The Helimak experiment produces a toroidal plasma with a helical magnetic field. A simulation-experiment comparison of turbulence in this device is presented, focusing on parameter regimes in which the turbulence is dominated by interchange modes with k(parallel to) similar or equal to 0. The numerical simulations are based on a two-dimensional electrostatic two-fluid model that evolves the full radial profiles of plasma density, the electric potential, and the electron temperature. The simulation results are compared with the experiment and general agreement is found for the plasma profiles, the autocorrelation functions, the frequency spectra, the cross-correlation functions, and the probability density functions. Some quantitative differences between the simulation and experimental data are also discussed. (C) 2009 American Institute of Physics.