This paper describes the hardware and operations of the Neutrinos at the Main Injector (NuMI) beam at Fermilab. It elaborates on the design considerations for the beam as a whole and for individual elements. The most important design details of individual components are described. Beam monitoring systems and procedures, including the tuning and alignment of the beam and NuMI longterm performance, are also discussed.

A novel transient measurement technique has been developed for determining the heat transfer characteristics in the presence of film cooling (heat transfer coefficient and adiabatic film-cooling effectiveness). The method is based on a transient heater foil technique, where a non-homogeneous surface heat flux is applied to the test surface. A regression analysis of multiple transient liquid crystal experiments is used to obtain the heat transfer characteristics. The method introduced here has the advantage that the (often not known) heat flux distribution at the surface is not needed for the analysis of the measured data. The method is used to study the influence of several heater foil configurations on a flat plate with film cooling, elucidating the effect of different thermal boundary conditions on film-cooling performance. The obtained data is also compared to results presented in literature and good agreement is found.

Emerging additive manufacturing technology offers many opportunities for improved cooling design in gas turbine components by enabling design of cooling passages and shapes that are not manufacturable with conventional methods. Many combustion components have already taken advantage of these design opportunities however adaptation of this technology in turbine hot gas path components has been slower due to challenges with demanding environment and restriction on material properties obtained from additive manufacturing. This paper represents application of additive manufacturing technology in an F class industrial gas turbine including design, development and validation steps of a 1st stage turbine vane. A systematic design approach was undertaken to examine all aspects of operation and cooling of the component to down-select the appropriate design, material and processing. Detail characterization of multiple relevant material properties such as LCF, fracture toughness and creep was conducted to obtain material data and generate elastic and viscoplastic models for component design. Subsequent microstructural analyses of creep specimen were conducted to evaluate creep mechanism. Cooling design studies and coupon specimen testing were conducted to determine heat transfer and flow characteristics of micro channels used in the airfoil design. Detailed conjugate heat transfer analyses were used to iterate and optimize the cooling design. Once final design requirements were achieved, a number of prototype engine components were manufactured and tested in continuous engine operation for a predetermined duration of more than 6 months. These prototype components were removed from the engine after successful operation for validation purposes. Uniform crystal temperature sensors (UCTS) were used to validate the new cooling design. Destructive microstructural evaluations were performed to determine the impact of in-service operation on additive manufactured material. Details of the design and development steps as well as the results of prototype tests and microstructural evaluations are presented and discussed in this paper. It is demonstrated that with proper considerations of the resulting material properties, adaptation of additive manufacturing technology in turbine components is feasible with a comprehensive development process.

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Transient liquid crystal experiments have been carried out to measure the effectiveness and heat transfer characteristics of leading-edge film cooling for three different film cooling holes configurations at design and off-design incidence angle. The three configurations are based on the same representative leading edge model of a turbine blade, consisting of a symmetrical blunt body with a specific leading edge wedge angle. Film cooling is introduced from two rows of cooling holes, representative of a pressure-side row and a suction-side row. At design incidence, film cooling performances are symmetric. There is a jet lift-off situation and shaped holes significantly improve the film cooling performances because of a better lateral coverage and a reduced coolant momentum at the hole exit. At 5° off-design incidence angle, on the suction side, the situation is similar to that of a 0° incidence but with higher film cooling performances due to a reduced local blowing ratio. At 5° incidence on the pressure side, a beneficial interaction between the jets of the pressure side row appears. For middle and high blowing ratio, the film cooling performances are also better than 0° incidence. At 5° incidence on the pressure side, shaped holes also improve the film cooling performances in comparison to cylindrical holes.