Abstract: The flux profile of a blowing sand cloud is the reflection of blown sand particles moving in different trajectories.To establish the function of the flux profile requires measuring the blown sand flux at different height.A segmented sampler for wind tunnel study(WITSEG Sampler) has been designed and evaluated in a wind tunnel.The sampler is 60 cm high,and sectioned into 60 openings that can measure the flux profile of a blowing sand cloud within 60 different heights at 1cm interval.Special attention is paid in designing the sampler to its practicability and efficiency.For the conveniences of use the leading edge with inlets,sand chambers and side cover are made removable.To maximize the sampling efficiency the leading edge is made wedge-shaped so that the width of the inlets is 0.5 cm while the width of the chamber is 1.5 cm.Each sand chamber has two screened vents that are connected to a vertical vent to minimize the air pressure inside the sand chamber and maximize its efficiency.Wind tunnel evaluation shows that the sampler is good for aeolian sand.Both the measured flux profile and total flux show a reasonably good agreement with the widely accepted results.It has an overall efficiency of 0.91.The WITSEG sampler that can measure the detailed variation of blown sand flux with height proves to be a good tool for studying the flux profile of a blowing sand cloud.

Key words: aeolian transport, sampler, sampling efficiency, flux profile