This thesis reports measurements of fluid particle acceleration in a large Reynolds number turbulent flow. The method for acceleration measurement is direct optical imaging of the positions of tracer particles and extraction of their accelerations from the position as a function of time. In order to meet the stringent imaging requirements for such measurements, we have implemented an ultra high speed imaging system based on silicon strip detectors. These detectors have been designed and optimized for vertex detectors in high energy physics collider experiments. With this system we are able to measure two coordinates of tracer particle positions with a dynamic range of better than 5000:1 and a frame rate of 70,000 frames per second.;Acceleration measurements are performed in a flow between counter-rotating disks from Rlambda = 140 to R lambda = 970. The normalized acceleration variance is found to increase with Reynolds number at the lower Reynolds numbers and becomes nearly constant at the higher Reynolds numbers. This plateau is consistent with the Kolmogorov (1941) prediction. Different acceleration components are found to have about 15% different variance even at the highest Reynolds number. The acceleration probability distribution is found to have strong stretched exponential tails and flatness greater than 50.;An analysis of various sources of sample bias and other systematic errors is performed. Measurements of the acceleration variance as a function of the tracer particle size and fluid density demonstrate that the small tracer particles are acting as fluid particles to within the accuracy of the measurements. Measurements of the acceleration of larger particles provides direct measurement of the forces on particles when they are large enough that they are averaging over the small scale structure of the turbulence.
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