JPS5918391A - Heat exchanger - 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 This invention relates to heat exchangers for cooling and heating, and in particular to highly efficient heat exchangers.

It is well known that in heat exchangers a fluid at one temperature level is introduced and passed through tubes which are exposed to a heat receiving medium, such as air. The fluid is then collected at a second temperature water rate for recirculation. The rate of heat exchange usually depends on the dimensions of the heat exchanger and the type of heat receiving medium used therein.

Thus, if the amount of heat exchange is to be increased, it is often necessary to increase the size of the heat exchanger or to make appropriate changes to the heat receiving medium. It is also well known that liquid moving along the inner wall surface of a heat exchanger is generally in a laminar flow state.

This type of flow has a limiting effect on the amount of heat transferred through the tube wall to the heat receiving medium.

It is thus desirable to provide a heat exchanger that promotes turbulence in order to increase fluid contact at the walls of the heat exchanger to increase its heat transfer capacity without increasing the dimensions of the heat exchanger. .

Important among the several objects of this invention is the use of heat pumps to deflect the normal flow of fluid within a conduit or to create turbulent effects within the conduit along a path longer than the length of the fluid flow conduit. A novel heat exchanger in which a displacement device is provided in the conduit to increase the heat transfer capacity of the exchanger and to produce an acceleration or deceleration effect on the fluid flow to increase the heat transfer capacity of the heat exchanger. The object of the present invention is to provide a novel heat exchanger in which the conduits are provided with a constricted or widened section that facilitates this.

Other objects and characteristics will be partly obvious and partly pointed out below.

According to the invention, the heat exchanger has a fluid inlet chamber and an outlet chamber, which chambers communicate with each other by a number of conduits connecting them. The conduits have, for example, a circular or +1-round cross-section and can have inlet and outlet openings of different shapes and dimensions depending on the desired capacity of the heat exchanger. Thus, an inlet or outlet section with a constricted or expanded section has an accelerating or decelerating effect on the fluid flow that promotes the desired cooling or heating effect.

The inlet and outlet chambers have an outer shell that is hermetically secured to the headboard to form a substantially closed space.

Each headplate includes an opening into which the end portion of the conduit is inserted.

A hermetic tight connection between the end portion of the conduit and the headboard is obtained by a brazing or cementing connection that seals the end portion to the headboard. The array of slat-like fins along the length of the conduit enhances heat exchange between the conduit and the heat receiving medium flowing across or surrounding the conduit.

A fluid flow deflection device, such as a baffle or zigzag member, located inside each conduit displaces the normal fluid flow within the conduit to direct the fluid through a path that is longer than the length of the conduit. Creates fluid turbulence within the conduit. The fluid flow deflection device thus increases the contact area of the fluid portion with the inner surface of the conduit. Energy dissipation and recovery is therefore enhanced.

Embodiments of the invention will be described in detail below with reference to the drawings.

As shown in the drawings, particularly FIGS. 1 and 3 thereof, the evaporator type heat exchanger comprises an inlet chamber 5 with an inlet connection 7 and an outlet chamber 6 with an outlet connection 8. Chambers 5 and 6 are made of any suitable metal, plastic or sesmic that can withstand the temperatures and pressures applied to the heat exchanger.

Chambers 5 and 6 have head plates 9 and 10, respectively, whose edge portions are brazed and rubberized to the periphery of the body of chambers 5 and 6, as indicated at 16 in FIG. 4 for chamber 6. It is sealed tightly using a sealing material, etc. The edges of chambers 5 and 60 are thus sandwiched between the folded edges of head plates 9 and 10. Openings are formed in the head plates 9 and 10 for receiving the end portions of the conduits 11 and 120. For example, the head plate 10 has a circular insertion opening for the conduit 11 and an oval insertion opening for the conduit 12, as shown in FIG. For simplicity, only the center of the other openings in the headboard is shown with a cross. Here, conduit 12 has a constricted inlet opening and an outlet opening, and conduit 11 has a constricted inlet opening and an unconstrained outlet opening. The end portions of the conduits 11 and 12 are also brazed at the openings of the head plates 9 and 10, as shown at 15 in FIG. Openings 9 and 10 also allow adjustment of conduits 11 and 12 relative to these headboards.

Regularly spaced rows of fins or vanes 14 are provided along conduits 11 and 12 generally perpendicular to the axes of these conduits.

The fins 14 increase the heat transfer area, the amount and spacing of which is determined according to the requirements of the heat transfer system.

Each of conduits 11 and 12 includes a device for deflecting fluid flow within the conduit along a predetermined path VC over the length of the conduit. Flow deflection device is code 1
It can consist of a baffle arrangement as shown in 5.

The baffle arrangement 15 includes a central support member with a staggered arrangement of spaced apart segments, such as semicircular shapes. As clearly shown in FIG. 4, a rod-shaped separating member 16 is arranged in the central part of the heat exchanger and extends from the head plate 9 to the head plate 10 at a height. Thus, the separating member 16 separates the inlet chamber 5 and the outlet chamber 6.
This helps maintain the spacing between the heat exchangers and provides rigidity to the structure of the heat exchanger.

During operation of the heat exchanger, fluid flows into the inlet pipe (inlet connection) 7 of the inlet chamber 5 and into the inlet openings of the conduits 11 and 120. Fluid typically flows through the heat exchanger tubes in a path that follows the axis of the tubes. However, according to this embodiment, as the fluid flows through conduits 11 and 12, it impinges on segments of baffle arrangement 15 and its flow path follows the path determined by this baffle arrangement in conduits 11.12. deviation from the axis of Thus, for example, fluid flow in conduits 11 and 12 is repeatedly deflected over the circumference of the segments rather than following a straight path. Thus, the fluid flow path is longer with the baffle arrangement than it would be without it. The fluid therefore remains in the conduit for a long time and its turbulence makes extensive contact with the inner surface of the conduit, which can increase energy dissipation or recovery.

FIG. 5 shows another embodiment of the invention suitable for use in a heat sink for a vehicle such as an automobile.

The heat exchanger of FIG. 7 includes an upper tank 17 with a head plate 22 and a lower tank 24 with a head plate 23. Headboard 22 and 2
6 has a protrusion as shown at 26, which is a complementary shaped receiver for the vessels 17 and 24. υ, whereby a leak-free seal between the head plates 22 and 26 and the outer shells of the vessels 17 and 24 is easily achieved.

The upper tank 17 has a filling opening 18 through which the required amount of coolant is initially admitted for heat exchange. Tank 17 further has an inlet pipe 19 which receives heated coolant from a prime mover (not shown). Lower tank 24 has an outlet connection 25 for supplying coolant to the prime mover. Tanks 17 and 24 are connected by a number of vertical conduits, indicated by line 21 in FIGS. 5 and 6 and illustrated in detail in FIG. communicate with each other. Conduit 21 preferably has a uniform circular cross section;
The end portions of 7 engage complementary shaped openings in head plates 22 and 25, respectively, to provide a hermetic seal similar to that described for the embodiment of FIG. The JX'R21 has a row of laterally extending fins or vanes 20 and is further provided with a sump device to deflect the flow of fluid within the conduit into a predetermined path.

Example U: A flow deflection device t includes a zigzag member 30 as shown in FIG. 8, and a flow deflection device as illustrated in FIG. includes.

In operation of the embodiment of FIG. 5, coolant from the prime mover passes through inlet pipe 19 to upper tank 17 at a relatively high temperature level and passes downwardly through conduit 21 to lower tank 24. As the water (coolant) descends into the conduit 21 having the zigzag member 60, the fluid flow is deflected by the zigzag member 60. A turbulent flow of fluid is thus created in the conduit 21 which enhances the transfer of heat from the coolant through the inner surface of the conduit 21 towards the exterior of it and towards the fin vanes 20 which are exposed to the outside atmosphere and receive further heat. let It should be noted that the zig-zag member 60 has a cross-sectional extent such that it does not unduly impede the flow of coolant in the conduit 21 and that the particular arrangement of such a zig-zag member prevents the flow of coolant from the upper reservoir 17 to the lower reservoir 24. Determined based on desired coolant flow rate.

Coolant is thus present in the lower tank 24 at a relatively low temperature level, which is transferred through the outlet connection 25 to the prime mover where it is heated up and is again pumped through the inlet pipe 19 to the upper tank. 17, thus repeating the flow cycle.

As the coolant descends through the conduit 21 with the baffle arrangement 29, it follows a path that repeatedly traverses the axis of the conduit 21 in a manner similar to a sinusoid across the axis. Thus, cooling within the conduit 21 is reduced. The agent travels along a path υ longer than the length of the conduit and is subjected to a mixing action by the baffle arrangement 29, all of which is directed from the coolant through the inner surface of the conduit 21 to its outer surface and towards the fin vanes 20. Enhances heat transfer.

From the above description, it can be seen that several objects of the present invention are achieved and other advantages are obtained. Since the configuration described above can be modified in various ways without departing from the gist of the invention, All matter illustrated in the figures is set forth by way of illustration and not limitation.

[Brief explanation of the drawing]

Fig. 1 is an elevational view of a heat exchanger incorporating one embodiment of the present invention, Fig. 2 is a cross-sectional view taken along line B-D in Fig. 1, Fig. 6 is a side view of Fig. 7, and Fig. 4 is a sectional view taken along line B-D in Fig. The drawings are a sectional view taken along line A-A in FIG. 1, FIG. 5 is an elevational view of another embodiment of the invention, FIG. 6 is a side view thereof, and FIG. Figures 8 and 9 are detailed cross-sectional views along line D--D of Figure 7 showing conduits with different flow deflection devices. In the drawing, 5 is the entrance chamber, and 6 is the exit chamber. 11 and 12 are conduits, 15 is a displacement device, 16 is a separation member, 17 is an inlet chamber, and 21 is a conduit. 24 is an exit chamber, and 29 and 30 are displacement devices. -44°Figure 6

Claims (1)

[Claims] 1. An inlet chamber and an outlet chamber for a fluid, and a number of conduits connected to said inlet and outlet chambers at both end portions, such that said inlet and outlet chambers are connected by said conduits. The conduits are capable of communicating with each other and include deflection devices within the conduits for deflecting fluid flow within the conduits along predetermined paths that promote turbulent flow of fluid within the conduits. and a heat exchanger having substantially the entire length thereof. 2. The heat exchanger of claim 1, wherein the deflection device includes a baffle member along the length of the conduit. 3. a central support member extending substantially the length of the conduit so that the deflection device deflects the flow of fluid within the conduit along a predetermined path that exceeds the length of the conduit; 2. A heat exchanger according to claim 1, comprising segments arranged alternately along the length of the heat exchanger. 4. The heat exchanger according to claim 6, wherein the segment is semicircular. & A heat exchanger according to claim 1, wherein the deflection device includes a zigzag member extending along the length of the conduit. & as claimed in claim 1, having a central separation member that engages the inlet and outlet chambers to provide a constant separation distance between the inlet and outlet chambers and to provide rigidity to the heat exchanger. Heat exchanger. 2. The heat exchanger ◎8 according to claim 1, in which a predetermined group of conduits has a circular cross section and another predetermined group of conduits have a non-circular cross section; 2. A heat exchanger as claimed in claim 1, having a defined inlet opening. 2. A heat exchanger according to claim 1, in which the conduits have a constricted outlet opening. 10. Heat exchanger according to claim 1, in which the conduits have enlarged inlet openings. 1t A heat exchanger according to claim 1, characterized in that the conduit has an enlarged outlet opening.