JPS6013980A - Warm-up device for diesel engine - Google Patents

Abstract

PURPOSE:To save energy by a method wherein a heat accumulator, accumulating the heat of exhaust gas of the engine or the heat of outlet cooling water through heat medium, is connected in series to a heat exchanger for warm-up to provide a heat medium circulating path. CONSTITUTION:During the operation of the engine, valves 9, 10 are closed, the valve 11 is opened and the thermal oil circulating path is formed by operating a pump 8. Thermal oil, entered into an exhaust gas economizer 6, enters into the heat accumulator 7 after receiving the heat of the exhaust gas and becoming high in the temperature thereof, the heat thereof is deprived therein and circulates through the pump 8 and the valve 11. Upon warming-up before the starting of the engine, the valves 9, 10 are opened and the valve 11 is closed to form warm-up circulation path while the oil, heated by the heat accumulator 7, is sent into a warm-up heater 3 by the pump 8, heat thereof is exchanged with he heat of the cooling water or lubricating oil passing through the engine 1 and the pump 4 to heat it and, then, is returned again into the heat accumulator 7. On the other hand, the engine 1 is warmed up by the cooling water or the lubricating oil, heated by the heater 3. According to this method, the energy may be saved and the effect of this method in high especially in case when it is applied to submarines.

Description

[Detailed Description of the Invention] The present invention relates to a warm-up device for a diesel engine, in which the waste heat from the exhaust gas of the diesel engine is stored and the stored heat is used to preheat the engine at the time of startup. This relates to a warm-up device for a diesel engine.

- Generally speaking, diesel engines are equipped with a warm-up device that warms up the engine to a temperature at which it can be started.

A warm-up device is usually provided in a cooling water system and a lubricating oil system for a diesel engine. Here, the conventional warm-up device installed in the cooling water system will be explained with reference to Fig. 1.
A warm-up heater 3 is provided so as to bypass the cooler 2, and a pump 4 is operated as a warm-up operation before starting the main engine.
Cooling water is supplied from the expansion tank 5 to the warm-up heater 3
The cooling water is circulated through the diesel engine 1 to warm it up to a temperature at which the engine can be started.
This warm-up heater 3 is normally heated by steam from a boiler or an electric heater.

Generally, when the diesel engine 1 is warmed up, it is impossible to utilize waste heat by an exhaust gas economizer or the like since the engine is not yet in operation.

As mentioned above, the conventional warm-up device uses steam or electricity to warm up the engine before starting the engine, which wastes valuable fuel or energy each time the engine is warmed up.

In particular, fuel is used as an engine warm-up system for applications where the engine is started frequently, such as main engines for work vessels such as tug boards, side thruster drive engines for work vessels equipped with dynamic positioning devices, and main engines for submersible vessels. Also, the power consumption is large.

The present invention was made in order to eliminate the conventional problems as described above, and stores the energy that is wasted outside through exhaust gas or cooling water during diesel engine operation, extracts it as a heat source when warming up, and wastes it. The purpose is to solve the above problems by making heat available.

In order to achieve the above object, the present invention provides a circulation path for cooling a diesel engine through cooling water passing through a cooler that cools feed water, and a warm-up heat exchanger is provided in parallel with the cooler. In a diesel engine warm-up device, a heat medium circulation path is provided in which a heat storage device that stores heat from diesel engine exhaust gas or cooling water at the exit of the diesel engine via a heat medium is connected in series with a warm-up heat exchanger. This feature constitutes a warm-up device for a tossle diesel engine.

In other words, the waste heat generated during operation prior to engine startup is stored as a heat source for warming up the engine, using a heat storage device or a reversible chemical reaction, and this heat is extracted and used as a heat medium when the engine is warmed up. It is characterized by the fact that it can be warmed up economically by using heat transfer oil (thermal oil) in combination with an inexpensive heat storage device.

The present invention can be widely applied to warm-up devices for diesel engines that are frequently started, and in the field of ships, it can be applied to submersibles, various types of operating vessels, and the like.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 2 is a system diagram showing one embodiment of the present invention, in which a warm-up system is provided that uses exhaust gas from the engine as a heat source for the warm-up heater 3. In this figure, the same reference numerals are given to the same members as those shown in FIG. 1.

The warm-up system is composed of an exhaust gas economizer 6, a heat storage device 7, a thermal oil circulation pump 8, and a warm-up heater 3 installed in the engine exhaust pipe, which are connected in series to form a heat medium circulation path. are doing. In addition, a valve 10 that operates in the same manner is placed in a position that bypasses the circulation path before and after the exhaust gas economizer 6, and a valve 10 that is opened during warm-up before starting the engine and closed while the engine is running is placed in a position that bypasses the circulation path before and after the exhaust gas economizer 6. and the warm-up heater 3-kichi.

Furthermore, the thermal oil circulation pump 8 has a valve 11 that is closed during warm-up before starting the engine and is left open during engine operation.
and the valve 10 and the circulation path returning from the warm-up heater 3 to the exhaust gas economizer 6.

Next, the operation based on the above configuration will be explained.

During engine operation, valves 9 and 10 are closed, valve 11 is opened, and pump 8 is operated to form a circulation path for the thermal oil. The thermal oil that has entered the exhaust gas economizer 6 receives heat from the engine exhaust gas, and the high-temperature oil enters the heat storage device 7.The heat is carried away by the heat storage device 7, passes through the pump 8, passes through the valve 11, and returns to the exhaust gas economizer 6. to go into.

During warm-up before starting the engine, valves 9 and 10 are opened and valve 11 is closed to form a warm-up circulation path.

That is, the thermal oil warmed by the heat storage device 7 is sent to the warm-up heater 3 by the pump 8, and is heated by the warm-up heater 3 by exchanging heat with the cooling fresh water or lubricating oil passing through the engine 1 and the pump 4. , returns to the heat storage device 7 again. On the other hand, Shimizu (lubricating oil)
is lined up in a path passing through the engine 1, and the fresh water (lubricating oil) warmed by the warm-up heater 3 warms up the engine 1.

FIG. 3 shows another embodiment of the present invention, in which the same parts as those shown in FIG. 2 are designated by the same reference numerals.

The difference from the embodiment shown in FIG. 2 is that the valve is eliminated and a warm-up heater is provided with a heat storage type heater 12 having a heat storage function. Other operations are similar to those shown in FIG.

According to the present invention, energy saving is achieved by utilizing waste heat of engine exhaust gas.

In particular, when the present invention is applied to a submersible, the effects are significant.

Further, when thermal oil is used as a heat medium, high-temperature heat transfer is possible while keeping the heat medium pressure at atmospheric pressure, and the warm-up device is simplified.

In the above embodiment, exhaust gas from the engine is used as the heating source for the heat medium, but cooling water from the engine outlet may be used by storing heat in a heat storage device.

Of course, the warm-up device of the present invention can be modified as appropriate without departing from the gist of the present invention, such as being able to be used as a heat source for heating etc. for products that use engines that operate intermittently. It is.

[Brief explanation of drawings]

FIG. 1 is a system diagram of a conventional engine warm-up device, FIG. 2 is a system diagram of a warm-up device according to an embodiment of the present invention, and FIG. 3 is a system diagram of another embodiment of the present invention. 1. Diesel engine, 2. Cooler, 3. Warm-up heater, 4. Pump, 5. Expansion tank, 6. Exhaust gas economizer, 7. Heat storage device, 8.
Thermal oil circulation pump, 9.10.11...valve, 1
2. Heat storage type heater. Figure 1 No.? figure

Claims (1)

[Claims] Diesel water is passed through a cooler that cools the feed water.
A warm-up device for a diesel engine is provided with a circulation path for cooling the diesel engine, and - a warm-up heat exchanger is provided in parallel with the cooler. A warm-up device for a diesel engine, characterized in that a heat medium circulation path is provided in which a heat storage device for storing heat of cooling water via a heat medium is connected in series with the warm-up heat exchanger.