In this study, 2D square lattice photonic crystal bend structure based on high index rods placed in air is designed by removing two cross lines of rods to realize two optical channels. The alteration of transmitted energy in the channels depending on rods radius changes is observed in the simulations. Time domain simulation results obtained by FDTD analyses exhibit that, when transverse magnetic (TM) Gaussian point source is applied from left channel, up to 92% of the incident energy can be channelized into a vertical channel. Variation of rods radius in the corner of bend affects considerable to the magnitude of reflected wave in the source channel and the time delay between the incident and reflected waves. Sensitivity analysis of W1 waveguide bend in a photonic crystal (PhC) is achieved to optimize PhC bend structure frequency response. Results of these numerical optimizations can be used to design novel compact switches and optical sensors. (C) 2012 Elsevier GmbH. All rights reserved.