Study on Dynamical Evolution of Dense Stellar Systems with Special Purpose Computers.

1991学年博士牧野博士访问了爱丁堡大学，并与dr . david合作，用专用计算机GRAPE开发了一种用于模拟的Hermite集成代码。Heggie, McMillan and Aarseth（剑桥大学）。mcmillan博士访问了东京大学，并与inagaki博士合作将他的星团模拟代码实现到GRAPE- 2a上，该代码比在碰撞引力系统的n体模拟中广泛使用的Aarseth代码更简单，更适合GRAPE。hunquist博士还访问了东京大学，并将他的SPH代码实现到GRAPE-2A。他们确认GRAPE系统适合使用这两种代码。1992学年博士Makino， Hut和Hunquist系统地研究了用于无碰撞引力系统的树代码中的误差。他们发现树代码提供了足够高的精度来模拟重力n体。hachisu博士开发了一个旋涡动力…更多不可压缩流体模拟的代码。他发现GRAPE系统可以极大地加速涡旋动力学模拟和重力n体模拟。1993学年我们在东京大学小叶校区举办了一个关于致密恒星系统的动态演化和专用计算机发展的研讨会，以总结三年合作的成果。我们得出结论，恒星的直接碰撞在密集的恒星系统中起着重要作用。Drs。Hachisu， Ueno和Miyama研究了各种类型的计算流体动力学代码，得出Gudnov型SPH方法最适合于模拟自重力流体的专用计算机的结论。东京大学和国立天文台合作完成了SPH专用计算机的概念设计和详细设计。在1994学年，我们将制作SPH机的测试板，并开始为SPH代码开发专用的LSI。少

Academic Year 1991Dr. Makino visited University of Edinburgh and developed a Hermite integration code for the simulations with the special purpose computer, GRAPE, in collaboration with Drs. Heggie, McMillan, and Aarseth (Cambridge University). This code is simpler and more suitable to GRAPE than the Aarseth code, which has been widely used in the N-body simulations of collisional gravitational systems.Dr.McMillan visited University of Tokyo and implemented his simulation code for stellar cluster to GRAPE-2A in collaboration with Dr.Inagaki. Dr.Hunquist also visited in University of Tokyo and implemented his SPH code to GRAPE-2A. They confirmed that GRAPE systems are suitable to the use of both two codes.Academic Year 1992Drs.Makino, Hut, and Hunquist systematically investigated the error in the tree code, which is used in collisionless gravitational systems. They found the tree code offers an accuracy high enough for gravitational N-body simulations. Dr.Hachisu developed a vortex dyna … More mics code of incompressible fluid simulations. He found that GRAPE systems can greatly accelerate the vortex dynamics simulations as well as gravitational N-body simulations.Academic Year 1993We held a workshop on the dynamical evolution of dense stellar systems and the development of special purpose computers to summarize the results of three-years collaborations in Komaba campus University of Tokyo. We concluded that the direct collision of stars plays an important role in dense stellar systems. Drs.Hachisu, Ueno, and Miyama investigated the various types of computational fluid dynamics codes and concluded that the Gudnov type SPH method is most suitable to the special purpose computers for the simulations of self-gravitational fluid. The conceptual and detailed designs of the special purpose computer for SPH were done in collaboration of University of Tokyo and National Astronomical Observatory. In the academic year 1994, we shall make a test board of SPH machine and start to develop a special purpose LSI for the SPH code. Less