Inlet air preheating system of methanol engine, methanol engine and vehicle

Abstract

The utility model discloses an intake preheating system of a methanol engine, the methanol engine and a vehicle, the intake preheating system comprises a methanol heater and an intake pipe, and a heated air outlet of the methanol heater is connected with an air inlet of the intake pipe through a heater throttle valve; an air outlet of the air filter is connected with an air inlet of the air inlet pipe through a throttle valve; according to the utility model, when the engine is in cold start, hot air heated by the heater is continuously input and directly enters the air inlet header pipe of the engine, so that the temperature after the hot air is mixed with fresh inlet air is increased, the air participating in ignition is hot air, and the success of low-temperature start of the methanol engine is further realized.

Description

Technical Field

[0001] The utility model belongs to the technical field of methanol engine intake systems, and in particular relates to an intake preheating system of a methanol engine, a methanol engine and a vehicle. Background Art

[0002] The statements herein merely provide background art related to the present invention and do not necessarily constitute prior art.

[0003] With the increasing requirements for environmental protection and the rising cost of gasoline and diesel, methanol engines, as a new type of green fuel machine, have obvious advantages and are increasingly valued and promoted on a large scale.

[0004] However, due to the extremely low saturated vapor pressure of methanol at low temperatures, evaporation is slow, and the concentration of the mixed gas is too low to reach the ignition limit. Generally speaking, when the ambient temperature is lower than 16°C, the methanol engine cannot be ignited and started, and an auxiliary cold start device needs to be added to solve its low-temperature starting performance. The current common method is to preheat the coolant inside the engine in advance to create a high-temperature environment inside, which is conducive to engine starting.

[0005] Currently, there are two heating modes: preheating the cooling water in the engine cylinder and preheating the air entering the intake pipe. The water boiler can heat the antifreeze and air. Figure 1 As shown in FIG. 1 , a water boiler 1 is commonly used for heating diesel engines. The water circuit can be heated alone (second branch 8), or the air intake can be heated at the same time (first branch 7). For gas engines or methanol engines, a throttle valve 9 for controlling the mixed gas is provided on the intake pipe. Figure 2 As shown, before the engine is started, the throttle 9 is in a closed state and can only heat a small amount of air in front of the throttle. Moreover, the heated air cannot enter the cylinder before the engine is started, and the amount of hot air entering the intake pipe 2 during the startup process cannot be controlled; a small amount of heated air is far from the large amount of hot air required for ignition, and the effect is extremely limited; preheating water can only indirectly heat the engine cylinder liner. First, the water temperature is transferred to the cylinder liner, and then the cylinder liner transfers it to the air in the cylinder through the wall. According to the principle of heat transfer, temperature difference and time affect the heat transfer effect. Due to the short time of ignition, the heat transfer to the large amount of cold air entering is very limited, and the temperature difference between the wall and the cold air is limited, the heating effect is relatively poor, and the heating time is long, which seriously affects fuel consumption. Utility Model Content

[0006] The utility model aims to provide an intake air preheating system for a methanol engine, which can realize that when the engine is cold started, hot air heated by a heater is continuously input directly into the engine intake manifold, thereby increasing the temperature after mixing with fresh intake air, so that the air involved in ignition is hot air, thereby achieving successful low-temperature starting of the methanol engine.

[0007] In order to achieve the above purpose, the utility model is implemented through the following technical solutions:

[0008] In a first aspect, an embodiment of the utility model provides an intake air preheating system for a methanol engine, comprising a methanol heater and an intake pipe, wherein the heated air outlet of the methanol heater is connected to the air inlet of the intake pipe through a heater throttle;

[0009] It also includes an air filter, the air outlet of which is connected to the air inlet of the intake pipe through a throttle valve.

[0010] As a further technical solution, the hot water outlet of the methanol heater is connected to the water inlet of the engine, and the hot water passes through the engine body and the cylinder head water cavity and is discharged from the water outlet of the engine.

[0011] As a further technical solution, the water outlet of the engine is connected to the water inlet of the methanol heater through a pipeline.

[0012] As a further technical solution, a temperature sensor is provided on the air intake pipe.

[0013] As a further technical solution, the temperature sensor and the heater throttle are electrically connected to the ECU respectively.

[0014] As a further technical solution, before the methanol engine is started, the heater throttle is in a fully open state.

[0015] As a further technical solution, after the methanol engine is successfully ignited and stabilized, the heater throttle and the methanol heater are synchronously closed and shut down.

[0016] As a further technical solution, the heater throttle and the throttle have the same structure, and both adopt an electro-hydraulic throttle, a linear electromagnet throttle, a stepper motor throttle or a DC servo motor throttle.

[0017] In a second aspect, an embodiment of the utility model provides a methanol engine, comprising the intake air preheating system described in the first aspect, wherein an intake pipe of the intake air preheating system is connected to the interior of a cylinder of the engine.

[0018] In a third aspect, an embodiment of the present utility model provides a vehicle, comprising the methanol engine described in the second aspect, wherein the methanol engine is mounted on a vehicle body.

[0019] The beneficial effects of the above-mentioned embodiments of the utility model are as follows:

[0020] The intake preheating system of the methanol engine provided by the utility model can realize the continuous entry of hot air into the cylinder and increase the temperature in the cylinder by connecting the heated air after the throttle. Not only can the intake pipeline be preheated before the engine is started, but hot air can also be continuously provided during the startup process to increase the intake temperature, which is conducive to smooth cold start. The heated hot air is directly introduced into the intake pipeline, eliminating the process of indirectly heating the engine body and heat transfer after water heating. The heating effect is good, the temperature rises quickly, it is conducive to ignition, and the low-temperature start time is greatly shortened.

[0021] The utility model provides an intake air preheating system for a methanol engine, wherein a heater throttle is added between a methanol heater and an intake pipe, and the opening of the throttle is controlled by the temperature in the intake pipe to achieve control of the hot air flow.

[0022] The utility model provides an intake air preheating system for a methanol engine, which heats the air in front of a throttle valve before starting the methanol engine to increase the temperature in an intake pipe; when the methanol engine is cold started, hot air heated by a methanol heater is continuously input directly into an engine intake manifold to increase the temperature after mixing with fresh intake air, so that the air involved in ignition is hot air, thereby achieving successful low-temperature starting of the methanol engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention.

[0024] Figure 1 It is the heating system of the existing diesel engine;

[0025] Figure 2 It is the heating system of the existing methanol engine;

[0026] Figure 3 The utility model relates to a heating system of an intake air preheating system of a methanol engine.

[0027] The schematic diagram is for illustrative purposes only;

[0028] Among them, 1. water boiler; 2. intake pipe; 3. inside of the cylinder; 4. engine water inlet; 5. engine body and cylinder head water cavity; 6. engine water outlet; 7. first branch; 8. second branch; 9. throttle; 10. air filter; 11. methanol heater; 12. heater throttle; 13. temperature sensor. DETAILED DESCRIPTION

[0029] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0030] Explanation of relevant terms:

[0031] Methanol engine: Similar to a gas engine, it is a spark-ignition engine that uses methanol as fuel.

[0032] Methanol heater: Similar to diesel heater, it uses methanol as fuel, burns by ignition, and uses the heat energy of combustion to heat the water or air in the water jacket to output hot water or hot gas.

[0033] Example 1

[0034] The preheating method of the methanol engine mentioned in the background technology has the following disadvantages:

[0035] 1. Preheating water can only heat the engine cylinder liner indirectly. First, the water temperature is transferred to the cylinder liner, and then the cylinder liner transfers it to the air in the cylinder through the wall. According to the principle of heat transfer, temperature difference and time affect the heat transfer effect. However, due to the short time of ignition, the heat transfer to the large amount of cold air entering is very limited. In addition, the temperature difference between the wall and the cold air is limited, the heating effect is relatively poor, and the heating time is long, which seriously affects fuel consumption.

[0036] 2. Before the engine is started, the throttle valve of the engine intake pipe is in a closed state. It can only heat a small amount of air in front of the throttle valve, which is far from the large amount of hot air required for ignition, and the effect is extremely limited.

[0037] 3. During the startup process, the amount of hot air entering the intake pipe cannot be controlled.

[0038] In order to solve the above technical problems, in a typical implementation of the present utility model, as Figure 3 As shown, an intake air preheating system for a methanol engine is provided, comprising a methanol heater 11 and an intake pipe 2, wherein the heated air outlet of the methanol heater 11 is connected to the air inlet of the intake pipe 2 through a heater throttle 12;

[0039] It also includes an air filter 10 , an air outlet of the air filter 10 is connected to the air inlet of the intake pipe 2 through a throttle valve 9 .

[0040] The air intake preheating system provided by the utility model connects the hot air heated by the methanol heater 11 to the heater throttle 12, so that the hot air continues to enter the cylinder; a heater throttle 12 is added to the preheating control branch, and the opening of the heater throttle 12 is controlled by the temperature in the intake pipe, so that the amount of hot air can be controlled.

[0041] Furthermore, the hot water outlet of the methanol heater 11 is connected to the engine water inlet 4 , and the hot water passes through the engine body and the cylinder head water cavity 5 and is discharged from the engine water outlet 6 .

[0042] Furthermore, the engine water outlet 6 is connected to the water inlet of the methanol heater 11 through a pipeline, and the cooled water returns to the methanol heater 11 to be heated again and reused.

[0043] In this embodiment, a temperature sensor 13 is provided on the intake pipe 2. The temperature sensor 13 and the heater throttle 12 are electrically connected to the ECU respectively. The ECU is an electronic control unit on the vehicle. The ECU obtains the temperature of the intake pipe 2 in real time through the temperature sensor 13, and adjusts the opening of the heater throttle according to the temperature of the intake pipe 2 to achieve control of the hot air flow.

[0044] In this embodiment, before the methanol engine is started, the heater throttle 12 is in a fully open state, which can quickly increase the temperature in the cylinder.

[0045] In this embodiment, after the methanol engine is successfully ignited and stabilized, the heater throttle and the methanol heater are synchronously closed and shut down.

[0046] In this embodiment, the heater throttle 12 and the throttle 9 have the same structure and both adopt existing structures, and can adopt an electro-hydraulic throttle, a linear electromagnet throttle, a stepper motor throttle or a DC servo motor throttle.

[0047] In this embodiment, the methanol heater adopts a water boiler heating method.

[0048] The intake preheating system of the methanol engine provided in this embodiment connects the heated air after the throttle 9, so that the hot air can continuously enter the cylinder and increase the temperature in the cylinder. Not only is the intake line preheated before the engine starts, but hot air can also continue to be provided during the startup process to increase the intake temperature, which is conducive to a smooth cold start. The heated hot air is directly introduced into the intake duct, eliminating the process of indirectly heating the engine body and heat transfer after water heating. The heating effect is good, the temperature rises quickly, it is conducive to ignition, and the low-temperature start time is greatly shortened; a heater throttle 12 is added between the heater and the intake pipe, and the opening of the heater throttle 12 is controlled by the temperature in the intake pipe to achieve control of the hot air flow.

[0049] Its main control strategies are as follows:

[0050] 1) In a low-temperature environment, before the engine is started, the heater throttle is fully open to quickly increase the temperature in the cylinder; when heated to the preset temperature T, the opening is gradually reduced to keep the temperature at a constant temperature;

[0051] 2) When the engine starts to ignite, fresh cold air enters the intake duct, the temperature inside the intake duct drops below T, and the heater throttle continues to open, thereby increasing the temperature inside the intake duct;

[0052] 3) After the engine is successfully ignited and stabilized for 3 seconds, the heater throttle and the heater are closed and shut down synchronously.

[0053] In summary, the utility model introduces hot air after the throttle valve and controls the intake air temperature through the heater throttle valve, thereby avoiding the problem of poor heat transfer effect caused by indirect heat transfer through preheating water, and also avoiding the disadvantage of heating only a small amount of air before the throttle valve. By directly heating the intake air, the intake air temperature is quickly increased, the heating efficiency is improved, the starting time is shortened, and a high-temperature environment is directly provided, making the low-temperature cold start of the methanol engine more time-saving and efficient, and can be promoted and used in batches.

[0054] Example 2

[0055] In a typical embodiment of the present invention, a methanol engine is provided, comprising the intake air preheating system described in Example 1, wherein an intake pipe of the intake air preheating system is connected to the inside 3 of a cylinder of the engine.

[0056] Example 3

[0057] In a typical implementation of the present invention, a vehicle is provided, comprising the methanol engine described in Example 2, wherein the methanol engine is mounted on a vehicle body.

[0058] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. An intake air preheating system for a methanol engine, characterized in that: It includes a methanol heater and an intake pipe, wherein the heated air outlet of the methanol heater is connected to the air inlet of the intake pipe through a heater throttle; It also includes an air filter, the air outlet of which is connected to the air inlet of the intake pipe through a throttle valve.

2. The intake air preheating system of the methanol engine according to claim 1, characterized in that: The hot water outlet of the methanol heater is connected to the water inlet of the engine, and the hot water passes through the engine body and the cylinder head water cavity and is discharged from the water outlet of the engine.

3. The intake air preheating system of the methanol engine according to claim 2, characterized in that: The water outlet of the engine is connected to the water inlet of the methanol heater through a pipeline.

4. The intake air preheating system of the methanol engine according to claim 1, characterized in that: A temperature sensor is arranged on the air intake pipe.

5. The intake air preheating system of the methanol engine according to claim 4, characterized in that: The temperature sensor and the heater throttle are electrically connected to the ECU respectively.

6. The intake air preheating system of the methanol engine according to claim 1, characterized in that: Before the methanol engine is started, the heater throttle is in full open position.

7. The intake air preheating system of a methanol engine as claimed in claim 1, characterized in that: After the methanol engine is successfully ignited and stabilized, the heater throttle and the methanol heater are synchronously closed and shut down.

8. The intake air preheating system of a methanol engine as claimed in claim 1, characterized in that: The heater throttle and the throttle have the same structure, and both adopt an electro-hydraulic throttle, a linear electromagnet throttle, a stepper motor throttle or a DC servo motor throttle.

9. A methanol engine, characterized in that: It comprises the intake air preheating system according to any one of claims 1 to 8, wherein the intake pipe of the intake air preheating system is connected to the inside of the cylinder of the engine.

10. A vehicle, characterized in that: It comprises the methanol engine as claimed in claim 9, wherein the methanol engine is mounted on a vehicle body.

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