A closed-loop steam energy-saving driving device and method based on exhaust heat of an internal combustion engine

Abstract

The application discloses a kind of closed loop steam energy-saving driving device and method based on internal combustion engine exhaust waste heat, belong to internal combustion engine waste heat recovery energy-saving technical field.Device includes internal combustion engine main body, exhaust waste heat recovery unit, full closed loop steam circulation unit, coaxial power output unit, heat dissipation-condensation collaborative unit and intelligent control unit;Internal combustion engine exhaust pipe penetrates waste heat evaporator, waste heat evaporator, steam turbine, condenser, liquid storage tank, working medium circulating pump form full closed steam circulation loop, at least one power output module is connected in series on the coaxial transmission shaft of steam turbine, power output module is any one or multiple combinations in generator, heat dissipation fan driving module, auxiliary power coupling module, condenser and internal combustion engine radiator are integrally arranged, and synchronous heat dissipation is carried out by the same fan.The present application can realize the flexible adaptation of single function / multi-function of waste heat recovery, completely eliminate engine parasitic load, improve internal combustion engine thermal efficiency 4%-12%, full scene adaptability is strong, and protection range has no dead angle.

Description

Technical Field

[0001] This invention relates to the field of waste heat recovery and utilization technology of internal combustion engines, specifically to a closed-loop steam energy-saving drive device and method based on the waste heat of internal combustion engine exhaust, applicable to various internal combustion engine power equipment such as automotive internal combustion engines, construction machinery internal combustion engines, marine internal combustion engines, and stationary internal combustion engine generator sets. Background Technology

[0002] As the core power equipment in current transportation, construction machinery and stationary power generation, the internal combustion engine has always had a low thermal efficiency. The rated thermal efficiency of conventional gasoline engines is only 25%-35%, and that of diesel engines is 35%-45%. The remaining 55%-75% of fuel energy is directly lost to the environment in the form of exhaust waste heat, cylinder liner heat dissipation waste heat, etc. Among them, exhaust waste heat accounts for 30%-40% of the total fuel energy, which is a high-quality recyclable energy source with great energy-saving potential.

[0003] Existing internal combustion engine waste heat recovery technologies are mainly divided into three categories: The first category is turbine-compound technology, which can only provide auxiliary power by directly coupling the engine crankshaft through the exhaust turbine. It cannot achieve waste heat power generation and cooling fan drive, has a single function, and can only recover exhaust pulse kinetic energy. Under low load conditions, it will increase exhaust back pressure, which will increase fuel consumption. The second category is single ORC waste heat power generation technology, which can only generate electricity by heating the working fluid with exhaust waste heat. The system has its own independent condenser and dedicated condenser fan. More than 30% of the recovered electricity is offset by the power consumption of the condenser fan, which greatly reduces the energy-saving benefits. It cannot drive the cooling fan or auxiliary power output. The third category is scattered waste heat-driven fan technology, which is mostly an open-loop design without a closed-loop working fluid circuit. It cannot achieve power generation and auxiliary power output, and has extremely poor adaptability to operating conditions.

[0004] Meanwhile, existing patents for related technologies offer fragmented protection for single functions, covering only specific solutions and failing to achieve comprehensive coverage across all scenarios, whether single or multi-functional combinations. Competitors can easily circumvent these patents by removing functions or adjusting the structure, resulting in ineffective protection. Furthermore, existing solutions require targeted development for specific application scenarios, making them unsuitable for all scenarios, including passenger cars, commercial vehicles, construction machinery, and ships, exhibiting extremely poor versatility. To address these shortcomings, there is an urgent need for a comprehensive, energy-efficient, and scenario-compatible internal combustion engine waste heat recovery solution, while simultaneously resolving the issues of easy patent circumvention and narrow protection scope in existing technologies. Summary of the Invention

[0005] 1. Purpose of the invention The purpose of this invention is to overcome the aforementioned deficiencies in the prior art and provide a closed-loop steam energy-saving drive device and method based on the waste heat of internal combustion engine exhaust. Through a fully closed-loop steam circulation system, it achieves full-scenario adaptability of "independent operation of single functions, operation of any two functions in combination, and operation of three functions simultaneously", completely eliminating the engine parasitic load of the cooling system, efficiently recovering exhaust waste heat, and significantly improving the overall thermal efficiency of the internal combustion engine. At the same time, through a comprehensive patent layout, it achieves all-round protection of the combination of functions, completely eliminating the circumvention design of competitors and forming a track-level patent barrier. 2. Technical Solution

[0006] To achieve the above-mentioned objectives, the technical solution of the present invention is as follows: A closed-loop steam energy-saving drive device based on the exhaust waste heat of an internal combustion engine, comprising an internal combustion engine body, an exhaust waste heat recovery unit, a fully closed-loop steam circulation unit, a coaxial power output unit, a heat dissipation-condensation coordination unit, a liquid storage and pressure stabilization unit, and an intelligent control unit.

[0007] The exhaust waste heat recovery unit includes a waste heat evaporator and an internal combustion engine exhaust pipe. The internal combustion engine exhaust pipe passes through the internal heat exchange chamber of the waste heat evaporator. The outer wall of the exhaust pipe is fixed with reinforced heat exchange fins. The waste heat evaporator is filled with a closed-loop working fluid. Through indirect heat exchange, the waste heat of the exhaust is efficiently transferred to the working fluid, and more than 85% of the exhaust waste heat can be recovered.

[0008] The fully closed-loop steam circulation unit includes a steam delivery pipe, a steam turbine, a waste steam return pipe, a condenser, a liquid storage tank, a working fluid circulation pump, and a one-way check valve. The steam outlet of the waste heat evaporator is connected to the inlet of the steam turbine through the steam delivery pipe. The outlet of the steam turbine is connected to the inlet of the condenser through the waste steam return pipe. The liquid outlet of the condenser is connected to the inlet of the liquid storage tank through a pipeline. The liquid outlet of the liquid storage tank is connected to the inlet of the waste heat evaporator through the working fluid circulation pump and the one-way check valve, forming a fully closed and leak-free circulation loop. The circulating working fluid only undergoes a gas-liquid phase change within the loop and is not discharged externally. There is no working fluid loss and no need for frequent replenishment.

[0009] The coaxial power output unit includes a coaxial drive shaft and at least one set of independently controllable power output modules. The power output shaft of the steam turbine is fixedly connected to the coaxial drive shaft. The power output modules are installed in series on the coaxial drive shaft. The power output modules are any one or more combinations of generator modules, cooling fan drive modules, and auxiliary power coupling modules. Each set of power output modules is equipped with an independent controllable clutch mechanism, which can independently control the on / off state of the module, realizing single-function independent operation or multi-function synchronous operation. It does not require multiple sets of power mechanisms, has a compact structure, and low mechanical loss.

[0010] The heat dissipation-condensation co-processing unit includes an internal combustion engine radiator, with the condenser fixed to the windward side of the radiator. The cooling fan of the cooling fan drive module is positioned facing both the radiator and the condenser, enabling simultaneous cooling of the radiator and condensation of exhaust vapor in the condenser. This completely eliminates the need for a separate condenser fan in the ORC system, eliminating the need for additional heat dissipation mechanisms, further reducing energy loss, and improving system integration.

[0011] The intelligent control unit includes a detection component and a controller. The detection component includes a temperature sensor, a pressure sensor, a speed sensor, and a liquid level sensor. The signal output terminals of each sensor are electrically connected to the controller. The controller is electrically connected to the working fluid circulation pump and the controllable clutch mechanism of each power output module, respectively, to realize full parameter monitoring and intelligent control of the circulation process.

[0012] Furthermore, the generator module includes a generator rotor and a controllable clutch mechanism. The generator rotor is fixed on a coaxial transmission shaft, and the controllable clutch mechanism is located between the generator rotor and the steam turbine. The generator's output end is connected to the equipment's energy storage battery and the entire machine's electrical load through a voltage stabilizing and rectifying module. It can convert the recovered waste heat into electrical energy to directly supply the vehicle's electrical appliances, and store excess electrical energy in the energy storage battery.

[0013] Furthermore, the cooling fan drive module includes a cooling fan and a controllable clutch mechanism. The driving end of the controllable clutch mechanism is fixedly connected to the coaxial transmission shaft, and the driven end is fixedly connected to the cooling fan. The start and stop of the fan and the speed matching can be controlled through the clutch mechanism.

[0014] Furthermore, the auxiliary power coupling module includes a reduction gear set, a coupling, and a controllable clutch mechanism. The driving end of the controllable clutch mechanism is fixedly connected to the coaxial transmission shaft, and the driven end is connected to the input end of the reduction gear set. The output end of the reduction gear set is coupled to the power output system of the internal combustion engine through the coupling, which can convert the high-speed, low-torque power of the steam turbine into low-speed, high-torque power suitable for the engine, thereby achieving efficient transmission of auxiliary power.

[0015] Furthermore, the internal combustion engine power output system includes the internal combustion engine crankshaft, gearbox input shaft, hydraulic main pump for construction machinery, propulsion shaft system for ships, and generator power end. The auxiliary power coupling mechanism can be coupled with any type of power output system, adapting to all internal combustion engine application scenarios. The equipment energy storage battery and the entire machine's electrical load include vehicle-mounted batteries, construction machinery vehicle-mounted power grids, shipboard electrical systems, and stationary generator auxiliary power systems.

[0016] Furthermore, the waste heat evaporator is a shell-and-tube finned heat exchanger, the internal combustion engine exhaust pipe is the heat exchange tube, the circulating working fluid flows on the shell-and-tube side, and the enhanced heat exchange fins are spiral or straight structures, uniformly welded to the outer wall of the exhaust pipe; the steam turbine is a small radial-flow steam turbine or a vortex expander, adapted to the temperature and pressure fluctuation characteristics of the internal combustion engine exhaust waste heat, and can stably start and output power under low steam pressure; the circulating working fluid is deionized water or a low-boiling-point organic Rankine cycle working fluid, which can be flexibly selected according to the exhaust temperature characteristics of the internal combustion engine.

[0017] Furthermore, the storage tank is equipped with a liquid level sensor and a pressure stabilizing airbag. The liquid level sensor is electrically connected to the controller and can monitor the working fluid level in real time to ensure stable circulation. The pressure stabilizing airbag is used to maintain stable pressure inside the circulation loop, prevent cavitation in the working fluid circulation pump, and improve the stability of system operation.

[0018] The present invention also provides a closed-loop energy-driven method for exhaust waste heat of an internal combustion engine based on the above-mentioned device, comprising the following steps: (1) Waste heat absorption and steam generation stage: The main body of the internal combustion engine starts and runs, and the high-temperature exhaust flows through the exhaust pipe of the internal combustion engine to the waste heat evaporator. The exhaust waste heat is transferred to the circulating working fluid through the enhanced heat exchange fins. The working fluid absorbs heat and vaporizes to form high-pressure steam. The detection component monitors the circulating parameters such as steam temperature, pressure, speed, and liquid level in real time and transmits them to the controller; (2) Power matching and drive control stage: The high-pressure steam enters the steam turbine through the steam delivery pipe, drives the impeller to rotate and converts the internal energy of the steam into mechanical energy, drives the coaxial transmission shaft to rotate, and the controller controls the controllable clutch mechanism of the corresponding power output module to engage / disengage according to the operating conditions of the internal combustion engine, the circulating parameters and the load requirements. Disconnect to achieve single-function independent operation or multi-function synchronous operation; (3) Exhaust steam condensation and closed-loop reflux stage: The exhaust steam after the steam turbine does work enters the condenser through the exhaust steam reflux pipe. Under the cooling effect of the cooling fan, it is condensed into liquid working fluid. After the liquid working fluid flows into the storage tank for stabilization, it is pressurized by the working fluid circulation pump and returned to the waste heat evaporator by the one-way check valve to complete the fully closed loop. The one-way check valve can prevent the working fluid from flowing back and ensure the stable operation of the loop in one direction; (4) Intelligent control stage under all working conditions: The controller receives the monitoring data of the detection component in real time. According to the internal combustion engine water temperature, exhaust temperature, steam pressure and equipment load, it dynamically adjusts the flow rate of the working fluid circulation pump and the clutch state of each power output module to adapt to the stable operation of the internal combustion engine under all working conditions and maximize the energy saving effect.

[0019] Furthermore, in step (2), the single-function independent operation mode includes: Pure power generation mode: The controller only controls the controllable clutch mechanism of the generator module to engage, while the other modules are disconnected. The steam turbine only drives the generator to run, realizing waste heat recovery and power generation, which is suitable for internal combustion engine idling and low load conditions. Pure heat dissipation drive mode: The controller only controls the controllable clutch mechanism of the cooling fan drive module to engage, while the other modules are disengaged. The steam turbine only drives the cooling fan to run, realizing waste heat-driven heat dissipation, which is suitable for high temperature and normal load conditions of internal combustion engines. Pure auxiliary power mode: The controller only controls the engagement of the controllable clutch mechanism of the auxiliary power coupling module, while the other modules are disconnected. The steam turbine only provides auxiliary power to the internal combustion engine power output system, which is suitable for high-speed and heavy-load operating conditions of the internal combustion engine.

[0020] Furthermore, in step (2), the multi-functional synchronous operation mode includes the combined operation of any two functions and the synchronous operation of three functions. The controller adjusts the output power distribution of each module according to the load demand to achieve optimal energy utilization. 3. Beneficial effects

[0021] (1) Full-function coverage without blind spots, and maximum patent protection: Through the top-level general core architecture design, this invention includes all solutions of "single function, any two function combinations, and all three functions" into the core protection scope. No matter which combination of waste heat power generation, waste heat driven fan, or auxiliary power output the competitor adopts, as long as the "full closed-loop steam circulation + coaxial power output + heat dissipation-condensation synergy" core architecture of this invention is adopted, it will fall into the patent protection scope. This completely eliminates the design of circumventing by deleting structures and forms a track-level patent barrier. The protection scope is far greater than that of existing fragmented patents.

[0022] (2) Universal compatibility across all scenarios, no need to modify the engine body: The entire system of the present invention only requires the addition of a waste heat evaporator to the engine exhaust pipe. All other components can be flexibly arranged externally without any modification to the core structure of the internal combustion engine body, crankshaft, cylinder, etc. It can be directly adapted and installed for gasoline / diesel engines, passenger cars / commercial vehicles, excavators and other construction machinery, ships, and stationary generator sets. The universal scope covers almost all internal combustion engine application scenarios, solving the defect that the existing technology can only be adapted to specific models.

[0023] (3) Coordinated heat dissipation and condensation depth to completely eliminate redundant energy consumption: The present invention directly attaches and fixes the ORC condenser to the windward side of the engine radiator, and uses the same waste heat-driven cooling fan to simultaneously realize engine heat dissipation and ORC exhaust steam condensation. This completely eliminates the independent condensing fan of the existing ORC system and also completely eliminates the power consumption of the cooling fan on the engine. It is equivalent to saving the energy consumption of two cooling systems at the same time, which fundamentally solves the industry pain point of "recovered energy being offset by additional heat dissipation power consumption" in the existing ORC system, and improves energy saving benefits by more than 30%.

[0024] (4) Multi-mode intelligent control, positive energy saving benefits under all working conditions: This invention achieves flexible switching between single function and multi-function through an independently controllable clutch mechanism, solving the defects of negative benefits under low load in existing turbo composite technology and poor adaptability of existing ORC technology: Under low load idling conditions, it can switch to pure power generation mode, and the recovered electrical energy completely covers the system's own power consumption, achieving positive benefits; under normal working conditions, it can switch to power generation + heat dissipation mode, completely eliminating the parasitic load on the engine; under high load conditions, it can achieve simultaneous operation of three functions, maximizing the energy saving effect, with no negative benefit scenarios in the entire working condition range, and the measured comprehensive fuel saving rate can reach 8%-18%, which is far higher than the fuel saving upper limit of 3%-6% of existing mass-produced technologies.

[0025] (5) Fully closed-loop circulation, no working fluid loss, and stable operation: A fully closed, leak-free circulation loop is adopted. The circulating working fluid undergoes a gas-liquid phase change only within the loop, with no external emissions, no leakage, and no need for frequent replenishment. This solves the problems of high working fluid loss, high maintenance costs, and poor circulation stability associated with open-loop circulation, and can meet the long-term stable operation requirements of equipment such as vehicles, construction machinery, and ships. (See attached diagram for details.) Figure 1 is a schematic diagram of the overall structure of the device described in this invention (three-function full configuration version, abstract figure); Figure 2 is a simplified schematic diagram of the pure power generation mode of this invention; Figure 3 is a simplified schematic diagram of the pure heat dissipation drive mode of this invention; Figure 4 is a simplified schematic diagram of the pure auxiliary power mode of this invention; Figure 5 is an electrical connection block diagram of the intelligent control unit of this invention; Figure 6 is a block diagram of the closed-loop steam cycle and energy flow of this invention.

[0026] The corresponding names in the attached diagram are as follows: 1 - Internal combustion engine body, 2 - Internal combustion engine exhaust pipe, 3 - Enhanced heat exchange fins, 4 - Waste heat evaporator, 5 - Steam delivery pipe, 6 - Steam turbine, 7 - Coaxial drive shaft, 8 - Generator module, 9 - First controllable clutch mechanism, 10 - Cooling fan drive module, 11 - Second controllable clutch mechanism, 12 - Auxiliary power coupling module, 13 - Third controllable clutch mechanism, 14 - Exhaust steam return pipe, 15 - Condenser, 16 - Internal combustion engine radiator, 17 - Liquid storage tank, 18 - Pressure stabilizing airbag, 19 - Working fluid circulation pump, 20 - One-way check valve, 21 - Detection component, 22 - Controller, 23 - Voltage stabilizing and rectifying module, 24 - Equipment energy storage battery, 25 - Reduction gear set, 26 - Coupling, 27 - Internal combustion engine power output system. Detailed Implementation

[0027] The present invention will be further described in detail below with reference to specific embodiments and accompanying drawings, but the scope of protection of the present invention is not limited to the following embodiments. Example 1

[0028] This embodiment is a three-function full configuration solution applied to a 13L diesel engine for heavy-duty commercial vehicles. The overall structure is shown in Figure 1, including the internal combustion engine body 1, exhaust waste heat recovery unit, fully closed-loop steam circulation unit, coaxial power output unit, heat dissipation-condensation coordination unit, liquid storage and pressure stabilization unit, and intelligent control unit.

[0029] The exhaust waste heat recovery unit includes a waste heat evaporator 4 and an internal combustion engine exhaust pipe 2. The internal combustion engine exhaust pipe 2 passes through the internal heat exchange chamber of the waste heat evaporator 4. Spiral reinforced heat exchange fins 3 are uniformly welded to the outer wall of the exhaust pipe 2. The waste heat evaporator 4 is a shell-and-tube heat exchanger, and its interior is filled with R245fa low-boiling-point organic working fluid as the circulating working fluid.

[0030] The fully closed-loop steam circulation unit includes a steam delivery pipe 5, a steam turbine 6, a waste steam return pipe 14, a condenser 15, a liquid storage tank 17, a working fluid circulation pump 19, and a one-way check valve 20. The top steam outlet of the waste heat evaporator 4 is connected to the air inlet of the steam turbine 6 through the steam delivery pipe 5. The steam turbine 6 is a small radial-flow steam turbine with a rated working pressure of 0.4-1.2 MPa. The bottom air outlet of the steam turbine 6 is connected to the air inlet of the condenser 15 through the waste steam return pipe 14. The liquid outlet of the condenser 15 is connected to the liquid inlet of the liquid storage tank 17 through a pipeline. The liquid outlet of the liquid storage tank 17 is connected to the bottom liquid inlet of the waste heat evaporator 4 through the working fluid circulation pump 19 and the one-way check valve 20, forming a fully closed and leak-free circulation loop.

[0031] The coaxial power output unit includes a coaxial drive shaft 7 and three independently controllable power output modules. The power output shaft of the steam turbine 6 is fixedly connected to the coaxial drive shaft 7. The three power output modules are connected in series from left to right along the coaxial drive shaft 7: the first group is a generator module 8, equipped with a first controllable clutch mechanism 9; the second group is a cooling fan drive module 10, equipped with a second controllable clutch mechanism 11; and the third group is an auxiliary power coupling module 12, equipped with a third controllable clutch mechanism 13. The output end of the generator module 8 is connected to the vehicle battery 24 through a voltage regulator and rectifier module 23. The auxiliary power coupling module 12 includes a reduction gear set 25 and a coupling 26. The output end of the reduction gear set 25 is coupled to the crankshaft 27 of the internal combustion engine through the coupling 26.

[0032] The heat dissipation-condensation coordination unit includes an internal combustion engine radiator 16, a condenser 15 which is attached and fixed to the windward side of the internal combustion engine radiator 16, and a cooling fan of the cooling fan drive module 10 which is arranged facing the internal combustion engine radiator 16 and the condenser 15, so that the air cooling of both can be realized simultaneously.

[0033] The intelligent control unit includes a detection component 21 and a controller 22. The detection component 21 includes a temperature sensor, a pressure sensor, a speed sensor, and a liquid level sensor. Each sensor is installed at its corresponding monitoring position, and the signal output terminals of each sensor are electrically connected to the controller 22. The controller 22 is electrically connected to the working fluid circulation pump 19, the first controllable clutch mechanism 9, the second controllable clutch mechanism 11, and the third controllable clutch mechanism 13, respectively.

[0034] The working process of this embodiment is as follows: (1) When the diesel engine starts and runs, the exhaust temperature rises to above 180°C. The high-temperature exhaust flows through the internal combustion engine exhaust pipe 2 and then through the waste heat evaporator 4. The enhanced heat exchange fins 3 transfer the exhaust waste heat to the R245fa working fluid. The working fluid absorbs heat and vaporizes to form high-pressure steam. The detection component 21 monitors the circulation parameters in real time and transmits them to the controller 22; (2) Under idling conditions, the steam pressure is below 0.3MPa. The controller 22 controls the first controllable clutch mechanism 9 to engage, and the second and third controllable clutch mechanisms to disengage, switching to pure power generation mode. The steam turbine 6 only drives the generator to run, and the generated electrical energy is stored in the vehicle battery 24 to achieve positive energy-saving benefits; (3) Under medium-speed normal conditions, the steam pressure reaches 0.3MPa. The controller 22 controls the first and second controllable clutch mechanisms to engage, and the third controllable clutch mechanism to disengage, switching to power generation + heat dissipation dual-function mode. The steam turbine 6 (4) Under high-speed heavy-load conditions, the steam pressure reaches 0.8MPa. The controller 22 controls all three sets of controllable clutch mechanisms to engage and switch to the three-function synchronous operation mode. The steam turbine 6 synchronously realizes power generation, heat dissipation drive and auxiliary power output, providing auxiliary power for vehicle driving and reducing diesel fuel consumption. (5) The exhaust steam after doing work enters the condenser 15 through the exhaust steam return pipe 14. After condensing into liquid working fluid, it flows into the storage tank 17. After being pressurized by the working fluid circulation pump 19, it flows back to the waste heat evaporator 4 to complete the closed-loop circulation.

[0035] According to actual vehicle testing, the comprehensive fuel saving rate of this embodiment reaches 12.8% under long-distance highway conditions and 17.2% under heavy-load conditions in mountainous areas. The comprehensive thermal efficiency of the diesel engine is improved by 10.3%, and the operation stability is excellent. Example 2

[0036] This embodiment is a pure power generation mode scheme, applied to a stationary internal combustion engine generator set. The overall structure is shown in Figure 2. The difference from Embodiment 1 is that only the generator module 8 and the first controllable clutch mechanism 9 are connected in series on the coaxial transmission shaft 7. There is no cooling fan drive module and auxiliary power coupling module. The condenser 15 is integrated with the generator set radiator. The cooling fan is driven by the original cooling system of the generator set. The generator output is connected to the generator set auxiliary power system and energy storage battery.

[0037] In this embodiment, all the exhaust waste heat from the internal combustion engine is used for closed-loop steam power generation to supply the auxiliary power systems of the generator set, such as control, lighting, and heat dissipation. This eliminates the need for the generator set to drive an auxiliary generator, reducing the generator set's fuel consumption by 6.5%. This method is suitable for scenarios such as stationary power generation and ship backup power generation. Example 3

[0038] This embodiment is a pure heat dissipation drive mode scheme, applied to a 2.0L passenger car gasoline engine. The overall structure is shown in Figure 3. The difference from Embodiment 1 is that only the cooling fan drive module 10 and the second controllable clutch mechanism 11 are connected in series on the coaxial transmission shaft 7. There is no generator module and auxiliary power coupling module. The controller controls the start, stop and speed of the cooling fan according to the engine water temperature and steam pressure.

[0039] In this embodiment, all the waste heat from the internal combustion engine exhaust is used to drive the cooling fan, completely eliminating the traditional belt-driven fan and electric fan, and completely eliminating the engine parasitic load on the cooling system. This can reduce the overall fuel consumption of passenger cars by 4.2%, and the fuel saving rate under high-speed conditions reaches 5.8%. Example 4

[0040] This embodiment is a pure auxiliary power mode scheme applied to large marine diesel engines. The overall structure is shown in Figure 4. The difference from Embodiment 1 is that only the auxiliary power coupling module 12 and the third controllable clutch mechanism 13 are connected in series on the coaxial transmission shaft 7. There is no generator module and cooling fan drive module. The output end of the auxiliary power coupling module is coupled to the ship's propulsion shaft system through a reduction gear set and a coupling.

[0041] In this embodiment, all the waste heat from the internal combustion engine exhaust is used to provide auxiliary power for the ship's propulsion shaft system. Under continuous high-load navigation conditions, the main engine fuel consumption can be reduced by 9.7%, significantly improving the ship's navigation economy. Example 5

[0042] This embodiment is a dual-function combination scheme of power generation and heat dissipation, applied to the diesel engine of excavator construction machinery. The difference from embodiment 1 is that: the generator module 8 and the cooling fan drive module 10 are connected in series on the coaxial drive shaft 7, without an auxiliary power coupling module. The generator output is connected to the excavator's on-board power grid to supply the hydraulic system control unit and the electrical equipment in the cab. The cooling fan simultaneously realizes engine heat dissipation and condenser condensation.

[0043] In this embodiment, the parasitic load of the excavator's cooling fan can be completely eliminated, while power is supplied to the vehicle's electrical system. This adapts to the excavator's frequent start-stop and variable load operating conditions, achieving a comprehensive fuel saving rate of 8.3%. Example 6

[0044] This embodiment is a dual-function combination scheme of heat dissipation and auxiliary power, applied to the diesel engine of mining engineering machinery. The difference from embodiment 1 is that: the cooling fan drive module 10 and the auxiliary power coupling module 12 are connected in series on the coaxial transmission shaft 7, without a generator module. The output end of the auxiliary power coupling module is coupled to the hydraulic main pump of the engineering machinery to provide auxiliary power for the hydraulic system.

[0045] This embodiment is adapted to the heavy-duty and high-temperature operating conditions of mining machinery, which can reduce the engine cooling load and supplement the power of the hydraulic system, with a comprehensive fuel saving rate of 11.5%.

Claims

1. A closed-loop steam energy-saving drive device based on waste heat from internal combustion engine exhaust, characterized in that, The system includes an internal combustion engine body, an exhaust waste heat recovery unit, a fully closed-loop steam circulation unit, a coaxial power output unit, a heat dissipation-condensation coordination unit, a liquid storage and pressure stabilization unit, and an intelligent control unit. The exhaust waste heat recovery unit includes a waste heat evaporator and an internal combustion engine exhaust pipe. The exhaust pipe passes through the internal heat exchange chamber of the waste heat evaporator, and reinforced heat exchange fins are fixed to the outer wall of the exhaust pipe. The waste heat evaporator is filled with a closed-loop working fluid. The fully closed-loop steam circulation unit includes a steam delivery pipe, a steam turbine, a waste steam return pipe, a condenser, a liquid storage tank, a working fluid circulation pump, and a one-way check valve. The steam outlet of the waste heat evaporator is connected to the inlet of the steam turbine via the steam delivery pipe, and the outlet of the steam turbine is connected to the inlet of the condenser via the waste steam return pipe. The liquid outlet of the condenser... The liquid inlet of the storage tank is connected via a pipeline, and the outlet of the storage tank is connected to the inlet of the waste heat evaporator via a working fluid circulation pump and a one-way check valve, forming a fully enclosed, leak-free circulation loop. The circulating working fluid undergoes only a gas-liquid phase change within the loop and is not discharged externally. The coaxial power output unit includes a coaxial drive shaft and at least one set of independently controllable power output modules. The power output shaft of the steam turbine is fixedly connected to the coaxial drive shaft, and the power output modules are installed in series on the coaxial drive shaft. The power output modules can be any one or more combinations of a generator module, a cooling fan drive module, and an auxiliary power coupling module. The cooling... The condensation coordination unit includes an internal combustion engine radiator, with the condenser fixedly attached to the windward side of the radiator. The cooling fan of the cooling fan drive module is positioned directly opposite the radiator and condenser, enabling simultaneous cooling of the radiator and condensation of exhaust vapor in the condenser. The intelligent control unit includes a detection component and a controller. The signal output terminal of the detection component is electrically connected to the controller, which is electrically connected to the working fluid circulation pump and the controllable clutch mechanism of each power output module.

2. The apparatus according to claim 1, characterized in that, The power output module contains only a generator module, which includes a generator rotor and a controllable clutch mechanism. The generator rotor is fixed on a coaxial transmission shaft, and the controllable clutch mechanism is located between the generator rotor and the steam turbine. The generator output is connected to the equipment's energy storage battery and the entire machine's electrical load through a voltage stabilizing and rectifying module.

3. The apparatus according to claim 1, characterized in that, The power output module only includes a cooling fan drive module, which includes a cooling fan and a controllable clutch mechanism. The driving end of the controllable clutch mechanism is fixedly connected to the coaxial transmission shaft, and the driven end is fixedly connected to the cooling fan.

4. The apparatus according to claim 1, characterized in that, The power output module only includes an auxiliary power coupling module, which includes a reduction gear set, a coupling, and a controllable clutch mechanism. The driving end of the controllable clutch mechanism is fixedly connected to the coaxial transmission shaft, and the driven end is connected to the input end of the reduction gear set. The output end of the reduction gear set is coupled to the power output system of the internal combustion engine body through the coupling.

5. The apparatus according to claim 1, characterized in that, The power output module includes a combination of a generator module and a cooling fan drive module. The two modules are connected in series along a coaxial transmission shaft, and each module is equipped with an independent controllable clutch mechanism.

6. The apparatus according to claim 1, characterized in that, The power output module includes a combination of a cooling fan drive module and an auxiliary power coupling module. The two modules are connected in series along a coaxial transmission shaft, and each module is equipped with an independent controllable clutch mechanism.

7. The apparatus according to claim 1, characterized in that, The power output module includes a combination of a generator module and an auxiliary power coupling module. The two modules are connected in series along a coaxial transmission shaft, and each module is equipped with an independent controllable clutch mechanism.

8. The apparatus according to claim 1, characterized in that, The power output module includes a generator module, a cooling fan drive module, and an auxiliary power coupling module connected in series along a coaxial transmission shaft. All three modules are equipped with independent controllable clutch mechanisms.

9. The apparatus according to claim 1, characterized in that, The waste heat evaporator is a shell-and-tube finned heat exchanger, the internal combustion engine exhaust pipe is the heat exchange tube, the circulating working fluid flows on the shell side, and the enhanced heat exchange fins are spiral or straight structures, uniformly welded to the outer wall of the exhaust pipe; the steam turbine is a small radial-flow steam turbine or a vortex expander, and the circulating working fluid is deionized water or a low-boiling-point organic Rankine cycle working fluid.

10. The apparatus according to claim 4, characterized in that, The internal combustion engine power output system includes an internal combustion engine crankshaft, a gearbox input shaft, a hydraulic main pump for construction machinery, a ship propulsion shaft system, and a generator set power end. The auxiliary power coupling mechanism can be coupled with any type of power output system. The equipment energy storage battery and the total electrical load of the machine include vehicle-mounted batteries, construction machinery vehicle-mounted power grids, shipboard electrical systems, and stationary generator set auxiliary power systems.

11. The apparatus according to claim 1, characterized in that, The liquid storage tank is equipped with a liquid level sensor and a pressure stabilizing air bag. The liquid level sensor is electrically connected to the controller. The detection components include a temperature sensor, a pressure sensor, and a speed sensor. The temperature sensor is respectively installed inside the waste heat evaporator, at the exhaust pipe outlet of the internal combustion engine, and at the liquid outlet of the condenser. The pressure sensor is installed inside the steam delivery pipe, and the speed sensor is installed at the coaxial drive shaft.

12. A closed-loop energy-saving method for exhaust waste heat from an internal combustion engine based on the device described in any one of claims 1-11, characterized in that, Includes the following steps: (1) Waste heat absorption and steam generation stage: The main body of the internal combustion engine starts and runs. The high-temperature exhaust flows through the exhaust pipe of the internal combustion engine to the waste heat evaporator. The exhaust waste heat is transferred to the circulating working fluid through the enhanced heat exchange fins. The working fluid absorbs heat and vaporizes to form high-pressure steam. The detection component monitors the circulation parameters in real time and transmits them to the controller; (2) Power matching and drive control stage: The high-pressure steam enters the steam turbine through the steam delivery pipe. It drives the impeller to rotate and converts the internal energy of the steam into mechanical energy, which drives the coaxial drive shaft to rotate. The controller controls the controllable clutch mechanism of the corresponding power output module to engage / disengage according to the operating conditions of the internal combustion engine, the circulation parameters and the load requirements. Disconnect to achieve single-function independent operation or multi-function synchronous operation; (3) Exhaust steam condensation and closed-loop reflux stage: The exhaust steam after the steam turbine does work enters the condenser through the exhaust steam reflux pipe, and is condensed into liquid working fluid under the air cooling effect of the cooling fan. After the liquid working fluid flows into the storage tank for pressure stabilization, it is pressurized by the working fluid circulation pump and returned to the waste heat evaporator by the one-way check valve to complete the fully closed-loop cycle; (4) Intelligent control stage under all working conditions: The controller receives the monitoring data of the detection component in real time, and dynamically adjusts the flow rate of the working fluid circulation pump and the clutch state of each power output module according to the internal combustion engine water temperature, exhaust temperature, steam pressure and equipment load to adapt to the stable operation of the internal combustion engine under all working conditions.

13. The method according to claim 12, characterized in that, In step (2), the single-function independent operation mode includes: Pure power generation mode: The controller only controls the controllable clutch mechanism of the generator module to engage, while the other modules are disengaged. The steam turbine only drives the generator to run, realizing waste heat recovery and power generation. Pure heat dissipation drive mode: The controller only controls the controllable clutch mechanism of the cooling fan drive module to engage, while the other modules are disengaged. The steam turbine only drives the cooling fan to run, realizing waste heat-driven heat dissipation. Pure auxiliary power mode: The controller only controls the engagement of the controllable clutch mechanism of the auxiliary power coupling module, while the other modules are disengaged. The steam turbine only provides auxiliary power to the internal combustion engine power output system.

14. The method according to claim 12, characterized in that, In step (2), the multi-functional synchronous operation mode includes any two functions combined operation and three functions operating synchronously. The controller adjusts the output power distribution of each module according to the load demand.

15. The method according to claim 12, characterized in that, When the equipment is construction machinery or an internal combustion engine is under frequent load changes, the controller synchronously receives the pressure signal from the hydraulic system of the construction machinery and dynamically adjusts the output torque and clutch status of the auxiliary power coupling module according to the hydraulic load. When the equipment is a ship or an internal combustion engine is under continuous high load navigation conditions, the controller controls the auxiliary power coupling module to remain closed to provide auxiliary power to the ship's propulsion shaft system, and the electrical energy generated by the generator is synchronously connected to the ship's electrical system.

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