SIMULATION OF TEMPERATURE FIELD IN ULTRA-HIGH FREQUENCY INDUCTION HEATING AND VERIFICATION

An experimental and numerical study on the temperature field induced in the ultra-high frequency induction heating is carried out.With an aim of predicting the thermal history of the workpiece,the influence factors of temperature field,such as the induction frequency,the dimension of coil and the gap between coil and workpiece,are investigated considering temperature-dependent material properties by using FLUX 2Dsoftware.The temperature field characteristic in ultra-high induction heating is obtained and discussed.The numerical values are compared with the experimental results.A good agreement between them is observed with 7.9% errors.

Fabrication and Thermal Structural Characteristics of Ultra-high Temperature Ceramic Struts in Scramjets

ZrB_2-SiC based ultra-high temperature ceramic（UHTC） struts were firstly proposed and fabricated with the potential application in the combustor of scramjets for fuel injection and flame-holding for their machinability and excellent oxidation/ablation resistance in the extreme harsh environment. The struts were machined with electrospark wire-electrode cutting techniques to form UHTC into the desired shape, and with laser drilling to drill tiny holes providing the channels for fuel injection. The integrated thermal-structural characteristic of the struts was evaluated in high-temperature combustion environment by the propane-oxygen free jet facility, subject to the heat flux of 1.5 MW/m^2 lasting for 300 seconds, and the struts maintained integrity during and after the first experiment. The experiments were repeated for verifying the reusability of the struts. Fracture occurred during the second repeated experiment with the crack propagating through the hole. Finite element analysis（FEA） was carried out to study the thermal stress distribution in the UHTC strut. The simulation results show a high thermal stress concentration occurs at the hole which is the crack initiation position. The phenomenon is in good agreement with the experimental results. The study shows that the thermal stress concentration is a practical key issue in the applications of the reusable UHTC strut for fuel injection structure in scramjets.

Rapid Directional Solidification with Ultra-High Temperature Gradient and Cellular Spacing Selection of Cu-Mn Alloy

The detailed laser surface remelting experiments of Cu-31.4 wt pct Mn and Cu-26.6 wt pct Mn alloys on a 5 kW CO2 laser were carried out to study the effects of processing parameters (scanning velocity, output power of laser) on the growth direction of microstructure in the molten pool and cellular spacing selection under the condition of ultra-high temperature gradient and rapid directional solidification. The experimental results show that the growth direction of microstructure is strongly affected by laser processing parameters. The ultra-high temperature gradient directional solidification can be realized on the surface of samples during laser surface remelting by controlling laser processing parameters, the temperature gradient and growth velocity can reach 106 K/m and 24.1 mm/s, respectively, and the solidification microstructure in the center of the molten pool grows along the laser beam scanning direction. There exists a distribution range of cellular spacings under the laser rapid solidification conditions, and the average spacing decreases with increasing of growth rate. The maximum, λmax, minimum, λmin, and average primary spacing, A, as functions of growth rate, Vb, can be given by,λmax=12.54Vb-0.61, λmin=4.47 Vb-0.52, λ=9.09Vb-0.62, respectively. The experimental results are compared with the current Hunt-Lu model for rapid cellular/dendritic growth, and a good agreement is found.

Actions of negative bias temperature instability （NBTI） and hot carriers in ultra-deep submicron p-channel metal-oxide-semiconductor field-effect transistors （PMOSFETs）

Hot carrier injection （HCI） at high temperatures and different values of gate bias Vg has been performed in order to study the actions of negative bias temperature instability （NBTI） and hot carriers. Hot-carrier-stress-induced damage at Vg = Vd, where Vd is the voltage of the transistor drain, increases as temperature rises, contrary to conventional hot carrier behaviour, which is identified as being related to the NBTI. A comparison between the actions of NBTI and hot carriers at low and high gate voltages shows that the damage behaviours are quite different： the low gate voltage stress results in an increase in transconductance, while the NBTI-dominated high gate voltage and high temperature stress causes a decrease in transconductance. It is concluded that this can be a major source of hot carrier damage at elevated temperatures and high gate voltage stressing of p-channel metal-oxide-semiconductor field-effect transistors （PMOSFETs）. We demonstrate a novel mode of NBTI-enhanced hot carrier degradation in PMOSFETs. A novel method to decouple the actions of NBTI from that of hot carriers is also presented.

The construction of technical standard system for ultra deep and high sour gas fields in Northeast Sichuan

To deal with the exploitation difficulties of gas fields in Northeast Sichuan with deep marine strata, after researching the relative standards domestic and abroad extensively, summarizing and promoting the successful experiences and failure lessons of project construction technology application scientifically, Sinopec has established an integrated technical standard system for the exploration and development of ultra deep and high sour gas fields. The system consists of 51 enterprise standards and covers 7 professions including geophysical prospecting, drilling, drilling log, well logging, gas formation test and production, sour gas gathering and transferring system, and HSE (health,safety,environment). It guides and guarantees the safe, high-quality and high-efficiency project construction effectively by means of enhancing the engineering design criterion, recommending the data processing and interpretation methods, identifying the requirements of operation and field inspection and standardizing the application of technical equipments.

DIRECTIONALLY SOLIDIFIED MICROSTRUCTURE OF AN ULTRA-HIGH TEMPERATURE Nb-Si-Ti-Hf-Cr-Al ALLOY

The directionally solidified samples of an ultra-high temperature Nb-Si-Ti-Hf-Cr-Al alloy have been prepared with the use of an electron beam floating zone melting (EBFZM) furnace, and their microstructural characteristics have been analyzed. All the primary dendrites of Nb solid solution (Nbss), eutectic colonies of Nba, plus (Nb, Ti)3 Si/(Nb, Ti)5 Si3 and chains of (Nb, Ti)3 Si/(Nb, Ti)5 Si3 plates align along the growth direction of the samples. With increasing of the withdrawing rate, the microstructure is refined, and the amounts of Nbss+ (Nb, Ti)3 Si/(Nb, Ti)5 Si3 eutectic colonies and (Nb, Ti)3 Si/(Nb, Ti)5 Si3 plates increase. There appear nodes in the (Nb, Ti)3 Si/(Nb, Ti)5 Si3 plates.

High-Sensitivity Ozone Sensing Using 280 nm Deep Ultraviolet Light-Emitting Diode for Detection of Natural Hazard Ozone

Recently ozone is one of natural hazards which comes from cars, industry using ozone for sterilization of organic and inorganic materials and for water purification. So, ozone sensing becomes very important, and convenient and accurate ozone sensor is required. A new high sensitivity ozone sensing system using an deep ultra-violet light emitting diode (DUV-LED) operated at the wavelength of 280 nm has been successfully constructed. The fabrication of diode operated at 280 nm is much easier than that of DUV-LED operated at Hg lamp wavelength of 254 nm. The system is compact and possible to sense the ozone concentration less than 0.1 ppm with an accuracy of 0.5% easily with low power DUV-LED of around 200 micro Watts operated at 280 nm without any data processing circuit.

The temperature-dependent fracture strength model for ultra-high temperature ceramics

Breaking down the entire structure of a material implies severing all the bonds between its atoms either by applying work or by heat transfer. Because bond-breaking is indifferent to either means, there is a kind of equivalence between heat energy and strain energy. Based on this equivalence, we assume the existence of a constant maximum storage of energy that includes both the strain energy and the corresponding equivalent heat energy. A temperaturedependent fracture strength model is then developed for ultrahigh temperature ceramics （UHTCs）. Model predictions for UHTCs, HfB2, TiC and ZrB2, are presented and compared with the experimental results. These predictions are found to be largely consistent with experimental results.

Effects of mechanical boundary conditions on thermal shock resistance of ultra-high temperature ceramics

The effects of mechanical boundary conditions, often encountered in thermalstructural engineering, on the thermal shock resistance（TSR） of ultra-high temperature ceramics（UHTCs） are studied by investigating the TSR of a UHTC plate with various types of constraints under the first, second, and third type of thermal boundary conditions. The TSR of UHTCs is strongly dependent on the heat transfer modes and severity of the thermal environments. Constraining the displacement of the lower surface in the thickness direction can significantly decrease the TSR of the UHTC plate, which is subject to the thermal shock at the upper surface. In contrast, the TSR of the UHTC plate with simply supported edges or clamped edges around the lower surface is much better.

Ultra-High Temperature Gratings

Regenerated gratings seeded by type-I gratings are shown to withstand temperatures beyond 1000 ℃. The method of regeneration offers a new approach to increasing temperature resistance of stable fibre Bragg and other gratings. These ultra-high temperature （UHT） gratings extend the applicability of silicate based components to high temperature applications such as monitoring of smelters and vehicle and aircraft engines to high power fibre lasers.

Experimental study on liquid immiscibility of lamprophyre-sulfide melt at high temperature and high pressure and its geological significance

With lamprophyre and pyrite from the Laowangzhai gold deposit, Yunnan Province, China, as starting materials, and at pressures from 1.5 to 3.0 GPa and temperatures from 1160 to 1560℃ , an experimental study was carried out on the liquid immiscibility of lamprophyre-sulfide melt at high temperature and ultra-high pressure in the DS-29A cubic 3600T/6-type high pressure apparatus. Results showed that the liquid immiscibility of lampro-pyre-sulfide melt in the magmatic system would happen during the early magmatic evolution (high temperature and high pressure conditions) and was controlled by temperature and pressure. The sulfide melt which was separated from the lamprophyric melt would make directional movement in the temperature and pressure field and assemble in the low-temperature and low-pressure region. Because the density of SM is higher than that of the lamprophyric melt, the former would gather together at the bottom of the magma chamber and there would exist a striking boundary between the two melts. On the other hand, the results also suggested that there would be little possibility for lampro-phyric magma to carry massive gold, and lamprophyres can't provide many of oreforming materials (Au) in the processes of gold mineralization.

Ultra-hot Mesoproterozoic evolution of intracontinental central Australia

The Musgrave Province developed at the nexus of the North, West and South Australian cratons and its Mesoproterozoic evolution incorporates a 100 Ma period of ultra-high temperature （UHT） meta- morphism from ca. 1220 to ca. 1120 Ma. This was accompanied by high-temperature A-type granitic magmatism over an 80 Ma period, sourced in part from mantle-derived components and emplaced as a series of pulsed events that also coincide with peaks in UHT metamorphism. The tectonic setting for this thermal event （the Musgrave Orogeny） is thought to have been intracontinental and the lithospheric architecture of the region is suggested to have had a major influence on the thermal evolution. We use a series of two dimensional, fully coupled thermo-mechanical-petrological numerical models to investi- gate the plausibility of initiating and prolonging UHT conditions under model setup conditions appro- priate to the inferred tectonic setting and lithospheric architecture of the Musgrave Province. The results support the inferred tectonic framework for the Musgrave Orogeny, predicting periods of UHT meta- morphism of up to 70 Ma, accompanied by thin crust and extensive magmatism derived from both crustal and mantle sources. The results also appear to be critically dependent upon the specific location of the Mus^rave Province. constrained between thicker cratonic masses.

塔里木油田超深层钻井技术进展及难题探讨

当前,塔里木油田以超深特深层为代表的深地油气资源开发对满足我国经济发展需求和保障能源安全至关重要。经过数十年的探索和实践,塔里木油田创新形成了超深复杂井井身结构设计、超深难钻地层钻井提速、超深大斜度井水平井钻井、超深复杂地层钻完井液、超深复杂地层固井、高温高压井完整性、超深复杂井井控等一系列超深层钻井技术,保障深地油气勘探获得重大突破并创造多项纪录。伴随超深井数量持续增加,工程地质条件更加复杂,井下环境更加苛刻,超深层钻井过程势必面临新的工程难题和挑战,严重制约深地油气资源安全高效开发。为此,通过概括塔里木油田钻井工程技术发展历程,系统梳理了深地钻井工程技术取得的主要技术进展,并结合新的勘探开发形势与油气开发要求,指出了塔里木油田钻井工程技术从超深层迈入特深层新时期的焦点问题及攻关发展方向,为国内外深地复杂油气井安全高效钻进提供借鉴和参考。

中国石化超深层钻完井关键技术挑战及展望

超深层是中国石化油气勘探开发的重要增储上产领域。针对超深层勘探开发需求和高温高压及复杂地质环境带来的工程挑战,中国石化持续开展关键技术攻关,在钻完井基础理论和方法、钻完井装备、高温井筒工作液、耐高温井下工具仪器和完井测试等方面取得关键技术进展,保障了120口超8 000 m油气井的安全钻探,钻深能力突破9 000 m,助推塔里木盆地顺北大型超深油气田建设、四川盆地海相特深层油气勘探开发突破,为保障超深层油气勘探开发提供了有力的工程技术支撑。随着油气勘探开发不断向更深层推进,技术升级转型需求日益迫切,需进一步夯实理论研究基础,突破耐高温关键工具仪器和井筒工作液,加快推进钻完井工程技术向数智化转型,为保障深层、超深层油气高效勘探开发和加快技术升级转型提供工程技术支撑。

抗220℃高温两性离子聚合物降黏剂的制备与性能

针对当前高温高密度水基钻井液流变性调控难题,基于分子结构优化设计和单体优选,制备了新型抗高温两性离子聚合物降黏剂HP-THIN。通过正交实验与单因素实验相结合的方法,对HP-THIN的制备条件进行了优化。采用红外光谱仪、乌氏黏度计和热重分析仪等分别对HP-THIN的分子结构、热稳定性以及相对分子质量进行表征和测定,研究了HP-THIN在220℃超高温条件下对淡水浆、盐水浆、含钙浆和高密度复合盐水浆等不同类型钻井液基浆的降黏性能。在室温下,测试了HP-THIN对基浆黏土颗粒吸附能力、Zeta电位和粒径的影响,并与国内外同类产品(Polythin和xy-27)进行了对比。结果表明,合成降黏剂HP-THIN的反应温度为60℃,反应时间为3 h,引发剂用量和链转移剂用量均为反应单体总量的1%,单体总质量分数为30%;单体AM、AA、AMPS、PTM物质的量比为1.9∶7.5∶2.1∶1。该聚合物的分子结构中含有设计官能团,其黏均相对分子质量约为8211,且具有较好的热稳定性。220℃老化后,HP-THIN在最优加量(0.3%)下对淡水基浆、盐水基浆、含钙基浆和高密度复合盐水基浆的降黏率分别达86%、72%、73%和51%,HP-THIN对不同类型钻井液基浆的高温降黏效果均优于国内外同类产品,相对于xy-27和Polythin,降黏剂HP-THIN对基浆黏土吸附能力强、Zeta电位绝对值大、黏土颗粒尺寸小,可以更好地消除黏土颗粒间网状结构,降低钻井液黏度,具有良好的应用前景。

防漏堵漏低密度水泥浆技术

跃进3-3XC井完钻井深达9432 m,水平钻进距离超过3400 m,刷新了亚洲最深和超深水平大位移井的纪录。该井地质结构复杂,施工难度大,对水泥浆性能要求高,除了高温、高压外,地层承压能力低,极易发生漏失。针对此类问题,通过研发新型功能性材料,构建了C-Lo PSD(1.30 g/cm^(3))、C-Lite STONE(1.60 g/cm^(3))与C-Hi PSD(1.40 g/cm^(3))三套低密度水泥浆体系,涵盖了中低温、高温等应用条件,并在跃进3-3XC井中成功应用,水泥浆性能满足固井需求。与之前用水泥浆体系相比,混浆效率、流变性、悬浮稳定性、水泥石抗压强度等明显提升。其中,C-Lite STONE(T_(BHC)=75℃/T_(TOC)=30℃)与C-Hi PSD(T_(BHC)=145℃/T_(TOC)=105℃)水泥浆体系在温差分别为45℃和40℃下,顶部48 h抗压强度达到8.1 MPa和14.3 MPa。跃进3-3XC井在施工期间多次遭遇漏失,通过使用自研的新型堵漏材料C-B62和C-B66,成功封堵裂缝,保证了固井施工的顺利进行。

塔里木盆地库车山前超深气井砂垢堵塞成因及靶向解除技术

塔里盆地库车山前超深气田是西气东输主力气源地,具有超高温、超高压、高矿化度、储层裂缝非均质性强等特征,气井生产过程中砂垢堵塞问题突出,据统计最高影响气田产能达800×104 m^(3)/d。为实现超深气井高效解堵,通过气水两相结垢热力学预测模型、裂缝性储层岩石力学实验、井筒内气液固流动模拟等研究,揭示了超深气井砂垢复合堵塞成因,并形成了靶向解堵复产关键技术。研究结果表明:①“高温流动压降结垢、裂缝面破裂出砂”是超深气井出砂结垢的内在机理;②结垢固化松散砂桥形成复合堵塞是气井堵塞减产的主要原因,其中靶向除垢是解堵复产的关键所在;③靶向除垢解堵区域为井筒变径处和井周5 m内基质—裂缝系统,气井堵塞率30%~60%为最佳解堵时机;④非酸性除垢解堵液相比常用的酸性解堵液,在同级别溶垢能力的基础上,腐蚀速率降至0.49 g/(m^(2)·h),可同时满足低腐蚀和高效除垢的技术要求。结论认为,形成的超深气井靶向除垢解堵技术在塔里木盆地库车山前超深气田规模应用159井次,有效率达93.3%,累计增产天然气75.08×10^(8)m^(3),已成为西气东输主力气井快速解堵复产的“冬保良方”,可为国内外同类气田解堵复产提供技术借鉴。

塔东区块庆玉1井超深井优快钻井技术

随着油气勘探开发逐步从深层向超深层领域推进,塔东区块储层埋藏深,井下温度高、地质条件异常复杂,使得钻速慢、钻井周期长和钻井风险高。庆玉1井是大庆钻探工程公司在该区块钻的最深的井,为打好打成该井,开展施工难度因素分析,制定技术措施,应用高温仪器、工具、钻井液,施工参数优化等方法,研发超深井配套工艺技术,并结合现场施工要求,实现了塔东区块超深井庆玉1井的优快安全钻井。结果表明:该技术具有安全高效的优点,为深层、超深层油气的经济有效开发提供有效工程技术手段。

超高温陶瓷复合材料研究进展

随着高速飞行器朝着更宽空域、更长时间和更高速度的方向发展,对飞行器的鼻锥、前缘和发动机燃烧室等关键结构的热防护性能提出了更加严苛的要求,发展在极端环境下使用的高性能热防护材料是当前的研究重点。超高温陶瓷复合材料具有优异的抗氧化烧蚀性能,是一类极具应用潜力的非烧蚀型热防护材料。然而,本征脆性问题限制了超高温陶瓷复合材料的工程化应用,需通过组分结构调控对其进行强韧化。同时,飞行器有效载荷提升也对超高温陶瓷复合材料提出了轻量化的要求。本文系统概述了超高温陶瓷复合材料近年来取得的主要研究进展,包括压力烧结、泥浆浸渍、前驱体浸渍裂解、反应熔渗、化学气相渗透/沉积与“固-液”组合工艺等制备方法,颗粒、晶须、软相物质、短切纤维和连续纤维等强韧化方法及其机制,抗氧化烧蚀性能与机理,以及轻量化设计等。讨论了超高温陶瓷复合材料组分、微结构和性能之间的关系,并指出了超高温陶瓷复合材料目前存在的挑战以及未来的发展趋势。

超高速激光熔覆M2+MnS涂层高温摩擦磨损性能研究

通过对比在干摩擦条件下超高速激光熔覆M2+MnS耐磨自润滑涂层与H13基体的高温摩擦磨损性能,深入探讨了温度和载荷对涂层摩擦磨损性能的影响以及磨损机理。采用SEM、EDS、维氏硬度计、摩擦磨损试验机和白光干涉仪等多种仪器对自润滑涂层试样进行了全面的试验表征。结果表明,室温下,涂层平均摩擦因数基本保持稳定;在一定载荷下,随温度升高,涂层平均摩擦因数呈现下降趋势;与基体相比,相同条件下涂层的平均摩擦因数始终较低。M2+MnS涂层的磨损体积随载荷增大近似呈线性增加,且随测试温度的升高先增大后减小。在300℃时,磨损体积达到最大值,而在600℃时最小;涂层在相同条件下磨损体积始终小于基体,室温下为基体的61.96%,而在600℃时为基体的9.48%。研究还揭示了M2+MnS涂层的磨损机理与温度密切相关。温度较低时,主要表现为磨粒磨损,而温度升高时则主要由氧化磨损和磨粒磨损共同作用。