The thin aluminum liners with an aspect ratio R/?r 1 have been imploded on the primary test stand(PTS) facility,where R is the outer radius of the liner and ?r is the thickness. The x-ray self-emission images present ...The thin aluminum liners with an aspect ratio R/?r 1 have been imploded on the primary test stand(PTS) facility,where R is the outer radius of the liner and ?r is the thickness. The x-ray self-emission images present azimuthally correlated perturbations in the liner implosions. The experiments show that at-10 ns before the stagnation, the wavelengths of perturbation are about 0.93 mm and 1.67 mm for the small-radius and large-radius liners, respectively. We have utilized the resistive magnetohydrodynamic code PLUTO to study the development of magneto-Rayleigh–Taylor(MRT) instabilities under experimental conditions. The calculated perturbation amplitudes are consistent with the experimental observations very well. We have found that both mode coupling and long implosion distance are responsible for the more developed instabilities in the large-radius liner implosions.展开更多
Pulsed power technology,whereas the electrical energy stored in a relative long period is released in much shorter timescale,is an efficient method to create high energy density physics(HEDP)conditions in laboratory.A...Pulsed power technology,whereas the electrical energy stored in a relative long period is released in much shorter timescale,is an efficient method to create high energy density physics(HEDP)conditions in laboratory.Around the beginning of this century,China Academy of Engineering Physics(CAEP)began to build some experimental facilities for HEDP investigations,among which the Primary Test Stand(PTS),a multi-module pulsed power facility with a nominal current of 10 MA and a current rising time~90 ns,is an important achievement on the roadmap of the electro-magnetically driven inertial confinement fusion(ICF)researches.PTS is the first pulsed power facility beyond 10 TW in China.Therefore,all the technologies have to be demonstrated,and all the engineering issues have to be overcome.In this article,the research outline,key technologies and the preliminary HEDP experiments are reviewed.Prospects on HEDP research on PTS and pulsed power development for the next step are also discussed.展开更多
The type PT-821 PT Pump test stand and type PT-881 injector test stand are a set of special test stands for calibration of PT Pumps and injectors of Cummins engines. Both test stands may be used in conjunction with an...The type PT-821 PT Pump test stand and type PT-881 injector test stand are a set of special test stands for calibration of PT Pumps and injectors of Cummins engines. Both test stands may be used in conjunction with any model of Bosch injection pump test benches for PT Pumps and injector calibration. During PT Pump calibration, the type PT-821 test stand should be used in conjunction with a Bosch injection pump lest bench. The PT Pump to be tested is installed on the Bosch injection pump test bench through a mounting bracket and is driven by the bench shaft. When calibrating PT injectors, both the PT-881 injector test stand and the PT-821 PT Pump test stand should be used in conjunction with a Bosch injection pump test bench, with the PT-881 injector test stand installed on Bosch test bench. The injector to be tested is driven by the Bosch injection pump test bench through a coupling. This paper describes the structure and function of the PT-821 PT Pump test stand and PT-881 injector test stand. Some technical problems arc described in detail.展开更多
In order to assess the effects of tuned mass dampers （TMDs） on wind actions, an aeroelastic model with a scale of 1：60 was constructed. Tests were performed in an atmospheric boundary layer wind tunnel to investiga...In order to assess the effects of tuned mass dampers （TMDs） on wind actions, an aeroelastic model with a scale of 1：60 was constructed. Tests were performed in an atmospheric boundary layer wind tunnel to investigate the buffeting response of the pylon with a TMD fixed by a wire rope instead of a spring. The model was tested under different levels of damping. The experimental and numerical results showed that with the TMD in the optimal condition, the buffeting response was reduced by 47%.展开更多
Fundamental power couplers are crucial components for feeding radio frequency power to accelerating cavities. Couplers must be tested and conditioned on a room-temperature test stand to evaluate and potentially improv...Fundamental power couplers are crucial components for feeding radio frequency power to accelerating cavities. Couplers must be tested and conditioned on a room-temperature test stand to evaluate and potentially improve their performance before being installed in an accelerating cavity. A new test system has been designed and is under construction at the institute of modern physics.For this test system, multiple conditioning modes, including the pulse mode, CW mode, and amplitude-sweeping mode, have been embedded in the low-level radio frequency system of the test stand. All of these conditioning modes can be run manually or automatically. In addition, a novel test cavity is proposed and has been designed, which facilitates non-contact conditioning and a multi-purpose test stand.展开更多
Background: This is the first study to publish the normative reference values for assessment of the level of muscular strength through the “standing long jump” test carried out on a large sample of Macedonian school...Background: This is the first study to publish the normative reference values for assessment of the level of muscular strength through the “standing long jump” test carried out on a large sample of Macedonian school children. The normative values encompass a wide span of years (6 - 18). Methods: The research was realized in a large sample of 12618 school children at the age of 6 to 18 years from Macedonia. The sample was divided in 14 groups, according to chronological age and each age group was divided into two subgroups according to the criteria of gender. For estimation of the morphologic characteristics, the following anthropometric measures have been applied: body height in standing position (cm), body weight (kg), as well as the body mass index (BMI). Children aged 6 or above were invited to take a standing long jump test. Results: Boys show statistically better results in all age categories in the standing long jump test than girls, and these differences become bigger with the increase of age, especially after the 14th year展开更多
Thermal performance is the most important factor in the development of a borehole heat exchanger utilizing geothermal energy.The thermal performance is affected by many different design parameters and different operat...Thermal performance is the most important factor in the development of a borehole heat exchanger utilizing geothermal energy.The thermal performance is affected by many different design parameters and different operating conditions such as bleeding.This eventually determines the operation and cost efficiency of the borehole heat exchanger system.The thermal performance of an open standing column well (SCW) type geothermal heat exchanger was assessed under the influence of bleeding.For this,a thermal response test rig was established with line-source theory.The test rig also had a bleeding function by releasing fluid while taking additional underground water through the heat exchanger.The thermal response test was performed with an additional constant input heat source.Effective thermal conductivity and thermal resistance were obtained from the measured data.From the measurement,the effective thermal conductivity is found to have 1.47 times higher value when bleeding is applied.The thermal resistance also increases by 1.58 times compared to a non-bleeding case.This trend indicates enhanced heat transfer in the SCW type heat exchanger with a bleeding function.Bleeding,therefore,could be an effective method of achieving a high heat transfer rate in the SCW type heat exchanger with sufficient underground water supply.展开更多
In the paper, the variable separation approach, homoclinic test technique and bilinear method are successfullyextended to a (1+1)-dimensional Caudry-Dodd-Gibbon-Sawada-Kortera (CDGSK) system, respectively.Basedon the ...In the paper, the variable separation approach, homoclinic test technique and bilinear method are successfullyextended to a (1+1)-dimensional Caudry-Dodd-Gibbon-Sawada-Kortera (CDGSK) system, respectively.Basedon the derived exact solutions, some significant types of localized excitations such as standing waves, periodic waves,solitary waves are simultaneously derived from the (1+1)-dimensional Caudry-Dodd-Gibbon-Sawada-Kortera systemby entrancing appropriate parameters.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11605013,11775032,11805019,and 11705013)
文摘The thin aluminum liners with an aspect ratio R/?r 1 have been imploded on the primary test stand(PTS) facility,where R is the outer radius of the liner and ?r is the thickness. The x-ray self-emission images present azimuthally correlated perturbations in the liner implosions. The experiments show that at-10 ns before the stagnation, the wavelengths of perturbation are about 0.93 mm and 1.67 mm for the small-radius and large-radius liners, respectively. We have utilized the resistive magnetohydrodynamic code PLUTO to study the development of magneto-Rayleigh–Taylor(MRT) instabilities under experimental conditions. The calculated perturbation amplitudes are consistent with the experimental observations very well. We have found that both mode coupling and long implosion distance are responsible for the more developed instabilities in the large-radius liner implosions.
文摘Pulsed power technology,whereas the electrical energy stored in a relative long period is released in much shorter timescale,is an efficient method to create high energy density physics(HEDP)conditions in laboratory.Around the beginning of this century,China Academy of Engineering Physics(CAEP)began to build some experimental facilities for HEDP investigations,among which the Primary Test Stand(PTS),a multi-module pulsed power facility with a nominal current of 10 MA and a current rising time~90 ns,is an important achievement on the roadmap of the electro-magnetically driven inertial confinement fusion(ICF)researches.PTS is the first pulsed power facility beyond 10 TW in China.Therefore,all the technologies have to be demonstrated,and all the engineering issues have to be overcome.In this article,the research outline,key technologies and the preliminary HEDP experiments are reviewed.Prospects on HEDP research on PTS and pulsed power development for the next step are also discussed.
文摘The type PT-821 PT Pump test stand and type PT-881 injector test stand are a set of special test stands for calibration of PT Pumps and injectors of Cummins engines. Both test stands may be used in conjunction with any model of Bosch injection pump test benches for PT Pumps and injector calibration. During PT Pump calibration, the type PT-821 test stand should be used in conjunction with a Bosch injection pump lest bench. The PT Pump to be tested is installed on the Bosch injection pump test bench through a mounting bracket and is driven by the bench shaft. When calibrating PT injectors, both the PT-881 injector test stand and the PT-821 PT Pump test stand should be used in conjunction with a Bosch injection pump test bench, with the PT-881 injector test stand installed on Bosch test bench. The injector to be tested is driven by the Bosch injection pump test bench through a coupling. This paper describes the structure and function of the PT-821 PT Pump test stand and PT-881 injector test stand. Some technical problems arc described in detail.
基金The National Natural Science Foundation of China (Nos. 50808148 and 90815016)
文摘In order to assess the effects of tuned mass dampers （TMDs） on wind actions, an aeroelastic model with a scale of 1：60 was constructed. Tests were performed in an atmospheric boundary layer wind tunnel to investigate the buffeting response of the pylon with a TMD fixed by a wire rope instead of a spring. The model was tested under different levels of damping. The experimental and numerical results showed that with the TMD in the optimal condition, the buffeting response was reduced by 47%.
基金supported by the National Key Basic Research Program of China(973 Program)(No.2014CB845504)
文摘Fundamental power couplers are crucial components for feeding radio frequency power to accelerating cavities. Couplers must be tested and conditioned on a room-temperature test stand to evaluate and potentially improve their performance before being installed in an accelerating cavity. A new test system has been designed and is under construction at the institute of modern physics.For this test system, multiple conditioning modes, including the pulse mode, CW mode, and amplitude-sweeping mode, have been embedded in the low-level radio frequency system of the test stand. All of these conditioning modes can be run manually or automatically. In addition, a novel test cavity is proposed and has been designed, which facilitates non-contact conditioning and a multi-purpose test stand.
文摘Background: This is the first study to publish the normative reference values for assessment of the level of muscular strength through the “standing long jump” test carried out on a large sample of Macedonian school children. The normative values encompass a wide span of years (6 - 18). Methods: The research was realized in a large sample of 12618 school children at the age of 6 to 18 years from Macedonia. The sample was divided in 14 groups, according to chronological age and each age group was divided into two subgroups according to the criteria of gender. For estimation of the morphologic characteristics, the following anthropometric measures have been applied: body height in standing position (cm), body weight (kg), as well as the body mass index (BMI). Children aged 6 or above were invited to take a standing long jump test. Results: Boys show statistically better results in all age categories in the standing long jump test than girls, and these differences become bigger with the increase of age, especially after the 14th year
基金Project supported by the Second Stage of Brain Korea 21 Projects and Changwon National University in2011-2012
文摘Thermal performance is the most important factor in the development of a borehole heat exchanger utilizing geothermal energy.The thermal performance is affected by many different design parameters and different operating conditions such as bleeding.This eventually determines the operation and cost efficiency of the borehole heat exchanger system.The thermal performance of an open standing column well (SCW) type geothermal heat exchanger was assessed under the influence of bleeding.For this,a thermal response test rig was established with line-source theory.The test rig also had a bleeding function by releasing fluid while taking additional underground water through the heat exchanger.The thermal response test was performed with an additional constant input heat source.Effective thermal conductivity and thermal resistance were obtained from the measured data.From the measurement,the effective thermal conductivity is found to have 1.47 times higher value when bleeding is applied.The thermal resistance also increases by 1.58 times compared to a non-bleeding case.This trend indicates enhanced heat transfer in the SCW type heat exchanger with a bleeding function.Bleeding,therefore,could be an effective method of achieving a high heat transfer rate in the SCW type heat exchanger with sufficient underground water supply.
基金Supported the Natural Science Foundation of Guangdong Province of China under Grant No.10151200501000008 the Special Foundation of Talent Engineering of Guangdong Province+2 种基金the Scientific Research Foundation of Key Discipline of Guangdong Shaoguan University under Grant No.KZ2009001the Natural Science Foundation of Zhejiang Province of China under Grant Nos.Y604106 and Y606181the Foundation of New Century "151 Talent Engineering" of Zhejiang Province
文摘In the paper, the variable separation approach, homoclinic test technique and bilinear method are successfullyextended to a (1+1)-dimensional Caudry-Dodd-Gibbon-Sawada-Kortera (CDGSK) system, respectively.Basedon the derived exact solutions, some significant types of localized excitations such as standing waves, periodic waves,solitary waves are simultaneously derived from the (1+1)-dimensional Caudry-Dodd-Gibbon-Sawada-Kortera systemby entrancing appropriate parameters.
