bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the preparation and influence of alkali metal oxides R2O on properties of microfiber glass with high water resistance
Authors: Hao Xiaotian , Wang Qingjiang , Wang Hailong
Published: January 2020

The microfiber glass with high water resistant was prepared by the centrifugation with synchronous water-repellent atomization spray. The influence of the alkali metal oxide Na2O/(Na2O+K2O) ratio on the fiber forming ability, chemical stability, thermal and acoustical insulation properties of the Si-Ca-Mg-Al-Fe-B multi-glass fiber system was studied by combing with the “mixed alkali effect”. It was found that when the ratio Na2O/(Na2O+K2O)=0.97, the fiber forming ability and chemical stability of the prepared microfiber glass were optimized. The transmission loss and the sound absorption coefficient are distributed at 2000Hz at a maximum of 9.1dB and 0.88. Therefore, under this paper preparation conditions the optimal Na2O and K2O distribution ratio of Si-Ca-Mg-Al-Fe-B multi-glass fiber system is 16wt% and 0.5wt%, respectively. Each prepared fiber is tightly connected together by the surface treatment of the water repellent to form a stable fiber network structure, demonstrating the feasibility of producing high water resistant microfiber glass by the centrifugation with synchronous water-repellent atomization spray in practical production applications.
Performance of Free Space Optical Communication Base on Orbital Angular Momentum with Pointing Errors
Authors: Wang Hubang
Published: January 2020

Due to the misalignment of the receiver, the spiral spectrum appears to be extended when the Laguerre-Gaussian beam is applied to atmospheric laser communication. This paper investigates the spiral spectrum spread of the Laguerre-Gaussian beam in the case of receiver misalignment. The analytical expression of Laguerre-Gaussian spiral spectrum under the influence of alignment error is studied by mathematical derivation and simulation. The results show that the detection probability of the original orbital angular momentum (OAM) state varies with the lateral displacement distance and the inclination angle. The bit error rate and channel capacity of each channel were studied to verify the effects of misalignment in multiple OAM communication systems.
Design of large field of view curved optical system based on ZEMAX
Authors: Zhao Yuanlin , Peng Xiangyang , Chang Shengli , Wu Wuming
Published: January 2020

Structural design solved the problem in the paper that the large field of view and high resolution of the compound eye optical system can not be realized simultaneously. A curved compound eye system including a 3-ring lens group is designed. The compound eye system is divided into two parts: the central sub-eye system and the edge sub-eye system. The edge sub-eye system reduced the complexity of processing because of the same lens group. In the design process, we systematically studied the field of view between the single sub-eye system and the compound eye system, and obtained the arrangement of the sub-eyes. Then, the geometrical model of a single sub-eye system stitching is presented which is based on the conjugate relations between the incident and exit window. The whole field of the compound eye system designed by this method could reach up 79.5°, the angular resolution of the center system is 0.01°, and the angular resolution of the edge system is 0.017°. Compared with traditional single aperture optical system, the image quality of edge field of view is greatly improved, and the ability to acquire the target orientation is improved. Finally, the correctness of the optical system is validated with the optical design software ZEMAX. And this research could further promote the application of compound eye imaging system.
System Design Of An Infrared Dual-band Seeker
Authors: Mao Yan-Kai , Zhao Zhen-Yu
Published: January 2020

Infrared imagine seeker is an important development direction of ground-to-groung ballistic missle terminal guidance technology, but it’s derection probability is vulnerable to target/background characteristic detector performance field of view and other factors. In order to improve the ability of infrared seeker to adapt to complex battlefield environment, a new design principle of infrared dual-band seeker is introduced. The whole system adopts dual band design, and uses image fusion technology to enrich the information difference between target and background features. In addition, the design of large and small dual field of view can further improve the target interception and accurate recognition and tracking ability of seeker. The working principle of infrared seeker is analyzed, and the optical design idea and image fusion method are introduced. Through index analysis and calculation, the infrared seeker meets the system requirements, which can provide reference for future ballistic missle seeker design
Low Noise VCSEL Driver for SERF Atomic Magnetometer
Authors: Wang Feihu , Hu Zhaohui , Liu Xin
Published: January 2020

A new type of VCSEL (Vertical-Cavity Surface-Emitting Laser) which uses Pt1000 as a temperature sensitive component and non-magnetic heating membrane as a temperature actuator is designed for SERF (Spin-Exchange Relation-Free) atomic magnetometer, which can decrease the magnetic interference produced while heating or cooling VCSEL. Therefore a low noise driver for this kind of VCSEL is necessary. A driver for the novel VCSEL is designed in this paper. The output current is adjustable from 0 to 4.5 mA, and RMS (Root Mean Square) noise of current is less than 80 nA. The operating temperature of the VCSEL is adjustable between 30-110 °C and RMS noise of temperature is less than 0.6 mK. So that it can be ensured that the VCSEL outputs a laser with stable optical power and wavelength.
Damage characteristics of VO2 films under nanosecond/picosecond laser
Authors: Lu Yuan , Feng Yunsong , Chen LeiLei , Wu Chang
Published: January 2020

Vanadium dioxide films were prepared by magnetron sputtering method. An experimental apparatus for laser damaging VO2 thin film was set up. Nanosecond laser and picosecond lasers were used to irradiate the thin film. The damage morphology of the thin film under these two kinds of laser was observed by metallographic microscope. Under the action of nanosecond laser, the damage of thin film is mainly thermal damage, which is mainly determined by the energy contained in the laser pulse itself, and the required damage threshold is relatively higher. The zero probability damage threshold of monopulse irradiate the film is about 0.13J/cm2.Under femtosecond laser, the damage of thin film is caused by multi-photon ionization and avalanche ionization, and the damage threshold is relatively lower. The zero probability damage threshold of monopulse irradiate the film is about 10.2m J/cm2.
Study on the effect of storage time on the quality of mutton of different brands by low-field nuclear magnetic resonance
Authors: Yang Fang , Lin Qing , Li Jiping , Huang YuYan , Xu Jianmei
Published: January 2020

Based on low-field magnetic resonance technology, the quality of Hainan Dong goat meat was studied at the molecular level. With the prolongation of storage time, the pH value of Hainan Dong goat meat showed an overall upward trend, and the T22 peak and T23 peak of transverse relaxation gradually shifted to the left. As the storage time prolonged, the transverse relaxation times of the peaks of samples T22 and T23 showed a decreasing trend. The T22 peak area of the water that is not easy to flow in the sample gradually decreases, while the peak area of the free water T23 gradually increases. The non-flowable water in Hainan East Goat meat was converted into free water. At the same time, the correlation between the transverse relaxation time and the pH value of the mutton quality index was analyzed, and the relationship between the quality of the mutton and the change of storage time was obtained. Finally, this paper compares Hainan Dong goat meat and Guangxi goat meat. The results show that the value of the hard-to-flow water T22 of Hainan Dong goat meat is small and the meat quality is tender. This provides data support for Hainan Dong goat meat to become the brand of lamb.
A New Single Pixel Imaging System Based on Paired Rotary Diffraction Plates
Authors: Yang Qi , Yuan Zhihao , Wang Shaowu , Lai Jianjun
Published: January 2020

We present a new single-pixel imaging system based on a paired rotary diffractive plates. Compared with tradition imaging system, our designed single-pixel imaging system contains simple structure and lower computational complexity. Theoretical simulation results show the single-pixel imaging system has the feasibility of thermal object imaging at wavelength λ=10.6μm, therefore which can be applied for SF6 gas imaging.
Effect of nano-TiO2 content on the flexural strength and compressive strength of dry-Mixing CDG-Slag based geopolymer paste
Authors: Wang Kai , Zha Xiaoxiong
Published: January 2020

In this paper, the effects of nano-titanium dioxide (TiO2) content on the 28-day flexural strength and 28-day compressive strength of Completely decomposed granite (CDG) and slag based geopolymer paste was investigated, using the dry-mixing method. The calcium hydroxide, sodium carbonate and solid sodium silicate were used as the alkali activator. The results show that with the increase of nano-titanium dioxide content increasing from 0 to 2.0%, the compressive strength and flexural strength gradually increase. In addition, the surface of geopolymer paste gradually became smooth. What’s more, the geopolymer paste microstructure was characterized by using Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray (EDX) Microanalysis, details of the research process and analysis are presented throughout the paper.
Using Synergy Approach To investigate the developmental trends of Solar Energy
Authors: Su Yi-Huei , Wu Jung-Hua
Published: January 2020

In recent years, electricity generation using solar energy has become a popular trend. At present, the solar energy output value of China, the United States (US), and the European Union (EU28) together account for more than 70% of the total global output value; therefore, these nations have a significant influence on future development of solar energy technologies.

In this study, we analyzed data, including those for patents; key technology; output value; trade surpluses (deficits); research and development (R&D) funds and manpower; energy density, and publications in journals, and collected data related to solar energy use in these countries to analyze trends in its use by applying the synergy theory. The subsystems investigated include the industry, government, and academic, and the study period was 2005–2015. We also integrated resources and linked application statuses to track applications by the considered subsystems.

The following results were obtained at the end of this study:

(1) Development of solar energy use technology has slowed down in the EU28, is growing in China, and has plateaued in the US. In terms of trends in synergy, the EU28 showed growth up to 2013, after which a rapid decline was observed; an overall growth trend was observed in China; and a plateau in the was noted in the US after 2011.

(2) Overall, variations in these trends reduced across the industry subsystems affecting decision-making in companies. Overall investment in research and development (R&D) by the government has plateaued. There appeared to be a growth in the academic subsystems, with the number of studies on solar energy increasing.

(3) Patents and published journal articles indicate that, in the EU28, research on key technology for solar energy use has been dominated by theory. However, in China and the US, research is mainly focused on the application of such technology.

The observed trends for solar energy technologies in the study areas. However, the environment for the solar energy use can change; it is recommended that future research take market considerations into account to better understand the trends in the development of solar energy technologies.
Improve subsequent leaching efficiency and extraction rate of germanium in optical fibre cables with pre-treatment
Authors: Chen Wei-Sheng , Chang Bi-Cheng , Shuai Chih-kang
Published: January 2020

Germanium is an important and rare material which widely used in fibre optic industry, accounting for about 40% of the total germanium product usage. Due to the rarity of germanium, developing an effective recycling process of recovering germanium metal from waste fibre optical cables is significant. Fibre optical cables was arranged to do characteristic analysis, pre-treatment and dissolution in this study. In the characteristic analysis, the content of germanium dioxide in the glass fibre was 0.15%, and the remaining components were all silicon dioxide. In the pre-treatment part, it consists of two steps which are the solvent treatment and roasting. At the solvent treatment step, glass fibre can be separated by acetone with a concentration of more than 50% and ethanol with concentration of more than 75%. At the roasting step, NaOH was used as a roasting additive. Adding 5 molar ratio of NaOH/SiO2 at 500 °C for 2 hours can totally convert the optical fibre into the silicate. After roasting, it could be leaching by dilute H2SO4 and its leaching rate is higher than 99.5%. This study can provide a process to recovery germanium from optical fibre effectively. According to the optimal conditions, the recovery of germanium could be up to 99%.
Recovery of valuable metal from Photovoltaic solar cells through extraction
Authors: Chen Wei-Sheng , Chen Yen-Jung , Yueh Kai-Chieh , Cheng Chii-Pwu , Chang Tien-Chin
Published: January 2020

The installation of PV modules was 97.9GW and the accumulation volume of PV device was 500GW in 2018 According to the research, the accumulation of waste modules will reach to 8600 tons in 2030 as the result of the life expectancy of PV modules. Moreover, Crystalline-Silicon solar panels account for 90% of the waste. This study recycles photovoltaic solar cells by leaching and extraction. According to the analyst, Silicon cells content 90% of Si, 0.7% of Ag, and 9.3% of Al. Silicon cells were leached by 4M nitric acid at 80°C for 4 hours then 3M sodium hydroxide at 70°C for 3 hours, and the leaching efficiency were 99.7% of Ag, and 99.9% of Al, respectively. Leaching process separated Silicon from others metal. Na-Cyanex 272 in kerosene was employed to separate Al from Ag. The efficiency of extraction is 96%. After the process of extraction, 1M hydrochloride acid was employed to strip Al from the organic solvent. The efficiency of stripping is 99.9%. After extraction process, Ag was remained in the aqueous phase and precipitated to AgCl. In conclusion, this study shows the optimal parameters of the leaching steps, extraction steps, precipitation and vaccum concentration to get the product. The recovery of Si and Ag were 99.5% and 98% respectively.
Effect of technology application of NOx removal by O3 on fly ash concentration
Authors: Jianfeng Wang , Lei Gong , Peiqi Liu , Ximing Hu , Yue Zhu
Published: January 2020

An experimental study was carried out on the concentration of dust in flue gas from the outlet of desulphurization system under the conditions of different ammonia and ozone recharge, When the dust samples were dried at different temperatures, the mass concentration of dust was quite different. Analysis of samples by TG-DSC and XPS, It was concluded that the great change in the mass concentration of soot is mainly due to the influence of the combined denitrification process of SNCR and O3 on the composition of the original flue gas. The formation of Soluble salt was carried by droplets in the flue gas and retained on the filter membrane. It led to a great change in the concentration of dust. The main substances of the soluble salt were carbonic acid, ammonium nitrate and calcium nitrate.
Effects of Friction Pressure on Microstructures and Mechanical Properties of Friction Welded T92/Super304H Dissimilar Steel Weld Joints
Authors: Li Debiao , Lu Yuan , Chen Mo , Sun Yaqin , Wang Lining , Ding Cong
Published: January 2020

In this paper, the T92 martensitic steel and the Super304H austenitic steel were welded by continuous drive friction welding technique. The friction welding joints exhibited good mechanical and metallurgical properties. The influence of friction pressure on the microstructures and mechanical properties of T92/Super304H dissimilar steel joints was investigated. With an increase in the friction pressure, the grains in the welding zone and the heat affected zone didn’t grow up and the number of second-phase particles precipitates increased. The Vickers hardness increased and the impact toughness decreased, the tensile fracture and fracture location didn’t change.
Assessment of Creep Rupture Properties of Friction Welded Super304H/T92 Steel Weld Joints
Authors: Lu Yuan , Zhang Jianlong , Li Debiao , Bi Cheng , Sun Fuyang , Yang Yang
Published: January 2020

The T92 martensitic and Super304H austenitic dissimilar steels welded joints were always encountered in the super critical boilers. The isothermal method was used to assess the creep rupture strength of weld joints. With the higher loading stress, the transcrystalline fracture was the rupture mode of creep specimens, and results in forming dimples. With the higher loading stress, the transcrystalline fracture was the rupture mode of creep specimens and results in forming dimples. With the lower loading stress, creep cavities joined each other along the grain boundary, the creep rupture was the rupture mode of creep specimens and results in cleavage rupture.
Design and optimization of mixing structure of fully premixed surface burner
Authors: Yongtang Wang , Hui Wang , Zhenglu Sun , Li Liu , Yunxin Shi , Penghua Qiu , Aihua Dong , Kaixiang Zhao , Hong Liu
Published: January 2020

This paper disassembles a brand of fully premixed surface burners, designs a new type of air-fuel mixing structure through literature survey, and uses Fluent software to simulate the prototype and new type of mixing structure through numerical simulation. The simulation of the mixing was carried out. Through comparative analysis, the relevant structural parameters were changed and the new mixing structure was optimized and verified by numerical simulation. The results show that the new mixing structure proposed in this paper has a better effect on mixing, and some rules affecting the mixing are obtained.
Validation of Unipolar Diffusion Charging Models for Spherical and Agglomerated Nanoparticles
Authors: Su Lipeng , Du Qian , Wen Jiwang , Ou Qisheng , Pui David Y.H. , Gao Jianmin , Dong Peng
Published: January 2020

An ion-jet diffusion charger was used in this study to investigate the diffusion charging of spherical and agglomerated nanoparticles, and validate corresponding theoretical models. Results show that the limiting-sphere model and White’s theory could preferably predict the diffusion charging of spherical particles, compared with other models. As to agglomerated particles, it is affected by primary particle size and sintered morphology to some extent. Especially for loose agglomerate which is point-to-point contact, obviously more charges could be acquired at same mobility diameter in unipolar diffusion charger. In addition, it was validated that all of Chang’s theory, normalized capacitance model and collision kernel model are in good agreement with experiments results. Chang’ theory and normalized capacitance model, however, are more concise and could be used to evaluate diffusion charging of non-spherical particles in real occasions.
Review of flow regime in CFB standpipe and circulation rate measurement
Authors: Yang Zhao , Liu Xuemin , Qi Guoli , Dong Yong
Published: January 2020

The classification and characteristics of flow regimes in a circulating fluidized bed standpipe were briefly described. Based on the flow characteristics, several measuring methods of circulating flow rate in standpipe were introduced, including accumulation method, time-of-descent measurements, particle motion detection method, flowmeter method, and correlation method. Advantages and disadvantages of these methods were compared. It can be seen that at present, all measurement methods have some defects, which need to be further studied and improved.
Study on Agglomeration of Ultrafine Droplet Particles by Acoustic Air-jet Generators
Authors: Wu Lintao , Zhang Guangxue , Huihui Yao , Ma Zhenfang , Chi Zuohe , Liu Shengjia
Published: January 2020

Acoustic agglomeration is a potential technology for fine particle pretreatment, but the high energy consumption restricts its industrial application. In order to develop a reliable sound source with low energy consumption, acoustic air-jet generators with frequencies ranging from 3 kHz to 8 kHz are adopted to study on the agglomeration effect of ultrafine droplet particles. The influences of frequency, flow rate and initial particle concentration on agglomeration efficiency are experimentally investigated. The results show that the acoustic frequency is a crucial factor for the agglomeration efficiency. The agglomeration efficiency of ultrafine droplet particles is higher than 55% at an optimal frequency of 6 kHz. The probability of collision between droplets increases with the increase of the initial mass concentration, which favors aerosol agglomeration. Moreover, it is shown that the sound pressure level increases with the increase of flow rate of compressed air.
Heat Transfer Calculation of Organic Heat medium Heater and Analysis of maximum film temperature
Authors: Hu Hao , Liu lianqiang , Liu Yan , Zhou Liang , Liu Yunzhou
Published: January 2020

Medium hot oil is applied to heat transmission when accurate temperature of process is required and process should be heated homogenously and slowly in petroleum industry. Organic heat medium heater is applied to process whose outlet temperature is below 400°C. Organic heat medium heater is listed as B grade, C grade and D grade as per Boiler Safety Technical Supervision Administration Regulation. Heat transfer calculation is mentioned about Organic heat medium heater and max. Film temperature calculation is also demonstrated in order to explain deterioration of hot oil.
Simulation study of two phase flow in temperature and pressure reducing device
Authors: Xingsheng Lao , Yong Liu , Chunhui Dai , Wujun  , Wei Wang
Published: January 2020

In order to analyze the influence of water spray desuperheating measures on the pressure and flow velocity in the temperature and pressure reducing device, a small temperature and pressure reducing device is taken as the prototype, the grid is divided and the calculation model is established, and the flow field inside the device under different water spray conditions is simulated. The distribution of the vapor-condensate two-phase flow field in the temperature and pressure reducing device shows that the water injection measures have obvious effect of reducing the temperature, and have almost no effect on the two-phase flow pressure and flow rate fluctuation in the device.
The Range and Standards of Yang Dongfang Temporal Water Temperature Variation Angle I . Model Calculation
Authors: Yang Dongfang , Li Haixia , Ren Haoyuan , Manickam Sivakumar , Yang Dong
Published: January 2020

According to the investigation materials about water bodies of Jiaozhou Bay in May, August and October 1979, this paper studies the changing process of water temperature in the surface and bottom waters. The findings show that from May to August and then to October, water temperature in the waters from inside of bay mouth to the outside forms a peak line over the time. From May to August and then to October, water temperature changes from the lowest to the highest and then drops to a relatively higher level. Based on the definition and model of Yang Dongfang temporal water temperature variation angle, the results indicate that in the water bodies of inside, around and outside of bay mouth, the Yang Dongfang temporal water temperature variation angles in the surface layer range in 75.86-78.84°from May to August, and in -70.41--77.28°from August to October. While in the bottom layer, Yang Dongfang temporal water temperature variation angle ranges in 75.47-75.61°from May to August, and in -63.99--71.27°from August to October.
Research and Analysis of Energy Conservation for organic heat medium heater
Authors: Liu Yan , Xi Yanlin , Liang Zhaohui
Published: January 2020

Organic heat medium heater is defined as boiler of B grade, C grade and D grade as per heat load and is inspected by local government. Organic heat medium heater is widely used in finery factory and chemical plant, and a large amount of energy is consumed by heater. Increasing efficiency is important for energy conservation and saving operation cost. Method of saving energy is discussed and method how to operate safely and effectively is also discussed.
Performance analysis of printed circuit heat exchanger for supercritical carbon dioxide and water
Authors: Zhang Huzhong , Cheng Keyong , Huai Xiulan , Guo Jiangfeng
Published: January 2020

Printed circuit heat exchanger could be used as pre-cooler in the supercritical carbon dioxide (S-CO2) Brayton power cycle. Due to the drastic variations of S-CO2 properties in pre-cooler, segmental design method is used to investigate the thermal-hydraulic performance of PCHE. When the heat duty is given, the local heat transfer entropy generation number has extreme value, which appears near the intersection point of the heat capacity flow rates of both sides. In addition, the local and total entropy generation mainly depend on the local and total heat transfer entropy generation, and the flow imbalance increases entropy generation, especially under conditions of the higher local heat capacity flow rate of water.
Numerical simulation of combustion and emission of blast furnace gas boiler
Authors: Ma Xuhui , Zhang Songsong , Yu Hongling , Qi Guoli
Published: January 2020

Taking an 110t/h full-fired blast furnace gas boiler as the research object, the numerical simulation method is used to calculate the combustion process in the furnace. The influence of flow field on combustion is analyzed, and the influence of air preheating temperature and oxygen concentration on combustion and NOx emission is discussed, which provides a theoretical basis for optimal design and reasonable operation of blast furnace gas boiler. The results indicate that with the increase of air preheating temperature and oxygen concentration, the CO consumption rate is increased, the in-furnace maximum temperature and average temperature are increased to different extents, the temperature distribution is basically unchanged, and the NOx concentration at the furnace outlet is also increased. The NOx concentration multiplies as the oxygen concentration increases.
Study on Combustion Characteristics and Kinetics Analysis of Zhundong Lignite
Authors: Wang Guanyu , Li Xianchun , Meng Fanrui , Wang Huanran
Published: January 2020

The high moisture and low calorific value of Zhundong lignite restricts its long-distance transportation and large-scale application. In this paper, the elemental composition changes and combustion characteristics of the upgraded lignite were studied, and then the combustion reaction kinetics of the upgraded lignite was analyzed by the Flynn-Wall-Ozawa (FWO) method. The results show that with the increase of the upgrading temperature, the content of volatiles and water in the coal decrease, which leads to an increase in the proportion of carbon, nitrogen and sulfur, and a decrease in the content of hydrogen and oxygen. The thermogravimetric curve of the upgraded lignite increases between 573K and 673K as the heating rate increases due to the influence of thermal buoyancy and inhalation gain. The burnout index Hj obviously increases with the increase of the heating rate, and the burnout condition of the coal is obviously improved. The apparent activation energy obtained at the same conversion rate and decreases with the increase of the upgrading temperature, which proves that the increase of the upgrading temperature reduces the apparent activation energy of the upgraded lignite.
Prediction and Analysis of Bamboo heating value Near Infrared Spectroscopy Based on Competitive Adaptive Weighted Sampling Algorithm
Authors: Jin Peiwei , Yao Yan , Qiu Qian , Liu Huijun , Liang Xiaoyu , Cai Jinhui
Published: January 2020

China is one of the largest bamboo producers in the world. Bamboo has the characteristics of large biomass and fast growth, which is considered to be an ideal biomass energy source. In order to satisfy the needs of modern biomass conversion processes, there is an urgent need to develop a method for rapidly determining the heating value of bamboo. In this paper, the spectral data of 80 bamboo samples were obtained by Near-Infrared Spectroscopy (NIRS), and then the heating value of bamboo was measured by conventional methods. Through the analysis of bamboo sample data, the Partial Least Squares Regression (PLSR) algorithm, and the Competitive Adaptive Weighted Sampling and PLSR combination (CARS-PLSR) algorithm were used to establish the relationship between spectral data and heating value. The results show that the number of characteristic wavelengths obtained by the CARS algorithm is 24, while the wavelength of the original medium-long wavelength band is 1320, which reduces the number of wavelengths by 98.18%, and greatly reduces the data size. In addition, the selected feature wavelengths can better reflect the key information of the bamboo spectrum, which have a better model effect than the unscreened model. In this study, the heating value index (R2c, R2p, RPD) of the CARS-PLSR model was 0.97, 0.98, and 6.22, respectively. The bamboo heat generated PLSR model was established by using the characteristic wavelength selected by CARS algorithm, which greatly simplified the complexity of the model and improved the predictive ability of the model.
An Energy Efficiency Indicator and Grading of Shell-and-Tube Heat Exchangers
Authors: Chen Kelei , Qi Guoli , Liu Xueming , Zhang Jianfei , Qu Zhiguo
Published: January 2020

The shell-and-tube heat exchanger is the most commonly used heat exchange equipment in the industry. Whether shell-and-tube heat exchangers are energy-saving is of great significance for the efficient using of energy. Therefore, the corresponding evaluation system and index are needed for evaluating the heat transfer process in the shell-and-tube heat exchanger. In this paper, based on Kern method, the energy efficiency evaluation index of shell-and-tube heat exchanger suitable for oil-water working medium is derived. And the relevant database is used to obtain the overall energy efficiency distribution of the industry, which is subject to the normal distribution, finally according to the overall energy efficiency distribution, the energy efficiency of the shell-and-tube heat exchanger is graded.
Theoretical Analysis of Acid Dew Point Temperature and Vapour Condensation Characteristics of the Flue Gas
Authors: Wang Ning , Liu Xuemin , Guan Jian , Qi Guoli , Zhang Jianfei , Zhiguo Qu
Published: January 2020

Based on the gas-liquid phase equilibrium and multi-component diffusion theory, an analytical model for predicting acid dew point temperature and vapour condensation characteristics of flue gas was developed. The effects of components content, ash particle radius, wall temperature, coal-burned type and excess air ratio have been investigated. The results indicated that the acid dew point temperature and vapour condensation rate will increase with both water and sulfuric acid vapour contents increase. Vapours are not prone to condense on the ash particles when the particle radius is less than the corresponding critical condensing radius. The vapour condensation characteristics can be divided into two different stages with the wall temperature varies. The particle radius has a significant influence on the vapour condensation characteristics in the higher temperature stage. The acid dew point temperatures present significant differences for different coal-burned types, and the water vapour condensation rate is more sensitive to excess air ratio compared with the acid condensation rate.
Design-Based Thermal Efficiency Correction Method for Hot Water Boiler
Authors: Lin Wang , Chen Liu , Bing Jin , Yue Gao
Published: January 2020

In the boiler design process, the thermal efficiency of the boiler operating under specified parameters is given in accordance with the design specifications. However, under the actual operating conditions, the specified parameters in the design book cannot be met at the same time. Especially for the hot water boiler, the coal quality component and the deviation of low calorific power, the feed water temperature and the ambient temperature will directly affect the operating efficiency of the boiler. In the current boiler energy efficiency test standards, the test conditions are very demanding. It is required to be the design coal type and it also gives fluctuation ranges for several parameters that affect the boiler operation efficiency. For non-design conditions, the boiler operation condition test method can only be executed referring to the standard. However, the measured efficiency is highly variable. This paper aims to analyze and study several parameters affecting boiler efficiency based on the perspective of boiler design, and give corresponding efficiency correction method to provide reference for the correction of energy efficiency test results under non-design conditions.
Numerical Study on Temperature Uniformity of Regenerative Heating Furnace
Authors: Li Hongtao , Zhao Yashan , Ji Yunguang , Xue Shuqi , Liu Yazhi
Published: January 2020

Using CFD simulation technology, the influence of three kinds of operation modes (air change on the same side mode, cross air change mode and staged air change mode) on the temperature uniformity of regenerative heating furnace was studied. The results show that: 1) in the same side air exchange mode, the high temperature area is easy to form in the middle of the furnace, which makes the local temperature of the billet surface high; 2) in the cross air exchange mode, the high temperature area appears in the middle of the furnace, the heat exchange in the middle of the billet is strong, and the heating speed is fast; 3) in the staged air exchange mode, the high temperature area moves to both ends, and the temperature at both ends of the billet is higher than that in the middle. Therefore, in order to keep the temperature of billet constant, the best operation mode of regenerative heating furnace is alternating operation of cross air change mode and staged air change mode.
Study on Calculation of Flue Gas Temperature at the Exit of Heating Furnace of Oil and Gas Field
Authors: Chen Liu , Lin Wang , Bing Jin
Published: January 2020

It is of significance to ascertain the flue gas temperature at the exit of heating furnace, which lays the foundation of thermodynamic calculation of boiler and its design. This study analyses some normal calculation formulas of the flue gas temperature at the exit of heating furnace of oil and gas field, and makes comparisons of different calculation methods via examples. Appropriate parameters are presented, so as to give guide to the design and calculation of heating furnace of oil and gas field.
Analysis of Influence of Atmospheric Parameter Fluctuation on Condenser Pressure
Authors: Zi Pingyang , Chen Youliang , Hao Jiangang , Xie Daxing
Published: January 2020

The influence of atmospheric temperature, humidity and pressure fluctuation on the condenser pressure is analyzed by numerical simulation. The seasons are mainly divided according to the atmospheric humidity range, and the atmospheric data are classified according to the seasons, and the fluctuation range of atmospheric temperature, humidity and pressure in specific seasons is determined, and a simplified condenser pressure coupling calculation model is established. The hypothetical iterative procedure calculates the condenser pressure value within a certain seasonal range and a certain atmospheric parameter fluctuation range. The results show that the atmospheric temperature fluctuations have a great influence on the pressure of the condenser in the spring and autumn, atmospheric humidity and pressure fluctuations have a great influence on the condenser pressure in summer. The primary and secondary analyses were carried out on several parameters of the atmosphere. The influence of temperature on the pressure of the condenser was 93%, the weight of the humidity was 6.2%, and the weight of the pressure was 0.8%, which provided a basis for optimizing the operation mode of the cold end system.
Numerical Simulation Study on Radiation Section of Dehydrogenation Furnace
Authors: Duan Linlin , Liu Cenfan , Chen Sheng , Ji Fang , Deng Guide
Published: January 2020

The three-dimensional numerical simulation of the radiation section of a dehydrogenation furnace was carried out by CFD, the thermal-structure coupling analysis was performed. The full-scale meshing of the geometric model was used in this paper, the temperature field and flow field of the furnace and the furnace tube were simulated. The thermal radiation values and temperature values of the simulation results were compared with the design values, it shows that the simulated values are in good agreement with the designed values. The corresponding numerical calculation can be performed for half or 4/1 of the geometry under the condition with the geometric symmetry of the furnace and the furnace tube being good. The simulation results can provide a reference for the design and optimization of the dehydrogenation furnace.
Effect of Flow Arrangement On Energy Efficiency Index
Authors: Lu Hongliang , Ren Bin , Tang Xiaoying , Xue Xiaolong , He Aini , Li Zhenhua
Published: January 2020

An energy efficiency index (EEI=k/∇pn) was proposed by Zhang et al to rate the energy saving performance of plate heat exchanger, it was also considered to be independent on the heat transfer area and weakly correlated or not correlated with the flow velocity. However, whether EEI as an ideal index is correlated with the structure such as the flow arrangement or not was important and remained to be confirmed by the theoretical or experimental result. The present work was to analyze EEI for 5 heat exchangers with different flow arrangement: parallel flow, counter flow and combined flow by theoretical method. They all were composed of the same 37 pieces of BP type plate with Nu=0.091Re0.73Ptn, Eu=42400Re−0.545. Their inlet velocities between plates and the inlet temperatures for hot and cold fluid were the same and 5 mathematical models were developed. The EEI took into consideration and weighted quantitatively the heat transferred as well as the pressure drop. The comparison verified that the proposed EEI for 5 heat exchangers were different with each other, but 5 heat exchangers with similar flow arrangement were close to each other, less than 5%.
Research Status and Analysis of Biomass Pyrolysis Gasification Technology
Authors: Wang Zhongwei , Zhang Bing , Qi Guoli
Published: January 2020

This paper analyzes the main methods and principles of biomass thermochemical conversion worldwide, introduces common equipment for biomass pyrolysis and gasification, and discusses the current research and numerical simulation of biomass pyrolysis gasification experiments. This paper also analyzes the application status of biomass pyrolysis gasification technology and summarizes the bottleneck problems encountered so as to preliminarily discuss the ways and methods of using biomass pyrolysis gasification to solve tar problems in the future.
Fuel characteristics and explosiveness analysis of pulverized coal industrial boilers in China
Authors: Wang Zhongwei , Zhang Bing , Qi Guoli
Published: January 2020

Pulverized coal industrial boilers are widely used in China in recent years for high thermal efficiency and suitable for contract energy management, especially the in service amount is growing fast in regions like Shanxi, Gansu, Shandong, Tianjin, Liaoning, Hebei, etc. Considering the existing operational safety issues of pulverized coal fired industrial boiler, this article researched the relationship between fuel characteristics including calorific value, volatile, ash, moisture and powder explosion in order to explore and analysis in service pulverized coal industrial boilers explosiveness.
Mechanical Properties and Deformation Behaviour of ARCH and BCT Lattice Structures Manufactured by Selective Laser Melting
Authors: Ding Ruochen , Du Baorui , Yao Jun , Zheng Huilong , Guo Yumeng , Kang Zhenya
Published: January 2020

In this study, a new lattice structure ARCH is proposed, ARCH lattice structure and traditional lattice structures BCT were fabricated from 316 L stainless steel by SLM. Mechanical properties and deformation behavior of the lattice structures were experimentally investigated. The results show that the ARCH lattice structures have better mechanical property and energy absorption capability than BCT lattice structures. Under the same relative density, the compressive strength and elastic modulus of the ARCH lattice structure is 121.27% and 60.48% higher than the BCT lattice structure, and the ARCH lattice structures have better energy absorption properties than the BCT lattice structures.
Comparison of Sliding Wear Properties of 400 Grade Low Alloy Wear-resistant Steels with Different Microstructure
Authors: Pei YingChao , Xia DianXiu , Cong Liang , Wang XueLin , Wang ShouRen , Wang DongYue
Published: January 2020

Comparative study on sliding friction and wear properties of low alloy wear-resistant steel Hardox400 and NM400 at room temperature using Retc multi-function friction and wear tester. The hardness, microstructure and wear surface morphology of the test steel were compared and analyzed by microhardness tester, optical microscope (OM) and scanning electron microscope (SEM). The results show that the wear mechanism of the two kinds of test steels is mainly manifested as abrasive wear and fatigue wear. The Martensite-Bainite Dual Phase Structure in Hardox400 has a good match of strength and toughness, and the sliding wear performance is better than the NM400 of martensite structure.
Optimization of PC-GTAW Orbital Welding Parameters of AISI 304L Stainless Steel Pipe Using ANOVA and Taguchi Method
Authors: Baskoro A S , Kiswanto G , Widyianto A
Published: January 2020

In the present study, the PC-GTAW orbital welding parameters of AISI 304L stainless steel pipe have been optimized by using ANOVA and Taguchi method. The welding method uses Pulsatile Current-GTAW without added material (autogenous). Peak currents were varied in this study and had the same average current of 100 ± 0.5 amperes. The Taguchi method was applied to search for OBW, DoP and UTS that are optimal and L16 Taguchi’s orthogonal array with two factors, four levels and two replications. S/N ratio with a quality character of larger is better (LB) was used to find the maximum value. The results show that raising the peak current would widen the OBW and deepen the DoP but reduce UTS. The 35-C parameter was the optimal parameter to produce OBW and DoP while the 100-C parameter was the optimal parameter to produce maximum UTS.
Influence of Tools Diameters and Plunge Depth on Mechanical Properties of Micro Friction Stir Spot Welding Materials A1100
Authors: Baskoro A.S. , Riyanto A. , Arifardi M.F. , Rupajati P.
Published: January 2020

Welding on thin aluminum alloy material is still relatively difficult, so that appropriate welding technology is needed to joint the ultra-thin aluminum material. One of the processing welding capable of solving to ultra-thin aluminium is micro friction stir spot welding μFSSW). The micro FSSW process is an adaptation of the FSW process where solid-state processes allow the welding process without changes in the basic characteristics of the workpiece. The purpose of this study was to analyze the effect parameters used in this study are pinless tool diameter and plunge depth on micro FSSW. The material used in this study was A1100 with a thickness of 0.42 mm using lap joint. The welding parameters used in this study are tool diameter and plunge depth, where each parameter has three levels. While the response variables observed were mechanical and fractures properties. To analyze maximum shear strength/load using response surface methodology (RSM). Experimental results and analysis of influence tool diameter and plunge depth on micro-friction stir spot welding μFSSW) analysis show that tool diameter and plunge depth are directly proportional to maximum shear load. Furthermore, the smallest hook defect occurs on the tool diameter 5 mm with plunge depth 500 μm.
A Study on Application of Generative Design System in Manufacturing Process
Authors: Hyunjin Chun
Published: January 2020

The paradigm of manufacturing is changing with the recent era of the fourth industrial revolution. In particular, with the rapid development of artificial intelligence technology, tremendous transformation is welcomed in various areas related to manufacturing. This study concentrated on the changes in manufacturing due to the development of a generative design system. It also analyzed how designers design products through a generative design system based on artificial intelligence. The changes in the design part of the manufacturing process through the creative design are as follows: First, once the designer sets up a rough conceptual design, and then enters the conceptual design into the generative design system, the computer provides with a basic form of design. After AI presents multiple designs, designers choose the appropriate and desirable one. Next artificial intelligence puts forward an optimal material proposal considering its function and economics. And the designer reviews this alternative. After the designer’s review, the computer comes up with a final proposal. Much of the design is done by artificial intelligence. This design method will be universal in the future. Therefore, this study analyzed the direction in which the generative design system would develop in the artificial intelligence era. And the results of this study are to present the theoretical basis of the future product design methodology.
Design and Optimization of Vibration Isolation System for Spacecraft Transport Package Box
Authors: Tao Guo , Guangtong Liu , Jie Zhang , Xinyu Li , Wei Wang , Jinghui Guo
Published: January 2020

The damping effect of vibration isolation system for spacecraft transport package box is directly associated with superior or inferior mechanical environment for spacecraft transportation. In this Article, the design process and program for vibration isolation system for spacecraft transport package box were introduced first; followed by analysis on excitation and response during spacecraft transportation by train; finally, an optimization program of vibration isolation system applicable to current working conditions for transportation was given. The results showed that: the frequency of railway road spectrum excitation was concentrated at 1.8Hz and 6.2Hz, indicating that the current vibration isolation system for package box did not have better damping effect. After reducing first-order inherent frequency by about 3Hz, acceleration root mean square may reduce by 40%.
The Test and Verification Methods for the Transportation Vibration Absorption System of Spacecraft
Authors: Guangtong Liu , Xukai  , Guotao  , Qiang Zhang , Liuzhe
Published: January 2020

The complicated road conditions for the transportation of spacecraft give rise to the need for plenty of running tests so as to validate the performance of the vibration absorption System. According to the principles of subscale test, a research is conducted on the approaches to testing the vibration absorption System for the transportation vibration absorption system of spacecraft. Besides, the subscale model and verification system are designed for the vibration absorption System, and the reliability of the vibration absorption system in transit is validated, which provides a means to conduct effective evaluation of the system for energy efficiency and an approach to the optimization design of it.