JPS6315520B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a heat exchanger tube for a heat exchanger widely used in the field of air conditioning equipment, in which an impeller for promoting heat transfer is installed in the tube for the purpose of particularly promoting heat transfer within the tube. This relates to heat exchanger tubes installed with

Configuration of conventional example and its problems Figure 3 shows a conventional heat exchanger tube in which a promoting impeller is inserted inside the heat exchanger tube.
An impeller 8 is attached to the inside of the tube by a support rod 9, and the rotation of the impeller 8 generates disturbance in the fluid, thereby promoting heat transfer within the tube. However, in this case, the support rod 9 disposed at the center of the impeller 8 becomes a large resistance to the refrigerant flowing inside the heat exchanger tube. Therefore, in order to flow a certain amount of refrigerant, a larger refrigerant pump or compressor is required compared to the case where the impeller 8 is not installed, so the power used increases. In addition, in the conventional impeller 8, there is inevitably a gap between the inner wall of the heat transfer tube 7 and the tip of the impeller 8, so the flow of the refrigerant in the heat transfer tube becomes a gas-liquid two-phase flow. In this case, especially when the flow becomes circular, the liquid refrigerant passes through this gap, so the impeller 8 does not have enough rotational force to disturb the liquid refrigerant, so it plays an effective role in promoting heat transfer. not accomplish. Furthermore, in the conventional example, since the support rod 9 of the impeller 8 is present, there are restrictions on the mounting location, and accuracy in positioning the center of the support rod 9 is also required, resulting in low productivity.

OBJECTS OF THE INVENTION The present invention has been made in view of the above-mentioned conventional drawbacks, and aims to minimize the pressure loss due to the installation of the impeller, and to downsize and save labor in a heat exchanger.

Structure of the Invention The present invention has an outer diameter of an impeller for promoting heat transfer, which has an opening in the center and a row of blades arranged on the circumference, than an inner diameter of a mounting adapter for the impeller for promoting heat transfer,
The impeller for promoting heat transfer is rotatably supported within the tube.

With the above configuration, the impeller for promoting heat transfer rotates, so no dead area is generated in the downstream part of the impeller, and this rotational motion induces a flow with a swirling component in the fluid flowing inside the heat transfer tube. This increases the heat transfer area and promotes heat transfer due to the swirling component flow.

DESCRIPTION OF EMBODIMENTS Below, the structure of a heat exchanger tube into which a heat transfer promoting impeller according to the present invention is inserted will be described with reference to the drawings.

FIG. 1 shows an embodiment of a heat transfer tube into which an impeller for promoting heat transfer according to the present invention is inserted. Further, FIG. 2 shows the main body of the impeller. As shown in the figure, the impeller 2 has an opening 3 at its center, and a plurality of blades 4 that are curved with respect to the flow direction of the refrigerant are arranged at its circumference.

The impeller 2 according to the present invention is attached to the inside of the heat exchanger tube 1 using impeller attachment adapters 5 and 6. The impeller 2 and the adapters 5 and 6 are not in complete contact with each other, and the structure is such that the impeller 2 can rotate.

Since the impeller 2 for promoting heat transfer according to the present invention has the above configuration, when the refrigerant flowing in the heat transfer tube is a single-phase flow, a portion of the refrigerant flows through the opening 3 at the center of the impeller 2. The flow is constricted, which causes turbulence in the fluid. and arranged around the circumference of the impeller 2,
By the blades 4 which are curved with respect to the flow direction of the refrigerant,
At the same time as a spiral flow is generated along the inner wall of the heat exchanger tube 1, turbulence is generated in the fluid due to the rotational action of the impeller 2 caused by the flow of the refrigerant.
In-pipe heat transfer is promoted.

Next, when the refrigerant flow is a gas-liquid two-phase flow such as an annular flow, the gas phase flows through the opening 3 at the center of the impeller 2, so the impeller 2 may act as a flow resistance for the gas phase. gender is small. Furthermore, since the liquid phase passes through the circumferential portion of the impeller 2 where the blades 4 are arranged, disturbance occurs in the liquid phase due to the same effect as in the case of single-phase flow. the result,
In the case of gas-liquid two-phase flow, heat transfer within the tube is also promoted.

When installing the impeller of the present invention, there is no restriction on the installation location as long as the impeller 2 and the impeller support adapters 5 and 6 have a width as shown in FIG. This can eliminate restrictions on installation locations. In addition, Figures 1 and 2
In the figure, arrows indicate the direction of coolant flow.

Effects of the Invention As described above, the heat transfer tube in which the impeller for promoting heat transfer according to the present invention is inserted minimizes the pressure loss due to the installation of the impeller, and has an effective heat transfer promoting effect even for gas-liquid two-phase flows. have. Furthermore, since the impeller for promoting heat transfer rotates, no dead area is generated in the downstream part of the impeller, and this rotational motion induces a flow with a swirling component in the fluid flowing inside the heat transfer tube. The effect of increasing the heat transfer area and promoting heat transfer by the swirling component flow is large, and the practical effects of the present invention are extremely large.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view schematically showing a heat transfer tube into which the impeller for promoting heat transfer of the present invention is inserted, FIG. 2 is a perspective half-sectional view of the impeller for promoting heat transfer of the present invention, and FIG. It is a perspective view schematically showing a heat exchanger tube into which a conventional impeller is inserted. 1... Heat exchanger tube, 2... Impeller, 3... Opening at the center of impeller, 4... Blade.

Claims (1)

[Claims] 1. The outer diameter of a heat transfer promoting impeller with an opening in the center and a row of blades arranged on the circumference is smaller than the inner diameter of the attachment adapter for the heat transfer promoting impeller, and the heat transfer promoting impeller is A heat transfer tube rotatably supported within the tube.