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In order to grasp the effect of diamond trip geometries on boundary layer transition of hypersonic inlet, an experiment at Mach number 6 in a hypersonic wind tunnel was performed for a hypersonic inlet. The heat transfers at the inlet wall were measured through the infrared thermography. The transition region was judged by the comparison of heat transfer between experiment and computation. Ten diamond forced transition trips were designed according to Modern Design of Experiments. The experimental results shown that the effect order of trip geometries on transition region were the trip height, distance between diamond elements and diagonal length of diamond element from the largest to the smallest. Transition region moved forward to the model tip with increasing trip height or trip length, or with decreasing distance between diamond elements, or with increasing diagonal length of element. The optimized configuration was obtained for diamond forced-transition trip when the optimization object was transitio...

An emittance scanner named Electric‐Sweep Scanner had been designed and fabricated in IMP. And it has been set up on the LECR3 beam line for the ion beam quality study. With some development, the ESS system has become a relatively dependable and reliable emittance scanner. Its experiment error is about 10 percent. We have done a lot of experiments of emittance measurement on LECR3 ion source, and have researched the relations between ion beam emittance and the major parameters of ECR ion source. The reliability and accuracy test results are presented in this paper. And the performance analysis is also discussed.

18GHz microwave has been fed to the LECR3 ion source to produce intense highly charged ion beams although this ion source was designed for 14.5GHz. Then 1.1 emA Ar8+ and 325 eμA Ar11+ were obtained at 18GHz. During the source running for atomic physics experiment, some higher charge state ion beams such as Ar17+ and Ar18+ were detected and have been validated by atomic physics method. Furthermore, a few special gases, e.g. SiH4 and SF6, were tested on LECR3 ion source to produce required ion beams to satisfy the requirements of atomic physics experiments.

A high performance all permanent Electron Cyclotron Resonance Ion Source (ECRIS) LAPECR2 (Lanzhou All Permanent ECR ion source No. 2) has been under construction in IMP for one year. This ECRIS is running at 14.5GHz. The magnetic field configuration is designed according to the famous magnetic scaling laws: Binj = 1.4T (2.2T with an iron plug at the injection side), Bex1 = 1.1T, Bmin = 0.43T and Brad = 1.2T. According to the final design, the source body is φ650mm×560mm in dimension and about 900kg in weight. The source turns out to be the largest all permanent ECRIS in the world. To fabricate such an ion source is really very difficult, however we have succeeded in overcoming the many difficulties and the source has been set up recently. In this article, the typical parameters of the constructed ion source are presented.

Two new space charge compensation methods developed in IMP are discussed in this paper. There are negative high voltage electrode method (NHVEM) and electronegative charge gas method (EGM). Some valuable experimental data have been achieved, especially using electronegative gas method in O6+ and O7+ dramatic and stable increasing of ion current was observed.

The stripping mode for production of multi‐charged radioactive ion beams is discussed, and its advantages are also discussed. A 2.45 GHz ECRIS serving as the primary ion source was designed for production of singly charged radioactive ion beams. This source is compact, reliable, and economical. The magnetic field of the source provided by two permanent magnet rings has been calculated with POISSON code. Additionally, the structure of the source is presented.

With the development of Electron Cyclotron Resonance Ion Source (ECRIS), very high performance ECRIS nowadays have been set up one by one around the world, such as the GTS in Grenoble, SERSE in Catania, LECR3 in Lanzhou and etc, which can produce very intense Multiply Charged Ion (MCI) beam. But till now, the study of the extracted MCI beam from an ECRIS remains open. In this article, we present a theoretical and experimental study of the extracted MCI beam. In the theoretical part, the influences of the extraction system on the extracted ion beam quality are mainly analyzed. The aspects that have influences on the extracted ion beam quality have been analyzed. With the instruction of the analysis, the PBGUNS code is used to simulate the influences of some important aspects concerning the extraction system. The influences of the extraction system geometry design, magnetic field, and the space charge effect will be detailedly presented in this article. In the experimental part, with an Electric‐Sweep Scanner (ESS) emittance detection system, the influences on the extracted ion beam emittance of some typical parameters of ECRIS have been researched, such as the injected RF power, the RF frequency, the magnetic field and etc. The obtained results and the corresponding explanations are presented. Some of the results are well in accord with some empirical laws, but some other results seem to be disputed.

There are two Electron Cyclotron Resonance (ECR) ion sources in operation at the axial injection beam line of HIRFL (Heavy Ion Research Facility in Lanzhou). In most cases, the IMP 14.5 GHz ECR ion source is operated for the cyclotron to achieve intense beams. Intense beams of highly charged gaseous and metallic ions could be produced by the ECR ion source. A particular emphasis has been focused on the production of metallic ion beams recently. Metallic ion beams of Ca, Mg, Fe, Ni and Pb were tested with the IMP 14.5 GHz ECR ion source to improve beam intensities and long-term stability considering cyclotron operation. The stable beams of 60 eμA of 24Mg7+, 130 eμA of 40Ca11+, 45 eμA of 56Fe11+, 25 eμA of 58Ni10+ and 17 eμA of Pb27+ were successfully produced. A new ECR ion source, an upgraded version of the IMP 14.5 GHz ECR ion source but with double rf frequency heating (10 GHz+14.5 GHz), is under commissioning. To satisfy the requirements of the heavy ion cooling storage ring which is under construction...

Electron Cyclotron Heating experiments have been performed on the TEXT tokamak using Varian gyrotron. Some degradation of electron energy confinement is observed for sawtoothing and non‐sawtoothing discharges. Sharp electron temperature profiles are produced in high‐q discharges by extremely localized ECH power deposition. (AIP)