HAPPY NEW YEAR

新年，明けましておめでとうございます．
昨年11月に，Ryzen９9950X3D の新しいPC（写真手前の白いPC）を手に入れ，６年以上前のPC（Threadripper 3990X，奥の壁にくっついている黒いPC）とDSMC法の計算速度比較をしてみました．一つのCoreでの比較では２倍程度の能力でしたが，Core数（thread数）が1/4しかないので，結局，3990Xで二つの計算を同時実行したのとほぼ同じ速度しかありませんでした．６年経過しても，3990XのPCはまだまだ健在です．2026年の今年は，６月までに，円管の乱流速度分布を再現するプログラムの改良版を公開すべく努力しています．最近，PCメモリの高騰が続いていますが，何とか Threadripper 9980X のPCの自作もしたいと考えています．

Happy New Year!
Last November, I acquired a new PC with a Ryzen 9 9950X3D processor (the white PC in the foreground of the photo) and compared the DSMC calculation speed with a PC that’s over six years old (a Threadripper 3990X, the black PC attached to the back wall). While the performance was roughly twice as fast on a single core, the number of cores (threads) was only one-quarter of the original, so the speed was roughly the same as running two calculations simultaneously on the 3990X. Even six years later, my 3990X PC is still going strong. This year, in 2026, I’m working hard to release an improved version of a program that reproduces the turbulent velocity distribution in a circular tube by June. While PC memory prices have been rising recently, I’d also like to build a PC with a Threadripper 9980X.