JPS5820910A - Compound engine system - Google Patents

Abstract

PURPOSE:To improve efficiency of a Rankine engine for an improvement of a fuel consumption, by providing a combustor which heats a varporizer in a supplemental manner, in a compound engine having an auxiliary engine which is operated by waste heat of a main engine. CONSTITUTION:A Rankine engine is constituted with a vaporizer 3, an expander 4, a condenser 5 and a feed liquid pump 6. A combustor 12 heats the vaporizer 3 in a supplemental manner and is provided in a rear flow of a gathering part 2a of an exhaust pipe 2 of a main engine 1. When a temperture of exhaust gas is low, vapor having a sufficient temperature is generated and the Rankine engine can be actuated as the combustor 12 is actuated, high temperature gas is generated in addition to the exhaust gas and the vaporizer 3 is heated. Even when the main engine 1 is being suspended, the combustor 12 and the expander 4 are actuated and either actuation of an air conditioner or a charge of a battery is carried out. A fuel consumption is improved like this.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of a combined engine system having a Rankine engine as an auxiliary engine operated by exhaust heat of a main engine such as an internal combustion engine.

As a conventional composite engine system of this type.

There is something like the one shown in the tllK 0 example 41 open @ 5]
-3'141484 is disclosed at @.

That is, the steam produced by the heat exchanger provided in the exhaust pipe 2 of the main engine 1 is 113. 4. An expander that generates steam from aS and extracts power from it. This expander 4 also condenses the low pressure steam discharged into the steam generator S, and the condensed working fluid is sent to the steam generator S.
The Rankine engine is mainly composed of a liquid supply pump that supplies K.

1 is a power transmission device such as a gear or a fluid coupling, which transmits the power generated in the expander 4 to the main engine 1, operates the main engine 1, and improves the fuel efficiency of the main engine 1. Furthermore, the Rankine engine drives the Punpretsusa $1 generator for the F:I engine and recovers the exhaust energy of the main engine 1, further improving the fuel efficiency of the engine system. In addition, 1.
is an oxidation catalyst for exhaust gas purification, and 11 is an exhaust bypass/(ruple) that partially bypasses the exhaust gas when the exhaust flow rate is large.

In such a conventional combined engine system, the Rankine engine was operated only by the exhaust heat of the main engine 1, so in particular, the platform applied as a power source for passenger cars was (a) Rankine engine. This is the operating range in which the engine can be operated efficiently (the effect of improving fuel efficiency is small.

(P) Since the expander 4 directly drives the air conditioner compressor operation and battery charging when the vehicle is stopped, the main engine 1 must be used under extremely inefficient conditions (the coefficient of performance of the cooler is 0 when idling). .25° (3% power generation efficiency for battery charging), poor fuel efficiency as an engine system, and also generates a lot of noise during operation.

There was a problem.

This invention was made with attention to these conventional problems, and aims to solve the above problems by providing a combustor that supplementally heats the steam generator of the Rankine engine. .

Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 2 is a diagram showing an embodiment of the present invention.

In FIG. 2, the same reference numerals as in FIG. 1111 indicate the same constituent parts, so the explanation thereof will be omitted. Reference numeral 12 denotes a combustor that auxiliary heats the steam generator 3, and this combustor 1 is provided downstream of the collection 112a of the exhaust pipes 2 of the main engine 1. The main structure of the combustion St2 is the fuel injection valve 13. It consists of an air pump 141, a spark plug 15, etc. Furthermore, this embodiment shows an example in which power is transmitted from the expander 4 to the power transmission device T via the clutch 16, and to the punch pump 8 via the clutch 17. In addition, a steam pulp 1s is provided at the steam inlet of the expander 4, an exhaust temperature sensor 1s is provided in the exhaust pipe 2 to detect the exhaust temperature, and a steam temperature sensor is provided in the steam generator 113 to detect the steam temperature. Each of these is provided with an O. The clutch 16 is closed when both the main engine 1 and the Rankine engine are operating, and the clutch 11 is closed only when the air conditioner compressor operating switch is on.
0 In passenger car engines, the load conditions generally used are low, and the 4I
The average horsepower in city driving is about one-tenth of the maximum horsepower. Therefore, the engine exhaust temperature is also low, for example about 200-600°C. When the exhaust gas temperature is relatively high, for example, 400° C. or higher, the Rankine engine can be efficiently operated by the exhaust heat. On the other hand, under conditions where the exhaust temperature is low, the combustor 12 operates and high-temperature gas is generated in addition to the exhaust gas to heat the steam generator 3, which generates steam at a sufficient temperature to operate the Rankine engine. Can be done. Also, even if main engine 1 is stopped, if the air conditioner compressor operation switch is ON or the manual switch is OFF.
When N, the combustor 12 operates, generates sufficient steam in the steam generation 1is, and the expander 4 operates. Therefore, the air conditioner is operated or the battery is charged.

In addition, in FIG. 2, if the fuel injection valve 130 and spark plug IS are provided so that the exhaust manifold 2b is used as a combustion cylinder, the entire system becomes compact and space can be used effectively.

FIG. 3 shows an example of a control circuit. This control circuit is based on the exhaust temperature T@ of the main engine 1 and the set temperature Tr@t.
Comparator 21. Comparator 21. Comparator 21. Comparator 21. Comparator 21. Comparator 21. Comparator 21. Steam temperature T of steam generation Wh3
A comparator 22 which compares s with a set temperature Trdl and outputs an output when the steam temperature T is equal to or higher than the set temperature T. Air conditioner switch SA or manual switch SM is O
3. An OR circuit that outputs an output when N. The ORI circuit which outputs when the output of this OR circuit 23 or the output of the comparator 21 is input 0RIIi12 which outputs when the output of the ORI circuit 2S or 7 tassel switch 8c is ON
S, the output of this OR circuit 2S and the comparator! It consists of ANDIII2. which outputs an output when the output of is input.

Next, the operation shown in FIG. 3 will be explained.

First, the exhaust temperature T@ of the main engine 1 is the set temperature Trd1
In the following cases, or the air conditioner switch SA.

When the manual switch S is ON, 0R81 road 2
Since power is input to 4, its output becomes 1''-, and combustion 1) 12 is turned on to supplementally heat the steam generator IIs shown in Fig. 2. On the other hand, the steam temperature T of steam generator II3 is the set temperature. If it is larger than Tr@fl, the output of the comparison IH2 becomes "1" and is input to one terminal of the AND circuit 26.At this time, either the air conditioner switch SM, the manual switch SM#7 or the accelerator switch 8c is activated. When it is ON, ``@]'' is input to the other terminal of the AND circuit 2@, so the output of the AND circuit 2 becomes ``1'', thereby opening the steam pulp 1@ and operating the Rankine engine.

No. 411 shows another embodiment of the present invention, in which the exhaust heat of the main engine is transferred to the air by a heat exchanger 941, the heated air is guided to the combustor 12 by the air distribution pipe 42, and the heated air is used to generate steam. The generated SS is heated, and fuel is injected into this air from a fuel injection valve IS to cause combustion, thereby supplementally heating the steam generator □. In this case: (a) Since the main engine exhaust gas and combustion air flow through independent passages, pressure loss in the combustion air passage can be reduced, so the load on the air pump can be eliminated.

(b) The heating amount of the steam generator 3 can be easily controlled by the air flow rate. It has the advantage of

As explained above, this invention has a configuration that includes a combustor that supplementally heats the steam generator depending on the operating conditions in addition to the exhaust heat of the main engine. Since it can be activated, fuel efficiency is improved.

(If) Since the engine operates under efficient operating conditions when the wheels are stopped, the working cost of the engine system is improved (Turf's coefficient of performance is 0.59 power generation efficiency SS), and the noise during operation is extremely low.

You can get 5 benefits.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a conventional combined engine system, FIG. 2 is a block diagram of a combined engine system showing an embodiment of the present invention, and FIG. 3 is a diagram showing an example of the control circuit shown in FIG. Fourth
The figure is a configuration diagram of main parts showing another embodiment of the present invention. In the figure, 1 is the main engine, 2 is the exhaust pipe, 3 is the steam generator,
4 is an expander, S is a capacitor, 6 is a liquid supply pump,
* is the compressor, ■ is the generator, and 12 is the combustion amount. Figure 1

Claims (1)

[Claims] In a combined engine system comprising a steam generator, an expander, a ':1 pump, and a liquid supply pump, and having a Rankine engine as an auxiliary engine operated by exhaust heat of the main engine, the steam generator is auxiliary heated. A composite engine system characterized by the provision of a combustor.