Transpose-free Fast Fourier Transform for Turbulence Simulation
  Pseudo-spectral method is one of the most accurate techniques for simulating turbulent flows. Fast Fourier transform (FFT) is an integral part of this method. In this paper, we present a new procedure to compute FFT in which we save operations during interprocess communications by avoiding transpose of the array. As a result, our transpose-free FFT is 15\% to 20\% faster than FFTW. 
A. G. Chatterjee, M. K. Verma, and M. Chaudhuri
cs.MS cs.CE cs.DS physics.comp-ph physics.flu-dyn