In the present study, the Darrieus-type cross-flow water turbines are simulated using shear stress transport (SST) k–ω turbulent model. Two-dimensional simulation is done using Fluent 17.1 software by varying the tip speed ratio and number of blades. Sliding mesh technique is adopted to capture the variation in flow field. It is observed that the increment in the tip speed ratio tends to increase the power coefficient initially and then decrease. Maximum power coefficient is at a tip speed ratio of 2.327. Also, for lower tip speed ratio four-bladed turbine gives maximum efficiency, whereas for higher tip speed ratio three-bladed turbine gives maximum efficiency. Also, it is found that the torque ripple factor decreases with the increase in solidity except at a tip speed ratio of 1.1636. The turbine with three blades and ω = 80 rpm is selected as the optimized one.