turbulence promoter, in the case of a flow rate of u-10 (m7 seconds).

Here, the coefficient of friction is calculated from the flow resistance and flow velocity, and indicates the resistance of the heat transfer surface with a turbulence promoter regardless of the flow velocity, and is calculated by dividing the flow resistance by the square of the flow velocity. be.

As shown in the degree of heat transfer promotion in the previous table, those having the perforated plate type turbulence promoter 4 exhibit particularly excellent heat transfer efficiency.

Incidentally, those having the perforated plate type and slit type turbulence glow motors 4.3 are particularly effective when the flow velocity is small.

Furthermore, although the material of the plate-shaped turbulence promoter is irrelevant as far as the stirring effect is concerned, by using a material with good thermal conductivity, the fin effect is superimposed and heat transfer can be further promoted. Possible 0,
In addition to air, an appropriate gas or liquid can be used as a fluid as a heat transfer medium.In addition, this fluid may either give or take away heat from the heat transfer surface. According to the heat transfer surface device with a turbulence promoter of the invention, the following advantages and effects can be obtained.

(1) Highly efficient heat transfer can be achieved by promoting turbulence in the flow of fluid as a heat medium and reducing flow resistance.

(2) If the heat exchanger is the same size, the installation of this turbulence promoter can reduce the pump power when the heat exchange amount is constant, and increase the heat exchange amount when the pump movement is constant. (3) If the amount of heat exchanged is the same, the size of the heat exchanger can be reduced by installing this turbulence promoter.

(4) Easy to manufacture and extremely practical 0

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the main parts of a conventional heat transfer surface device with a turbulence promoter, and FIG.
FIG. 3 is a schematic diagram showing the main parts of a heat transfer surface device with a turbulence promoter as a second embodiment of the present invention; FIG. It is a diagram. 1. Heat transfer surface, 3. Slit-type turvy lens glomotor, 3a.. Slit as a through path, 4.. Perforated plate type turby lens promoter, 4a.. Small hole as a through path. Agent Patent Attorney Yoshihiko Iinuma Figure 1 Figure 2 Figure 3

Claims (3)

[Claims] (1) On a heat transfer surface disposed along the flow of a fluid as a heat medium, a plate-shaped turbeyence promoter is placed upright in a direction intersecting the flow of the fluid. A heat transfer surface device with a turbulence promoter, characterized in that the promoter is formed with a number of through passages that promote turbulence in the flow of the fluid and reduce flow resistance. (2) The heat transfer surface device with a turbulence promoter according to claim 1, wherein a large number of slits are formed in the plate-like turbulence promoter. (3) The heat transfer surface device with a turbulence promoter according to claim 1, wherein the plate-like turbulence promoter is configured as a perforated plate.