JPS6051035B2 - Plate heat exchanger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a plate heat exchanger, in particular a plate heat exchanger for viscous fluids.

The plate 1 generally used in a plate heat exchanger is
As shown in Fig. 1, it consists of a heat transfer surface 2, a fluid distribution surface 3, and a passage hole 4. By stacking a plurality of plates 1 at a predetermined interval, the heat transfer surfaces of the plates 1 are A meandering passage is formed in the meandering passage, and after the fluid supplied from the passage hole 4 is rectified and dispersed on the fluid distribution surface 3, it is made to uniformly flow into the meandering passage to perform heat exchange. Incidentally, for the spreading of the fluid from the passage holes 4 to the heat transfer surface 2, that is, for rectification and dispersion, only the fluid distribution surface 3 is sufficient for low viscosity fluids, but for example, for viscous fluids such as engine lubricating oil, etc. When heat exchange is performed by supplying a large fluid to the heat transfer surface 2, the fluid distribution surface 3 alone cannot perform sufficient rectification and dispersion, and the fluid is distributed uniformly over the entire flow width of the heat transfer surface 2. It is difficult to flow and tends to flow unevenly.

That is, the flow flows through the passage hole 4 in the order of arrows 5, 6, and 7 in FIG.
The flow velocity gradually decreases as the distance from the fluid increases.Particularly in the case of viscous fluids, the deviation of the flow velocity is significant and the flow tends to drift, and the width of the main flow area narrows, resulting in an apparent dead space.

As a result, the apparent upstream velocity increases, pressure loss increases, and dead space is created, resulting in a decrease in the amount of heat transfer.
When the heat transfer coefficient becomes a low value, such problems occur.

In view of the above-mentioned drawbacks of conventional plate heat exchangers, the present invention improves and eliminates them, and provides a plate heat exchanger suitable for viscous fluids.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the structure of the present invention shown in the drawings will be described below.

In Fig. 2, 10 is a plate forming a fluid passage for viscous fluid, 11 is a heat transfer surface of the plate, 12 is a packing fitted around the plate, and 13, 14, 15, and 16 are provided at the four corners of the plate 10. Fluid passage hole, 17, 1
8 is a fluid distribution surface.

Reference numerals 19 and 20 indicate weirs formed at both ends of the heat transfer surface 11 of the plate 10, consisting of a concave portion a and a convex portion.
Reference numeral 20 indicates the concave portion a and the convex portion of the weir provided on each of the two plates when the plate 10 and another plate 10' are stacked in an inverted state to form a flow path between the two plates. As shown in FIG. 3, the flow path 21 formed by Of the passage holes, those near the holes 14 and 16 used as fluid inlet and outlet holes are widened, and the inlet and outlet holes 1 are widened.
4 and 16, the narrower it becomes.

In the above configuration, for example, the plates 10, 10'', 1''
, 1"" are alternately reversed and stacked, one fluid m passes between the plates in the direction of the broken line in FIG. The plates are arranged in such a way that the fluid exchanges heat through the plates during its passage.

Then, the flow path 21 formed between each plate by two weirs 19, 20 provided on each plate 10, 1'', 1'', 10'''' is located near the fluid inlet/outlet 22 as shown in FIG. In general, the flow becomes wider as it gets farther from the inlet/outlet.For this reason, the shortest course from the passage hole to the heat transfer surface has a larger flow resistance than the others, and conversely, the flow resistance is the smallest in the longest course, so A well-balanced flow rate distribution can be obtained on the entire plate heat transfer surface, and a decrease in heat transfer coefficient can be prevented, especially when a highly viscous fluid is flowed through the flow path.As explained above, this invention The plate heat exchanger consists of a heat transfer surface, a fluid distribution surface, and a passage hole that forms an inlet and an inlet for the fluid.At both ends of the heat transfer surface of the plate, there are channels sandwiched in the vicinity of the inlet and outlet of the fluid. The weir for fluid distribution is configured to widen as it gets farther from the inlet/outlet, which prevents short baths of highly viscous fluids, allows the channel width to be used to its fullest extent, and improves heat transfer coefficient. It can be used as a plate heat exchanger for highly viscous fluids and can exhibit excellent performance.

[Brief explanation of drawings]

Fig. 1 is a front view of a plate used in a conventional plate heat exchanger, Fig. 2 is a front view of a plate used in a plate heat exchanger according to the present invention, and Fig. 3 is a front view of a plate used in a plate heat exchanger according to the present invention. A sectional view showing two such plates stacked together and cut at the weir part, FIG. 4 is a perspective view showing an example of plate knitting, and FIG. 5 is a weir part when the plates are knitted as shown in FIG. 4. FIG. 10... Plate, 11... Heat transfer surface,
13, 14, 15, 16... Passage hole, 17,
18...Fluid distribution surface, 19,20...
Weir, a... Concavity, b... Protrusion, M, n
······fluid.

Claims (1)

[Claims] 1. At both ends of the heat transfer surface of the plate that constitutes the plate heat exchanger, which consists of a heat transfer surface, a fluid distribution surface, and passage holes forming the fluid inlet and outlet, the flow path narrows near the fluid inlet and outlet, A plate heat exchanger characterized by being provided with a fluid distribution weir configured to become wider as it gets farther from an inlet/outlet.