阅读说明：本技术 一种气液两相转化高能量存储密度液压蓄能器 (Gas-liquid two-phase conversion high-energy storage density hydraulic accumulator ) 是由 周连佺 刘强 薄晓楠 张楚 瞿炜炜 王伟平 于 2019-11-07 设计创作，主要内容包括：一种气液两相转化高能量存储密度液压蓄能器,包括活塞杆、活塞、缸筒、温控装置。有杆腔用于容纳液压油,无杆腔用于容纳气体,位于有杆腔一端的缸桶壁上具有液压油口,液压油口连接外部液压系统,活塞杆和活塞的轴心为空心结构,伸出缸筒的活塞杆一端具有充气孔,温控装置安装在缸筒外围使缸筒内气体温度处于该气体临界温度以下。本发明的气液两相转化高能量存储密度液压蓄能器,使充入气体保持在略低于临界温度的状态,气体被加压到一定压力后液化,体积缩小,使缸筒可以容纳更多的液压油用于蓄能,提高了蓄能器的储能密度,减小了蓄能器的容积,节省了占用空间,对于节约移动液压设备有限的工作空间具有重要意义。(A gas-liquid two-phase conversion high-energy storage density hydraulic accumulator comprises a piston rod, a piston, a cylinder barrel and a temperature control device. The rod cavity is used for containing hydraulic oil, the rodless cavity is used for containing gas, a hydraulic oil port is formed in the wall of the cylinder barrel at one end of the rod cavity and connected with an external hydraulic system, the axis of the piston rod and the axis of the piston are of a hollow structure, an inflation hole is formed in one end of the piston rod extending out of the cylinder barrel, and the temperature control device is installed on the periphery of the cylinder barrel to enable the temperature of the gas in the cylinder barrel to be below the critical temperature of the gas. The gas-liquid two-phase conversion high-energy storage density hydraulic accumulator disclosed by the invention has the advantages that the charged gas is kept in a state slightly lower than the critical temperature, the gas is liquefied after being pressurized to a certain pressure, the volume is reduced, more hydraulic oil can be contained in a cylinder barrel for energy storage, the energy storage density of the accumulator is improved, the volume of the accumulator is reduced, the occupied space is saved, and the high-energy storage density hydraulic accumulator has important significance for saving the limited working space of mobile hydraulic equipment.)

1. A gas-liquid two-phase conversion high-energy storage density hydraulic accumulator is characterized by comprising a piston rod, a piston, a cylinder barrel and a temperature control device;

the piston is arranged in the cylinder barrel, one end of the piston rod is fixed with the piston, the other end of the piston rod extends out of the cylinder barrel, the rod cavity is used for containing hydraulic oil, the rodless cavity is used for containing gas, a hydraulic oil port is arranged on the wall of the cylinder barrel at one end of the rod cavity and is used for connecting the rod cavity with a hydraulic system outside the cylinder barrel, the axes of the piston rod and the piston are of a hollow structure, one end of the piston rod extending out of the cylinder barrel is provided with an inflation hole, and the inflation hole is communicated with the rodless cavity through the hollow structure;

the temperature control device is arranged on the periphery of the cylinder barrel and used for regulating and controlling the temperature of the gas in the cylinder barrel so that the temperature of the gas in the cylinder barrel is below the critical temperature of the gas;

when energy is stored, hydraulic oil outside the cylinder barrel enters the rod cavity through the hydraulic oil port, and when acting force of the hydraulic oil on the piston is larger than that of gas in the piston cavity on the piston, the piston compresses gas in the rodless cavity;

when energy is released, the pressure of an external oil way is reduced, the acting force of gas in the rodless cavity on the piston is larger than that of hydraulic oil on the piston, the piston presses the hydraulic oil, and the hydraulic oil in the piston rod cavity is discharged from the hydraulic oil port and is supplied to an external hydraulic system for use.

2. The hydraulic accumulator for high energy storage density through gas-liquid two-phase conversion as claimed in claim 1, wherein the temperature control device is a thermostat device for keeping the temperature of the gas in the cylinder at a set temperature 1-2 ℃ lower than the critical temperature of the gas.

3. The hydraulic accumulator of claim 2, wherein the thermostatic device is a heat exchanger, and when the temperature of the gas in the cylinder is higher than a predetermined temperature, cold water is introduced into the heat exchanger to dissipate the heat of the gas in the cylinder; when the temperature of the gas in the cylinder barrel is lower than the set temperature, hot water is introduced into the heat exchanger to heat the gas in the cylinder barrel; and when the temperature of the gas in the cylinder barrel is equal to the set temperature, closing the heat exchanger.

4. The hydraulic accumulator of claim 2, wherein the thermostat comprises a heating device and a cooling device, the heating device is a heat exchanger, the cooling device comprises a finned cooler and a cooling fan, and when the temperature of the gas in the cylinder is higher than a set temperature, the cooling fan is started to blow the finned cooler to dissipate the heat of the gas in the cylinder; when the temperature of the gas in the cylinder barrel is lower than the set temperature, hot water is introduced into the heat exchanger to heat the gas in the cylinder barrel; and when the temperature of the gas in the cylinder barrel is equal to the set temperature, the heating device and the cooling device are closed.

5. The gas-liquid two-phase conversion high energy storage density hydraulic accumulator of claim 1, wherein the gas is CO ₂Or other gases that can be liquefied and vaporized under pressure at operating temperatures.

6. The gas-liquid two-phase conversion high energy storage density hydraulic accumulator of claim 1, wherein the CO is ₂The temperature of (a) is 29 to 31 ℃.

Technical Field

The invention belongs to the field of hydraulic transmission and control, particularly relates to the field of hydraulic energy storage, and particularly relates to a gas-liquid two-phase conversion high-energy storage density hydraulic energy accumulator.

Background

A hydraulic accumulator is an energy storage device in a hydropneumatic system. The energy in the system is converted into compression energy or potential energy to be stored at a proper time, and when the system needs the energy, the compression energy or the potential energy is converted into hydraulic energy or air pressure and the like to be released, and the energy is supplied to the system again. When the system pressure is increased instantaneously, it can absorb the energy of the part to ensure the pressure of the whole system is normal.

The energy accumulator can be divided into a weight type, a spring type and a gas loading type according to the loading mode, and the gas loading type is most used at present. Gas-loaded accumulators are divided into gas-bag, gas-bottle and piston types. The piston type energy accumulator has oil-gas isolation, reliable operation and long service life, and is suitable for high-pressure and high-capacity energy storage.

The oil pressure of the existing piston type energy accumulator is equal to the gas pressure, the volume and the weight are large, the cost is also very high, along with the increase of the volume of the stored oil, the pressure is also increased, the pressure change of the stored oil is large, and the pressure change is also large when the oil is released. The existing piston type energy accumulator uses a piston to isolate oil liquid for storing energy from compressed gas, the gas is nitrogen, and the volume can be reduced only by compression and the gas cannot be liquefied. For example, if the volume of the energy storage oil is required to be 30L and the pressure variation range is 15-20MPa, the calculated required volume of the energy storage device is 190L and the external volume is 250L. If the mobile equipment uses the piston type energy accumulator to store energy, the large volume occupies large space of the mobile equipment, influences the sight line and has high cost.

Disclosure of Invention

The invention aims to provide a gas-liquid two-phase conversion high-energy storage density hydraulic energy accumulator, which reduces the volume of the prepared energy accumulator and saves the occupied working space by improving the energy storage density of the energy accumulator under the condition of meeting certain energy storage volume and pressure.

In order to achieve the above object, the technical solution of the present invention is as follows:

a gas-liquid two-phase conversion high-energy storage density hydraulic accumulator comprises a piston rod, a piston, a cylinder barrel and a temperature control device. The piston is arranged in the cylinder barrel, one end of the piston rod is fixed with the piston, the other end of the piston rod extends out of the cylinder barrel, the rod cavity is used for containing hydraulic oil, the rodless cavity is used for containing gas, a hydraulic oil port is formed in the wall of the cylinder barrel at one end of the rod cavity and used for being connected with a rod cavity and a hydraulic system outside the cylinder barrel, the axes of the piston rod and the piston are of a hollow structure, an inflation hole is formed in one end of the piston rod extending out of the cylinder barrel, and the inflation hole is communicated with the rodless cavity through the hollow. The temperature control device is arranged on the periphery of the cylinder barrel and used for regulating and controlling the temperature of the gas in the cylinder barrel so that the temperature of the gas in the cylinder barrel is below the critical temperature of the gas. When energy is stored, hydraulic oil outside the cylinder barrel enters the rod cavity through the hydraulic oil port, and when acting force of the hydraulic oil on the piston is larger than that of gas in the piston cavity on the piston, the piston compresses gas in the rodless cavity; when energy is released, the pressure of an external oil way is reduced, the acting force of gas in the rodless cavity on the piston is larger than that of hydraulic oil on the piston, the piston presses the hydraulic oil, and the hydraulic oil in the piston rod cavity is discharged from the hydraulic oil port and is supplied to an external hydraulic system for use.

Further, the temperature control device is a constant temperature device, the constant temperature device is used for keeping the temperature of the gas in the cylinder barrel at a set temperature, the set temperature is 1-2 ℃ lower than the critical temperature of the gas, and the gas can be liquefied only when the pressure of the gas is increased below the critical temperature.

Further, the constant temperature device is a heat exchanger, and when the temperature of the gas in the cylinder barrel is higher than the set temperature, cold water is introduced into the heat exchanger to dissipate the heat of the gas in the cylinder barrel; when the temperature of the gas in the cylinder barrel is lower than the set temperature, hot water is introduced into the heat exchanger to heat the gas in the cylinder barrel; when the gas temperature in the cylinder is equal to the set temperature, the heat exchanger is closed.

Further, the constant temperature device comprises a heating device and a cooling device, the heating device is a heat exchanger, the cooling device comprises a finned cooler and a cooling fan, and when the temperature of the gas in the cylinder barrel is higher than a set temperature, the cooling fan is started to blow the finned cooler to dissipate the heat of the gas in the cylinder barrel; when the temperature of the gas in the cylinder barrel is lower than the set temperature, hot water is introduced into the heat exchanger to heat the gas in the cylinder barrel; and when the temperature of the gas in the cylinder barrel is equal to the set temperature, the heating device and the cooling device are closed.

Further, the gas is CO ₂Or other gases that can be liquefied and vaporized under pressure at operating temperatures.

Further, said CO ₂The temperature of (a) is 29 to 31 ℃.

Compared with the prior art, the invention has the beneficial effects that:

the oil pressure of the existing piston type energy accumulator is equal to the gas pressure, the volume and the weight are large, the cost is also very high, along with the increase of the volume of the stored oil, the pressure is also increased, the pressure change of the stored oil is large, and the pressure change is also large when the oil is released. The gas-liquid two-phase conversion high-energy storage density hydraulic energy accumulator provided by the invention has the advantages that the charged gas is kept in a state slightly lower than the critical temperature, the gas is liquefied after being pressurized to a certain pressure and is changed into a liquid state, the volume is reduced, more hydraulic oil can be contained in a cylinder barrel for energy storage, the energy storage density of the energy accumulator is improved under the condition of meeting the required energy storage volume and pressure, the volume of the energy accumulator is reduced, the occupied space is saved, the cost of the energy accumulator is reduced, and the energy accumulator has important significance for saving the limited working space of mobile hydraulic equipment.

Drawings

Fig. 1 is a schematic structural diagram of a gas-liquid two-phase conversion high-energy storage density hydraulic accumulator in embodiment 1 of the present invention;

in fig. 1: 1. a piston rod; 2. a piston; 3. a cylinder barrel; 4. a heat exchanger; 5. a cooling fan; 6. a finned cooler; A. a hydraulic oil port; B. and (4) an air inflation hole.

Detailed Description

The invention is described in detail below with reference to the figures and the specific embodiments.