Abstract. The directional response of a constant temperature hotwire anemometer to variations in pitch and yaw is reviewed, and a new data reduction technique for obtaining velocity vector data in a steady flow is described. Sequential sampling of the signal as the probe shaft is rotated through 360 ~ provides data to yield a threedimensional velocity vector. Jorgensen's expression was found to be suitable for the data reduction using independently measured pitch and yaw coefficients. Within the range of velocity and flow direction investigated, the velocity magnitude and direction can be determined to within 2% and 2 ~ respectively if the yaw coefficient is neglected. This measurement method is currently being used to determine velocity distributions on the intake-valve/cylinder boundary for different induction system designs.

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Numerous methods exist in the literature for decomposing mathematical programming (MP) problems. The question for the designer wishing to utilize any of these methods is, what (if any) structure exists in a particular problem, and what (if any) decomposition method(s) may be appropriate for the problem at hand. The paper develops a formal methodology, termed Decomposition Analysis, to answer this question. Decomposition of a mathematical programming problem requires identification of linking variables or functions which effect independent optimization problems. Examination of prevalent methods reveals various structures in an MP problem which determine appropriate decomposition methods for a particular problem. An undirected graph representation of the MP problem facilitates rigorous identification of the desired structures that allow decomposition. The representation is the foundation of the methodology to analyze any particular MP problem for its decomposability.

A new measurement method is utilized to determine velocity distributions on the intake-valve/cylinder boundary for different induction system designs. The velocity information is being used to calculate the angular momentum flux and to define local discharge coefficients around the valve periphery. The contribution of local flow direction (effective area) and local flow speed (velocity losses) to the global discharge coefficients is examined. The dependence of the discharge coefficient on the flow direction and mean velocity magnitude provides useful diagnostic data to relate intake port geometry and flow performance. The measurement technique is also described in detail. The directional response of a single hot-wire anemometer is utilized along with sequential sampling of the signal as the probe shaft is rotated through 360 deg. Within the range of velocity and flow direction required, the velocity magnitude and direction can be determined to within 2 percent and 2 deg, respectively.

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