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Mexican and US firms and universities are working together to turn a Mexican-USA truck company, Vilpac, into a world class manufacturing firm. A systems integrated enterprise and manufacturing architecture is enabling the firm to successfully manufacture and sell trucks meeting international standards. The company has increased production by 260 percent, reduced fixed total costs by 26 percent, and increased net profits by 70 percent within 18 months. An IDEF functional model helped Vilpac to identify simplification opportunities. The firm launched three long-term, five medium-term, and 19 short-term projects of high strategic impact. A SIMNET II computer simulation model of the entire fabrication process monitors the load of over 95 machines and follows the work in process of over 1,900 parts. It works under push or pull control environments and predicts daily production accurately. It permits the testing of manufacturing configurations and is being used to design a new plant based on group technology and cell concepts.

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In this paper the turbulence effects are studied for three rotors mounted on the same instrumented hub. Two scaled models of industrial turbines and one open-geometry turbine are considered. The turbulence characteristics are obtained from 2D Laser Doppler Velocimeter measurements and the turbine behaviour is analysed from thrust and torque measurements. Three turbulence intensities and a large range of tip speed ratios and flow velocities are considered. The results are anonymised in order to ensure confidentiality. The rotors have different blade profiles, blade numbers and solidity. The rotor design largely modifies the mean power and thrust coefficients. The turbulence intensity only slightly changes these results but has a larger influence on the fluctuating loads than the different rotor designs. The spectral analysis of the rotor torque and thrust shows that, at low frequencies the load variations are correlated to those of the flow velocity with some differences due to the turbulence intensity levels. The coherences between the loads and the velocity seem to be not affected by the rotor type. At high frequencies, the load variations are correlated to the speed control unit of the scaled model and the rotor design has an impact on the rotational speed and loads coherences.