CN100398900C

CN100398900C - Method for obtaining high-temperature hot fluid based on multi-layer piping structure

Info

Publication number: CN100398900C
Application number: CNB2005100392070A
Authority: CN
Inventors: 陈红丽; 吴宜灿
Original assignee: Institute of Plasma Physics of CAS
Current assignee: Institute of Plasma Physics of CAS
Priority date: 2005-04-30
Filing date: 2005-04-30
Publication date: 2008-07-02
Anticipated expiration: 2025-04-30
Also published as: CN1755183A

Abstract

The present invention discloses a method for obtaining high-temperature hot fluid based on a multi-layer pipeline structure. The temperature of a fluid outlet is improved in the way that a multi-layer flow channel inner lining is added in a flow channel, and the temperature, the stress and the deformation of pipe wall material and inner lining material of each layer are ensured to be in the range of permission. RAFM steel with low high-temperature resistance and larger stress intensity is particularly applied to high temperature reactors and is used as structural material, SiCf/SiC composite material with good high-temperature resistance and smaller stress intensity is used as inner lining material, the technical difficulty of the structure design of the high-temperature reactors is reduced, the temperature of a refrigerant outlet is increased, and the feasibility and the competitiveness of high-temperature power generation and hydrogen manufacture of nuclear energy are improved.

Description

Obtain the method for high-temperature hot fluid based on multi-layer piping structure

Technical field

The present invention relates to calorifics, materials science and application thereof, a kind of specifically method that obtains high-temperature hot fluid based on multi-layer piping structure.

Technical background

In order to obtain high temperature fluid, usual way has the nuclear reactor neutron radiation of reception or heat-producing chemical reaction takes place or heating equipment is set in runner in runner inside, needs pipeline inevitably in the process that produces high temperature fluid.For high temperature fluid, just require the pipeline material can be high temperature resistant.Because fluid line need bear the influence of various power such as internal fluid pressure, fluid scouring and external action, so pipeline material is selected to satisfy heavily stressed requirement of strength simultaneously.And the temperature of material raises, and corresponding allowable stress descends, and only the stress intensity of correspondence is just very big when temperature is low, and requiring material at high temperature and high strength when therefore realizing hot fluid with single tube is a challenge to material itself.Selection meets the material that tube wall high strength requires and does the high temperature requirement that structural pipe wall can't satisfy fluid, and the material of selecting to meet the requirement of tube wall high temperature is done structural pipe wall and can't be satisfied heavily stressed requirement of strength.

Especially, to present countries in the world all at the high-temperature reactor of the employing nuclear reaction neutron radiation of endeavouring to study.The reactor coolant output temperature is high more, and thermal conversion efficiency is high more, and nuclear energy power generation, hydrogen manufacturing benefit are also high more.Therefore in order to increase the benefit, adopt different technology, different materials improves the outlet temperature of freezing mixture.Wherein material choose the most key, the material that is used for reactor structure at present mainly contains: low activation ferrite/martensite steel (RAFM), alum base alloy and silicon carbide (SiCf/SiC) composite material etc., wherein RAFM steel technology is ripe relatively, stress intensity is big, but the maximum functional allowable temperature has only 550 ℃ during irradiation, causes coolant outlet temperature to be limited to this number.And the SiCf/SiC composite material has superior high-temperature behavior (can reach 1000 ℃), but maximum allowable stress is lower, and a lot of technology that is that all right is ripe.Adopt at present the reactor of RAFM steel can't obtain the freezing mixture of higher outlet temperature in the world, and high-temperature reactor mostly adopts the SiCf/SiC composite material, because the high temperature nuclear reactor building technology difficulty of SiCf/SiC composite material is big, even coolant outlet temperature improves, its feasibility, competitiveness are not high yet.

Summary of the invention

The present invention is directed to the problem of above-mentioned appearance, adopt the single tube structure can't satisfy the requirement of high temperature fluid, propose a kind of method that obtains high-temperature hot fluid based on multi-layer piping structure pipe wall material.Particularly in high-temperature reactor is used, adopt that technology maturation, resistance to high temperature are lower, the big RAFM steel of stress intensity is made structural material, and high temperature resistant SiCf/SiC composite material increases coolant outlet temperature as the structure liner, improves the feasibility and the competitiveness of nuclear energy power generation, hydrogen manufacturing.

Technological scheme of the present invention

Obtain the method for high-temperature hot fluid based on multi-layer piping structure, it is characterized in that the liner pipe that sheathed a plurality of internal diameters successively decrease successively in outer layer pipe, end at pipeline, except that outer pipeline, from the first layer liner pipe, the end of every liner pipe separately connects as one, and enters the mouth as runner with the runner between the outer layer pipe and first liner pipe; At the pipeline the other end, from outer layer pipe, the end of every liner pipe separately connects as one, and keeps the middle runner of minimum liner pipe as runner exit; Cryogen enters from the runner inlet, by receiving the nuclear reactor neutron radiation or exothermic reaction or electro-heat equipment being set in runner, make fluid flow in the runner that multi-layer piping constitutes, constantly heat temperature raising flows out high-temperature hot fluid from runner exit at last.

Described method is characterized in that the liner pipe that a plurality of internal diameters sheathed in described outer layer pipe and its successively decrease, and the high temperature resistant degree of its material improves successively.

Described method is characterized in that leaving perforate on the tube wall of liner pipe sheathed in the described outer layer pipe.

Described method is characterized in that described pipeline is 2～6 layers.

Described method, it is characterized in that described outer layer pipe material is the construction of pressure vessel material, wherein sheathed liner pipe is an exotic material, described fluid is gas or liquid, pipeline and fluid receive neutron irradiation or other thermals source, fluid itself constantly heats up, and fluid is 100-500 ℃ in the temperature of flow passage entry, and the temperature at the runner exit place is 500-1000 ℃.

The principle of invention

In order to obtain high temperature fluid, usual way has the nuclear reactor neutron radiation of reception or heat-producing chemical reaction takes place or heating equipment is set in runner in runner inside.For high temperature fluid, just require the pipeline configuration material can be high temperature resistant, and have the influence that big allowable stress bears various power such as internal fluid pressure, fluid scouring and external action simultaneously.And the temperature of material raises usually, and corresponding stress intensity descends, and therefore adopts the single tube structure can't satisfy the requirement of high temperature fluid to pipe wall material.Utilize the construction of pressure vessel material as pipeline configuration, increase liner pipe at pipe interior.The selection of liner pipe material is necessary high temperature resistant and high temperature is following and fluid compatibility is better, one deck liner pipe is set still can't realizes high temperature fluid, because the fluid of the inner excessive temperature of liner must influence the outer wall structure by the conduction of liner, the outer wall structure temperature is exceeded standard and cause stress decrease, and the little inner lining material of selection thermal conductivity, can reduce the conduction of heat to tube wall, but the thermal conductivity that liner is lower can cause liner to produce the bigger temperature difference, make the liner pipe thermal stress increase, even gross distortion.And the multilayer liner pipe is set, and making progressively continuous-flow between every layer of liner pipe of fluid, temperature increases progressively gradually.The inside and outside hydrodynamic pressure equilibrium of liner pipe, liner stress mainly comes from the thermal stress that the temperature difference produces, and other loading tension are less, because every layer of liner internal-external temperature difference is little, therefore the stress of runner liner is not very big, inner lining material allowable stress features of smaller when satisfying high temperature.Finally guaranteeing to obtain the higher hot fluid of temperature under the pipeline material temperature prerequisite bigger than low stress.

Effect of the present invention

The present invention utilizes the construction of pressure vessel material as outer layer pipe, adopts the resistant to elevated temperatures material of various differences as liner pipe, makes progressively continuous-flow between every layer of liner of fluid, and temperature increases progressively gradually.Under the prerequisite that satisfies pipeline material and liner pipe material safe and feasible, obtain the higher hot fluid of temperature.Material involved in the present invention only need satisfy or require heavily stressed intensity at low temperatures, perhaps requires high temperature resistant and stress intensity is little, has disperseed high temperature and high-intensity requirement simultaneously to material, has solved the infeasibility that realizes hot fluid with single tube.Specifically be applied in the high-temperature reactor and do not adopt heat-resisting quantity high and the bigger RAFM steel of stress intensity is made structural material, high temperature resistant and SiCf/SiC composite material that stress intensity is less is made inner lining material, reduced the technical difficulty of high temperature nuclear reactor structural design, increase coolant outlet temperature, improved feasibility and the competitiveness of the generating of nuclear energy high temperature, hydrogen manufacturing.

Description of drawings

Fig. 1 vertical section structure schematic representation of the present invention.

Fig. 2 cross section structure schematic representation of the present invention.

Embodiment

Referring to Fig. 1,2, the structure shape of actual device can be square, annular or their approximate shapes, and runner liner quantity is determined according to concrete condition.

Obtain the method for high-temperature hot fluid based on multi-layer structure, the runner liner pipe 3 that sheathed a plurality of internal diameters successively decrease successively in pipeline 1, liner pipe 4, liner pipe 6 are to liner pipe 7, end at pipeline 1, except that outer pipeline 1, from liner pipe 3, the end of every pipeline separately connects as one, and enters the mouth 9 with the runner 2 between outer layer pipe 1 and the liner pipe 3 as runner; At pipeline 1 the other end, from outer layer pipe, the end of every pipeline separately connects as one, and the runner 8 that keeps minimum pipeline 7 centres is as runner exit; Cryogen enters from runner inlet 2, by receiving nuclear reaction neutron radiation or other thermals source, makes that when fluid flowed, constantly heat temperature raising flowed out high-temperature hot fluid from runner exit at last in the runner that a plurality of small pipelines constitute.Outer layer pipe 1 with its in the liner pipe 3 that successively decreases of sheathed a plurality of internal diameters, liner pipe 4, liner pipe 6 to liner pipe 7, the high temperature resistant degree of its material improves successively.Leave perforate on the tube wall of sheathed each layer liner pipe in the outer layer pipe 1, allow fluid continuous-flow within it.Described outer layer pipe two ends and liner pipe two-port place are provided with thermal-protective coating 5, and its material is an exotic material.Described outer layer pipe 1 material is the construction of pressure vessel material, wherein sheathed each layer liner pipe is exotic material, described fluid is gas or liquid, pipeline and fluid receive neutron radiation or other thermals source, fluid constantly heats up when flowing, fluid is 100-500 ℃ in the temperature of flow passage entry, and the temperature at the runner exit place is 500-1000 ℃.

Outermost surface is the fluid pipe walls structure, need bear the influence of various power such as internal fluid pressure, fluid scouring and external action, therefore material selects to satisfy the construction of pressure vessel material of heavily stressed intensity, and as long as the ability to bear of temperature is higher slightly than the input temp of fluid.

Runner liner pipe 3 is a first layer runner liner pipe, because of its temperature inside is higher than fluid temperature (F.T.) between pipeline 1 and the liner pipe 3, therefore require this inner lining material more high temperature resistant than pipeline material, consider the heat transfer of inner lining material, the temperature of liner internal flow can influence the temperature of outer layer fluid and even structure, so the inside and outside temperature difference of liner should be too not big.Because liner stress mainly comes from thermal stress, other loading tension are very little, so the stress of runner liner is not very big.Material is selected and can be considered to get final product than pipe wall material is more high temperature resistant by an emphasis.

Runner liner pipe 4, liner pipe 6 are second and third laminar flow road liner pipe, because its inside temperature is higher than outer fluid temperature (F.T.), therefore require inner lining material more high temperature resistant than outer liner, same counter stress do not need to require too big, guarantee that the liner internal-external temperature difference is very little, the maximum stress that satisfies liner is in allowed band.

Runner liner pipe 7 is last laminar flow road liner, and the fluid temperature (F.T.) of this liner inside is the highest, therefore requires this inner lining material the most high temperature resistant, and as exotic materials such as silicon carbide, tungsten alloys, because the temperature difference is little, same counter stress do not need to require too big.

Be the concrete application examples of the present invention on high-temperature nuclear reactor below:

The employing technology is ripe relatively, stress intensity is big, the maximum functional allowable temperature has only 550 ℃ RAFM steel as high-temperature nuclear reactor structural material (being equivalent to outer layer pipe), the plumbous LiPb of freezing mixture lithium (being equivalent to the pipeline inner fluid) flows in structure, in order to improve freezing mixture LiPb outlet temperature, one deck is set in the LiPb runner has electrical insulation and thermal insulation SiCf/SiC liner (being equivalent to liner pipe), electrical insulation mainly is to reduce the MHD pressure drop that liquid metal LiPb flows, and thermal insulation mainly is to improve the LiPb outlet temperature.Because the compatible temperature of LiPb and SiCf/SiC is about 1000 ℃, freezing mixture LiPb outlet temperature can be near 1000 ℃ in theory, but because the non-complete thermal insulation of SiCf/SiC, even the heat-transfer coefficient of SiCf/SiC liner is low, the high temperature of runner inside also can cause structure temperature to be higher than the maximum allowable temperature of RFAM steel, and select the more SiCf/SiC liner of low heat transfer coefficient for use, can cause the liner internal-external temperature difference too big, thereby cause the liner thermal stress to increase, distortion is serious, and these factors have all limited the temperature of LiPb in the liner.Further in first layer SiCf/SiC liner, increase one deck SiCf/SiC liner again, the LiPb of first layer liner is turned in the inflow second layer liner runner, the LiPb temperature can reach 1000 ℃ of high temperature in the second layer liner runner, because the temperature not high (between 550 ℃ and 1000 ℃) of two liner runner LiPb, the internal-external temperature difference of two-layer liner is little, can not cause the thermal stress of structural material temperature exceeding standard and SiCf/SiC liner to exceed standard and gross distortion.

Adopt that stress intensity is big, the maximum functional allowable temperature has only 550 ℃ RAFM steel as the high temperature nuclear reactor structural material, in coolant flow passages, increase two-layer resistant to elevated temperatures SiCf/SiC liner, first layer improves the LiPb temperature and is higher than 550 ℃, the second layer improves about 1000 ℃ of the compatible temperature that the LiPb outlet temperature reaches LiPb and liner, and this design has guaranteed that maximum temperature, maximum stress and the distortion of reactor structural material and two-layer SiCf/SiC liner are all within engineering allows.Because RAFM steel technology is ripe relatively, reduced the technical difficulty of high temperature nuclear reactor structural design, and the increase of coolant outlet temperature, improved the feasibility and the competitiveness of the generating of nuclear energy high temperature, hydrogen manufacturing.

Claims

1. obtain the method for high-temperature hot fluid based on multi-layer piping structure, it is characterized in that the liner pipe that sheathed a plurality of internal diameters successively decrease successively in outer layer pipe, end at pipeline, except that outer pipeline, from the first layer liner pipe, the end of every liner pipe separately connects as one, and enters the mouth as runner with the runner between the outer layer pipe and first liner pipe; At the pipeline the other end, from outer layer pipe, the end of every liner pipe separately connects as one, and keeps the middle runner of minimum liner pipe as runner exit; Cryogen enters from the runner inlet, by receiving the nuclear reactor neutron radiation or heating chemical reaction or electro-heat equipment being set in runner, make fluid flow in the runner that multi-layer piping constitutes, constantly heat temperature raising flows out high-temperature hot fluid from runner exit at last; Its material of described outer layer pipe is low activation ferrite/martensite steel, and the liner pipe material that sheathed a plurality of internal diameters successively decrease in it is the SiCf/SiC composite material, and the high temperature resistant degree of its material improves successively; Leave perforate on the tube wall of sheathed liner pipe in the described outer layer pipe.

2. method according to claim 1, it is characterized in that described fluid is gas or liquid, pipeline and fluid receive neutron radiation, and fluid itself constantly heats up, fluid is 100-500 ℃ in the temperature of flow passage entry, and the temperature at the runner exit place is 500-1000 ℃.