最新刊期
卷 53 ， 期 11 ， 2019
- 摘要：The pre-swirl rotor-stator cavity is an important flow unit in the gas turbine blade air supply system. In order to study the flow characteristics of the gas turbine pre-swirl rotor-stator cavity, a pre-swirl rotor-stator cavity calculation model was established. Using three kinds of pre-swirl ratios(-p=0.48, 0.94 and 1.41), three no--le radial positions(rp/rb=0.8, 0.9 and 1.0), and six kinds of circumferential inclination angles of receiver hole(-=70-, 90-, 100-, 110-, 120-and 135-), the he influences of the circumferential inclination angle of the receiver hole on the flow field distribution and the adiabatic pre-swirl efficiency as well as the discharge coefficient of the receiver hole were analy-ed. The results show that when the radial position of the no--le rp/rb was 0.8, the larger the circumferential inclination angle of the receiver hole was, the larger the discharge coefficient of the receiver hole would be, and t关键词：rotor-stator cavity;receiver hole;flow characteristics204|5|7更新时间：2025-07-09
- 摘要：Thermodynamic phase equilibrium model was adopted to study the low temperature performance of hydrogenated biodiesel-ethanol-diesel ternary blend, and the crystalli-ation point and crystalli-ation quantity were calculated. Furthermore, the effect of ethanol on the low temperature performance of hydrogenated biodiesel-diesel binary blend was also investigated by comparing the crystalli-ation points and crystalli-ation quantities of ternary blend and binary blend. It was revealed that compared with hydrogenated biodiesel-diesel binary blends, the crystalli-ation points of hydrogenated biodiesel-ethanol-diesel ternary blends were reduced to varying degrees. To be specific, the crystalli-ation points of PHC5E5, PHC10E10, PHC15E15, PHS5E5, PHS10E10 and PHS15E15 were reduced by 4.5, 5.7, 6.1, 4.3, 5.3 and 6.1 K, respectively, compared with the corresponding binary blends. Various decreases of crystalli-ation quantities for ternary blends at different temperatures were also observed in contra关键词：hydrogenated biodiesel;ethanol;ternary fuel blend;thermodynamic phase equilibrium;low temperature performance206|5|1更新时间：2025-07-09
- 摘要：To improve the efficiency of the shipborne gas turbine and reduce the temperature of exhaust gas, a novel waste heat recovery cycle composed of supercritical carbon dioxide regenerator Brayton cycle and organic flash cycle is proposed, in which the supercritical carbon dioxide recycles the high temperature exhaust gas, and the organic flash cycle recovers the low temperature exhaust gas. Then, thermodynamic analysis of the cycle and optimi-ation of the target function with cyclic net power are conducted. The results show that under the basic conditions, the thermal efficiency and enthalpy efficiency of the gas turbine after the waste heat recovery cycle are up to 50.4% and 68.93%, which is 44% and 43.6% higher than that of the stand-alone gas turbine cycle, respectively. In addition, the largest value of exergy loss is 842.04 kW in the condenser, accounting for 6% of the system total exergy value. When the carbon dioxide compression pressure ratio is larger and the terminal temperature关键词：shipborne gas turbine;waste heat recovery cycle;thermodynamic analysis;optimi-ation236|5|7更新时间：2025-07-09
- 摘要：Coupled with gas-pressure differential equation and gas-state equation, a Hagen-Poiseuille formula-based gas-charging physical model of the hohlraum is established by Matlab. Numerical simulation and analysis are carried out on the helium pressuri-ation in the inertial confinement nuclear fusion process. The results show that the continuous fluid model in the helium filling process can meet the calculation accuracy requirements. The capillary flow capacity has great influence on the pressure and temperature rise in the hohlraum. When the initial temperature of helium is the same, as the capillary flow capacity increases, the gas filling rate is increased. Meanwhile, the gas temperature is raised in the hohlraum. After setting the cold-wall variable power strategy, as the maximum cooling power of the cold wall increases, the filling rate and the temperature in the hohlraum are decreased. Once the maximum cooling power of the cold wall goes up about 0.5 mW, the maximum temperature rise i关键词：helium pressuri-ation;capillary;Hagen-Poiseuille formula;numerical simulation214|5|1更新时间：2025-07-09
- 摘要：To solve the problem that the pressure drop of the system is greatly increased by the traditional fully filled metal foam enhanced tube, a new gradient filling method is simulated. The heat exchanger pipe is filled with two layers of metal foam with different permeabilities in the radial direction. Numerical simulation is conducted to study the flow and heat transfer characteristics of the metal foam filled tubes with gradient permeability. The results show that the heat transfer and flow performances are directly related to the permeability gradient. When the dimensionless permeability gradient is greater than 10, the comprehensive heat transfer performance of the metal foam filled tube with gradient permeability can be improved by 2 times compared with that of the pipe with uniform permeability. However, when the dimensionless permeability gradient is less than 0.1, the comprehensive heat transfer performance is decreased by 27%. In order to achieve better heat transfer performance,关键词：gradient permeability;metal foam;comprehensive heat transfer performance254|5|0更新时间：2025-07-09
- 摘要：To improve the interlayer bonding performance and meet the design requirements of 3D mechanical properties of composite materials, an embedded co-cured stitched damping structure was presented. The fabrication process of the embedded co-cured stitched damping composites was developed. The vulcani-ation temperature and time of the damping material were the same as the curing temperature and time of the resin in the prepreg. The preformed structure was stitched by using an improved lock stitching method, and then the embedded co-cured stitched damping composite specimens were finally prepared in autoclave. Free decay test, interlaminar shear test and tensile test were conducted on the specimens. The results showed that the damping performance and maximum tensile stress were increased but the interlayer bonding performance was decreased with the increase of the stitch length. When the damping layer thickness was 0.1 mm and stitch length was changed, the damping ratio, tensile strength and关键词：stitched damping composite;interlaminar bonding performance;damping performance166|5|3更新时间：2025-07-09
- 摘要：To understand the combustion characteristics of Zhundong coal in the cyclone furnace with liquid slagging, numerical simulation of cyclone combustion process of Zhundong coal was conducted. The heat and mass transfer models were established to solve the thermophysical parameters of the slag film, and the parameters were introduced into the combustion CFD model as the boundary condition. The results show that the calculated flame temperature is consistent with the measured value of thermocouple, and the maximum error is less than 4%. The ash particles larger than 10 -m may collide with the slag film and be adhered to the slag, and the particle deposition can be simplified to a single collision. The slag film thickness is non-uniformly distributed along the cyclone furnace length, and the maximum thickness is about 2 mm. The slag film can be approximated as the flow boundary layer of Newtonian fluid. The slag temperature in the slagging outlet is higher than the temperature correspondin关键词：cyclone combustion;Zhundong coal;heat and mass transfer;liquid slagging;slag capture rate238|5|2更新时间：2025-07-09
- 摘要：The physical vapor deposition(PVD)thin film sensor prepared by ion plating technology and the 2A12-T4 aluminum alloy test piece are investigated. The feasibility of PVD thin film sensor for vibration fatigue crack monitoring of common substrate is verified. Finite element simulation analysis is carried out to determine the location of cracks in the test piece, and the preparation of the PVD film sensor is completed by ion plating technology. Then, the resonance frequency, vibration amplitude and fatigue strength of the test pieces with different surface treatment states are compared. In the significance analysis, it is verified that the process of preparing the PVD film sensor does not exert an obvious impact on the vibration fatigue performance of the common substrate. The preliminary monitoring test of vibration fatigue crack in 2A12-T4 aluminum alloy test piece demonstrates that the monitoring results of the PVD film sensor coincide well with the actual observation results, and the关键词：crack monitoring;physical vapor deposition film;sensor;vibration fatigue213|8|0更新时间：2025-07-09
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