JPH01110831A - Turbocompound engine - Google Patents

Abstract

PURPOSE:To properly achieve the proper exhaust gas flow rate and energy recovery by forming a combustion chamber wall into a heat shielding structure and installing the turbine of a turbocharger generator into an exhaust pipe and constituting a turbine nozzle into a variable mechanism. CONSTITUTION:An exhaust passage is formed into a perfect heat shielding structure by forming a combustion chamber wall 15, heat insulating liner 23, cylinder liner 8, piston head 31, exhaust port linear 30, and an exhaust manifold 5 from ceramic material, and all the exhaust energy can be recovered by a turbocharger generator 25 on the downstream side. An AC machine 3 is operated as dynamo in a part having a low engine load, and the exhaust energy is accumulated into a battery, while, in a part having a large engine load, a compressor 2 is driven to act as turbocharger, and a part is supplied as the electric power energy by power generation. Further, a turbine 4 varies the nozzle area by revolving a nozzle 32, and the nozzle area can be varied, and the exhaust flow rate and the most suitable energy recovery can be contrived.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a turbo compound engine equipped with a turbocharger generator for automobiles and the like. The turbocharger generator referred to herein has a turbine and a compressor, and an alternating current machine is provided between both blades, and has the functions of a turbocharger and a generator/electric motor.

[Conventional technology]

Conventionally, a turbocharging system for an internal combustion engine that enables adequate and sufficient intake air supercharging over a wide range from low speeds to high speeds is disclosed in, for example, Japanese Patent Laid-Open No. 195329/1983. In a turbocharger for an internal combustion engine, the scroll of the turbine of the turbocharger communicates with the exhaust manifold that communicates with the exhaust boat of the internal combustion engine, and the fuel injection pump installed in the main body of the internal combustion engine has a fuel injection circuit that handles the load. The compressor is equipped with a load sensor that detects the energy of the exhaust gas of the internal combustion engine, and is composed of a turbine driven by the energy of the exhaust gas of the internal combustion engine, and a compressor that supercharges intake air into the cylinder by the drive of the turbine. The motor/generator is operated as a motor or a generator depending on the operating state of the internal combustion engine, and more specifically, the motor/generator is operated at least at low and high speeds of the internal combustion engine. In the load operating range, it is driven as an electric motor.

(Problems to be Solved by the Invention) However, during turbocharging of the conventional internal combustion engine as described above, the scroll of the turbine of the turbocharger communicates with the exhaust manifold that communicates with the exhaust port of the internal combustion engine. However, it does not disclose how to effectively recover the exhaust energy contained in exhaust gas by considering the insulation structure of the exhaust pipe and the engine itself, and it does not disclose how to optimize the exhaust gas flow rate and energy recovery. It's not something I did.

The purpose of this invention is to solve the above problems, and to prevent the exhaust energy of exhaust gas from flowing out through the combustion chamber wall of the engine and the exhaust pipe of the exhaust boat, exhaust manifold, etc. Use a large-capacity alternator that can generate high output, configure it to recover most of the effective energy, and use the recovered energy effectively, for example, to ensure sufficient power generation during idling. It is an object of the present invention to provide a turbo compound engine in which a turbine nozzle is configured as a variable mechanism so that exhaust gas flow rate and energy recovery are optimized even though it is a single turbine.

[Means for solving problems]

In order to solve the above problems and achieve the above objects, the present invention is configured as follows.

That is, the present invention is characterized in that the combustion chamber wall of the engine is constructed with a heat insulating structure using a ceramic material or the like, a turbine nozzle of a turbocharger generator is provided in the exhaust pipe of the engine, and the turbine nozzle of the turbine is constructed as a variable mechanism. This article relates to a turbo compound engine.

[Effect]

The turbo compound engine according to the present invention is constructed as described above and operates as follows. That is, since the combustion chamber wall of the engine is configured to have an adiabatic structure and the turbine of the turbocharger generator is attached to the exhaust pipe,
It is possible to send all the exhaust energy contained in the exhaust gas from the engine to the turbocharger generator, which is an energy recovery device installed downstream, without letting it flow out from the cylinder head, etc. Also, since the turbine nozzle is configured with a variable mechanism, it can be used during idling, etc. When the flow rate of exhaust gas is low, the nozzle area of the turbine nozzle is reduced,
Even though the flow rate of exhaust gas is small, the flow rate of exhaust gas is increased to rotate the turbine blades quickly, ensuring sufficient power generation performance of the alternator, and even though it is a single turbine, the flow rate of exhaust gas is increased. Optimization with energy recovery can be achieved.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a turbo compound engine according to the present invention will be described in detail below with reference to the drawings. FIG. 1 is a schematic sectional view showing an embodiment of a turbo compound engine according to the present invention, FIG. 2 is a schematic sectional view showing an example of the turbocharger generator shown in FIG. 1, and FIG. 3 is a schematic sectional view showing an example of the turbocharger generator shown in FIG. 2. The sectional view and FIG. 4 are explanatory diagrams showing the turbine nozzle of the turbine of FIG. 2.

In FIG. 1, a turbo compound engine comprising a turbocharger generator 25 and an adiabatic engine 1, which is an embodiment of the present invention, is indicated generally by the reference numeral 10. The turbocharger generator 25 has a second
As shown in the figure, it mainly consists of a turbine 4 driven by exhaust gas from an adiabatic engine 1, a compressor 2 supercharging by the drive of the turbine 4, and an alternating current machine 3 driven by the turbine 4. Regarding turbine 4,
Turbine blades 22 are disposed within the turbine housing 18, and as shown in FIG. 3 or 4, the turbine nozzle 32 is configured as a variable mechanism so that the nozzle area can be changed by rotation of a rotating shaft 33. It is. Further, regarding the compressor 2, a compressor impeller 21 is disposed within a compressor housing 17. Further, a compressor impeller 21 and a turbine blade 22 are fixed to both ends of the shaft 20.

Regarding AC machine 3, the above-mentioned Japanese Patent Application Laid-Open No. 60-1953
Similar to the turbocharger for an internal combustion engine disclosed in Publication No. 29, etc., it can function as an electric motor/generator.

The alternating current machine 3 includes a magnet rotor 27, which is a permanent magnet extending in the axial direction, attached to the center of a shaft 20 that passes through the center housing 16, a stator coil 26, and the like. The shaft 20 is rotatably supported by a bearing 19 fixed to the center housing 16. Although not shown, the bearing 19 is located at the turbine 4.
Of course, it is possible to construct a structure in which they are supported as a pair only between the AC generator 3 and the AC generator 3.

The turbine blades 22 are rotated by the flow of exhaust gas sent to the turbine scroll 28, that is, the exhaust gas energy, and the exhaust gas flows in the direction of arrow C. In addition, the compressor impeller 21 has the function of introducing air from an intake port as shown by arrow A, and sending the air as intake air to the intake manifold 11 of the adiabatic engine 1 through the air passage 29.

The alternating current machine 3 is driven by the turbine 4 and has the function of inducing a current in the stator coil 26 and returning this current to the power supply side, that is, the regenerative current can be used to charge a battery or as a load. be.

In the adiabatic engine 1 in the turbo compound engine 10 according to the present invention, the combustion chamber wall 15 of the cylinder head 12 constituting the combustion chamber 13 of the engine is formed of a ceramic material such as silicon nitride or silicon carbide, and Potassium titanate whiskers in between,
A heat insulating structure is constructed by interposing a heat insulating material 23 made of a ceramic material such as alumina fiber. Furthermore, a cylinder liner 8 made of a ceramic material or the like can also be fitted into the cylinder body 7. Further, the piston 9 has a heat-insulating structure, and the piston hend 31 is made of a similar ceramic material and is fixed to the piston skirt via a heat-insulating material. Further, each cylinder head 12 of the adiabatic engine 1 communicates with the exhaust manifold 5 and then with the turbine scroll 28 via each exhaust port 6. The exhaust port liner 30 constituting the exhaust port 6 has a heat insulating structure made of a ceramic material, a heat insulating material, or the like. In addition, the exhaust port 6 has
Similarly, an exhaust manifold 5 having a heat insulating structure made of ceramic material or the like is connected to the exhaust manifold 5. The exhaust gas from the exhaust manifold 5 is then sent to the turbine 4. With this configuration, the turbine 4 is connected from the cylinder head 12 of the adiabatic engine 1.
The exhaust passageway up to the exhaust pipe, that is, the exhaust pipe can be configured to have a completely insulated structure. With this configuration, it is possible to prevent the exhaust energy of the exhaust gas exhausted from the adiabatic engine 1 from flowing out through the cylinder head, intermediate path, etc.
All of the exhaust energy can be recovered by an energy recovery device, ie, a turbocharger generator, installed downstream. Further, each intake manifold 11 is provided with a fuel injection nozzle in the case of a diesel engine, and fuel is controlled and sent to the fuel injection nozzle by a fuel pump and a controller that controls them. It is composed of In addition, in the figure, 14 indicates an intake port, and 24 indicates an exhaust pulp.

The turbo compound engine 10 according to the present invention is configured as described above, and is particularly characterized by the following operation points. turbocharger generator 25
The AC a3 used here has a large capacity so that it can generate a large output.

By configuring the alternator 3 to have a large capacity, for example, in areas where the engine load is small, there is no need to send a large amount of intake air to the engine, so the conventional function during turbocharging is no longer necessary, so the adiabatic engine l The rotational energy generated by the exhaust energy of the exhaust gas is converted into electric power by the AC machine 3 and used as regenerative current to store electricity in a battery or as another load. However, in areas where the engine load is large, the engine requires a large amount of intake air, so a part of the rotational energy generated by the exhaust energy of the exhaust gas of the adiabatic engine 1 is used to function as a turbocharger. The rotational energy is consumed as driving energy, and the remaining part of the rotational energy is operated to supply the electric power generated by the alternating current machine 3 as electric energy. Further, the turbine 4 of the turbocharger generator 25 is configured in a single row without having multiple stages. This is because if the ribs are configured in multiple stages, the exhaust pressure applied to the turbine will increase the exhaust stroke pressure of the diesel cycle, resulting in a problem of lowering the overall efficiency of the engine. Therefore, the turbines 4 are arranged in a row to increase the expansion ratio of the exhaust gas and to minimize the friction of the bearings 19, etc., thereby increasing the maximum efficiency. Furthermore, the output of the turbocharger generator 25 is secured to a boost pressure that matches the fuel flow rate of the adiabatic engine 1, and the remaining output is converted into electric power output to recover all the effective energy of the exhaust gas. In addition, energy recovery by a single turbine 4 is
Since it is difficult to optimize the flow rate of the exhaust gas, the turbine nozzle 32 is configured with a variable mechanism so that the nozzle area can be changed by rotating the rotating shaft 33, and the turbine speed and the speed of the gas flowing out from the turbine nozzle 32 are optimized. This is what we decided to do.

(Effects of the Invention) Since the turbo compound engine according to the present invention is configured as described above, it exhibits the following unique effects. That is, in the present invention, the combustion chamber wall of the engine is configured to have a heat-insulating structure, the turbine of the turbocharger generator is attached to the exhaust pipe, and the turbine nozzle is configured with a variable mechanism, so that the exhaust energy of the exhaust gas of the engine is reduced. All of the energy can be sent to the turbine of the turbocharger generator, which is an energy recovery device installed downstream, and the energy can be recovered in a way that matches the exhaust gas flow rate.For example, when the exhaust gas flow rate is low, such as during idling, the turbine nozzle By narrowing the nozzle area and increasing the flow rate of exhaust gas even though the flow rate of exhaust gas is small, the turbine blades rotate faster, ensuring sufficient power generation performance of the alternator even though it is a single turbine. Thus, the flow rate of exhaust gas from the engine and the energy recovery in the turbocharger generator can be optimized. Furthermore, the alternating current machine of the turbocharger generator can be constructed with a large capacity, and exhaust energy can be consumed effectively. That is, when the load is small, the rotational energy generated by the exhaust gas is converted into electric power, and when the load is large, the driving energy and electric power energy for the compressor can be supplied. Further, by arranging the turbines in a row to increase the expansion ratio of exhaust gas, the overall efficiency of the engine can be improved. Furthermore, if the turbocharger generator output is maintained at a boost pressure that matches the fuel flow rate of the adiabatic engine, and the remaining output is converted to electric power output without consuming any more for intake air supply, the exhaust gas will be reduced. All available energy can be recovered.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view showing an embodiment of the turbo compound engine according to the present invention, FIG. 2 is a schematic sectional view showing an example of the turbocharger generator shown in FIG. 3, and FIG. 3 is a schematic sectional view showing the turbine shown in FIG. The sectional view and FIG. 4 are explanatory diagrams showing the turbine nozzle of the turbine of FIG. 2. 1-----Adiabatic engine, 2---Compressor, 3---AC machine, 4---Turbine, 5---Exhaust manifold, 6...
-Exhaust boat, 8-... Cylinder liner, 9-...
---Piston, lO---turbo compound engine, 12--- cylinder head, 13--
・・Combustion chamber, 15−・・・・−・Combustion chamber wall, 20・・−
・-Shaft, 22-...Turbine blade,
23---Insulation material, 25---Turbocharger generator, 30---Exhaust boat liner,
31-- Piston head, 32-- Turbine nozzle, 33-- Rotating shaft. Patent Applicant Isuri Motors Co., Ltd. Agent Patent Attorney Sodai Onaka 1 Figure 2

Claims (1)

[Claims] A turbo compound engine characterized in that a combustion chamber wall of the engine is constructed with a heat insulating structure using a ceramic material or the like, a turbine of a turbocharger generator is attached to an exhaust pipe of the engine, and a turbine nozzle is constructed as a variable mechanism.