JPH0425430B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a heat exchanger used for recovering exhaust heat from a combustion device such as an engine.

Conventional configuration and its problems In the past, there was a system like the one shown in Figure 1 that reflected energy conservation trends and attempted to improve overall energy efficiency by recovering waste heat from heat sources such as engines. The system extracts shaft output from an engine 1 as power, recovers waste heat in a heat exchanger 2, and discharges it through a muffler 3. However, in such a system, the heat exchanger 2 that recovers exhaust heat from the engine 1 and the muffler 3 are provided separately, which not only complicates the system, but also causes large noise transmission from the muffler 3. In order to enhance the sound reduction effect, the muffler 3 had to be made larger.

In addition, as a conventional heat exchanger for waste heat recovery,
Most of them are in the form of fins as shown in Figure 2, but
In this format, the pulsating flow effect from engine 1 is
It was difficult to make full use of it, promoting the development of a boundary layer near the heat transfer surface, and making it impossible to improve the heat transfer characteristics on the gas side, so it was necessary to make the heat exchanger larger.
Furthermore, when trying to increase the exhaust heat recovery efficiency, there was a problem in that the exhaust gas condensed, corrosion of the fin surface progressed, and the heat exchange performance suddenly decreased.

Purpose of the Invention In view of the conventional problems, the present invention aims to simplify the system configuration by integrating a muffler and a heat exchanger, and to provide a low-noise, high-efficiency exhaust gas heat exchanger. purpose.

Structure of the Invention The present invention provides a muffler and an exhaust gas pipe in the liquid part of a water chamber having an exhaust port, positions the tip of the exhaust gas pipe in the gas part of the water chamber, and surrounds the tip with an exhaust gas collision body. The lower end of this exhaust gas colliding body is opened to the liquid part in the water chamber, and the upper end is equipped with a valve that automatically opens and closes according to pressure fluctuations in the space surrounding the exhaust gas pipe. .

Description of examples A specific explanation will be given below with reference to the drawings.

FIG. 3 shows an embodiment of the heat exchanger of the present invention, in which the heat exchanger has a water chamber 5 having an exhaust port 4.
is an outer body, and the liquid part in the water chamber 5 is provided with an exhaust muffler 6 and an exhaust gas pipe 7. The tip of the exhaust gas pipe 7 is located in the gas part in the water chamber 5. An exhaust gas collision body 8 is provided so as to surround the exhaust gas collision body 8 . The lower end of this exhaust gas collision body 8 is opened to the liquid part in the water chamber 5, while the upper end of the exhaust gas collision body 8 is located in the gas part in the water chamber 5, and the upper end is opened to the liquid part in the water chamber 5. for,
An exhaust pressure valve 9 is provided which automatically opens and closes in response to pressure fluctuations in the gas phase space surrounded by the exhaust gas pipe 7 and the exhaust gas collision body 8. In addition, inside the water chamber 5, a partition plate A10, a partition plate B11, and a partition plate C each have a plurality of holes.
12, partition plate A10, partition plate B
11 is in the liquid part, and the partition plate C12 is in the gas part, and the partition plate B11 and the partition plate C12 are joined to the exhaust gas collision body 8. Furthermore, in addition to the exhaust port 4, the water chamber 5 includes an exhaust gas inlet 13, a water inlet pipe 14,
A water discharge pipe 15 is provided, and a neutralization treatment device 16 is provided downstream of the water discharge pipe 15.
Note that a hole is made at the upper end of the exhaust gas colliding body 8 for installing an exhaust pressure valve 9.
A plurality of holes are also provided in the upper part of the exhaust valve 9 to allow reverse flow, and the exhaust valve 9 is made of a lightweight, heat-resistant, and durable material.

Next, the operation will be explained. First, the fluid to be heated is sent into the water chamber 5 from the water introduction pipe 14, contacts the finned exhaust muffler 6, the exhaust gas pipe 7, the partition plate A10, the partition plate B11, the exhaust gas collision body 8, etc., and releases heat. The water is taken away and discharged from the water discharge pipe 15. At this time, if it is acidic, a neutralization treatment is performed by a neutralization treatment device 16 provided downstream. On the other hand, exhaust gas from a heat source such as an engine, which is a heating fluid, enters the water chamber 5 from the exhaust gas inlet 13, passes through the exhaust muffler 6 provided in the liquid part of the water chamber 5, and the exhaust gas pipe 7, and is efficiently It exchanges heat well with the fluid to be heated, reaches the space surrounded by the exhaust gas collision body 8, and closes the exhaust pressure valve 9 provided at the upper end of the exhaust gas collision body 8. and,
Since the exhaust gas is rapidly sent into this space, the pressure within the space increases and the liquid present between the exhaust gas collision body 8 and the exhaust gas pipe 7 is pushed down. After that, the exhaust gas that has pushed down the liquid turns into bubbles, and some of them collide with or pass through the partition plate A10 from the lower end of the exhaust gas collision body 8, and some of them collide with or pass through the partition plate A10.
The liquid portion existing between the exhaust gas collider 8 and the exhaust gas collider 8 rises, passes through the partition plate B11, and is discharged into the gas portion in the water chamber 5. At this time, the exhaust gas exchanges heat while being in direct contact with the fluid to be heated, so it is possible to obtain heat transfer characteristics that are significantly superior to those of the prior art. In addition, with regard to sound reduction characteristics, significant effects can be expected as the exhaust gas passes through the liquid.
The exhaust gas released into the gas portion in the water chamber 5 then passes through the partition plate C12 and is discharged to the outside from the exhaust port 4, but the partition plate C12 also serves as a muffler sound reduction effect. This also improves sound reduction performance. As described above, when the exhaust gas is discharged from the exhaust port 4, the pressure in the space surrounded by the exhaust gas colliding body 8 decreases due to its inertia, and the exhaust pressure valve 9 is opened, and the exhaust gas colliding body 8 and the exhaust gas pipe 7 are opened. The liquid present in between is pushed up again. The cycle described above is then repeated at high speed according to the pulsating combustion of the engine. Regarding heat transfer characteristics, not only the direct contact between the exhaust gas and the specific heating fluid but also the exhaust gas passing through the exhaust muffler 6 and the exhaust gas pipe 7 at high speed suppress the development of a boundary layer and improve the heat transfer coefficient on the gas side. It can also be expected to have the effect of increasing In addition, the structure is such that the pulsation of the engine is actively utilized, and by fluctuating and stirring the liquid in the water chamber 5, the heat transfer coefficient on the water side can also be increased. Furthermore, the fins of the exhaust muffler 6, the partition plate B11, and the partition plate C12 are for the specific heating fluid to effectively remove heat.

In addition, regarding the sound reduction characteristics, there is not only the effect of the exhaust gas passing through the liquid and the multi-stage expansion type muffler effect by the partition plate B11 and the partition plate C12, but also the sound insulation effect by surrounding the exhaust muffler 6 with liquid. Improvements can also be expected.

Furthermore, in the past, when trying to increase the efficiency of exhaust heat recovery from the engine, condensed water was generated and corroded the heat exchanger surface, but in the heat exchanger of the present invention, condensed water is not generated. The liquid is also recovered from the water discharge pipe 15, and if the liquid is acidic, it can be neutralized by the neutralization treatment device 16.

Effects of the Invention As explained above, according to the present invention, a muffler type exhaust gas heat exchanger can be obtained, and the system can be simplified. Regarding heat transfer characteristics, the effect of direct contact between the exhaust gas and the heated fluid, the improvement of the heat transfer coefficient on the gas side due to the exhaust gas passing through the exhaust muffler and exhaust gas pipe at high speed, and the heat transfer on the water side due to water agitation. By improving the coefficient, significantly superior heat transfer performance can be expected. Furthermore, with regard to sound reduction characteristics, significant sound reduction effects can be expected due to the effect of the exhaust gas passing through the liquid, the multi-stage expansion type muffler effect due to the partition plate, and the improvement of sound insulation due to the liquid surrounding it.
Further, the treatment of condensed water can be easily performed using the heat exchanger of the present invention.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of an engine system equipped with an exhaust heat recovery heat exchanger, FIG. 2 is a configuration diagram of a conventional fin type heat exchanger, and FIG. 3 is a configuration diagram of a heat exchanger of the present invention. 5...Water chamber, 6...Exhaust muffler, 7...Exhaust gas pipe, 8...Exhaust gas collision body, 9...Exhaust pressure valve.

Claims (1)

[Claims] 1. A muffler and an exhaust gas pipe are provided in the internal liquid part of the water chamber having an exhaust port, the tip of the exhaust gas pipe is located in the gas part in the water chamber, and the tip is further surrounded by an exhaust gas collision body to prevent the exhaust gas from colliding with each other. The lower end of the body is opened to the liquid part in the water chamber, and the upper end of the exhaust gas colliding body is located in the gas part in the water chamber, and the upper end of the body is opened to the liquid part in the water chamber. A heat exchanger equipped with a valve that opens and closes.