Ceramic matrix composite (CMC) have higher temperature durability and lower density property compared to nickel-based super-alloys which so far have been widely applied to hot section components of aero-engines/gas turbines. One of promising CMC systems, SiC–SiC CMC is able to sustain its mechanical property at higher temperature, though it inherently needs environmental barrier coating (EBC) to avoid oxidation. There are several requirements for EBC. One of such critical requirements is its resistance to particle erosion, whereas this subject has not been well investigated in the past. The present work presents the results of a combined experimental and numerical research to evaluate the erosion characteristics of CMC + EBC material developed by IHI. First, experiments were carried out in an erosion test facility using 50 μm diameter silica as erosion media under typical engine conditions with velocity of 225 m/s, temperature of 1311 K, and impingement angles of 30, 60, and 80 deg. The data displayed brittle erosion mode in that the erosion rate increased with impact angles. Also, it was verified that a typical erosion model, Neilson–Gilchrist model, can reproduce the experimental behavior fairly well if its model constants were properly determined. The numerical method solving particle-laden flow was then applied with the tuned erosion model to compute three dimensional flow field, particle trajectories, and erosion profile around a generic turbine airfoil to assess the erosion characteristics of the proposed CMC + EBC material when applied to airfoil. The trajectories indicated that the particles primarily impacted the airfoil leading edge and the pressure surface. Surface erosion patterns were predicted based on the calculated trajectories and the experimentally based erosion characteristics.

A fluid-solid conjugate solver has been newly developed and applied to an actual engine disk system. Most of the currently available conjugate solvers lack the special thermal modeling for turbomachinery disk system applications. In the present new code, these special models are implemented to expand the applicability of the conjugate method and to reduce the required computational resources. Most of the conjugate analysis work so far were limited to the axisymmetric framework. However, the actual disk system includes several non-axisymmetric components which inevitably affect the local heat transfer phenomena. This paper presents 3D conjugate analysis of a single stage high pressure turbine rotor-stator disk system to assess these three-dimensional effects. The predicted temperatures shows good agreement with measured data. The calculated results revealed the three-dimensional analysis is crucial to predict the correct heat transfer field which is especially important in transient situations.

The demand for cleaner, more efficient energy has driven the motivation for improving the performance standards for gas turbines. Increasing the combustion temperature is one way to get the best possible performance from a gas turbine. One problem associated with increased combustion temperatures is that particles ingested in the fuel and air become more prone to deposition with an increase in turbine inlet temperature. Deposition on aero-engine turbine components caused by sand particle ingestion can impair turbine cooling methods and lead to reduced component life. It is necessary to understand the extent to which particle deposition affects turbine cooling in the leading edge region of the nozzle guide vane where intricate showerhead cooling geometries are utilized. For the current study, wax was used to dynamically simulate multiphase particle deposition on a large scale showerhead cooling geometry. The effects of deposition development, coolant blowing ratio, and particle temperature were tested. Infrared thermography was used to quantify the effects of deposition on cooling effectiveness. Although deposition decreased with an increase in coolant blowing ratio, results showed that reductions in cooling effectiveness caused by deposition increased with an increase in blowing ratio. Results also showed that effectiveness reduction increased with an increase in particle temperature. Reductions in cooling effectiveness reached as high as 36% at M = 1.0.

This paper presents the first experimental and numerical work of film effectiveness performance for a novel film-cooling method with an arrowhead-shaped hole geometry. Experimental results demonstrate that the proposed hole geometry improves the film effectiveness on both suction and pressure surface of a generic turbine airfoil. Film effectiveness data for a row of the holes are compared to that of fan-shaped holes at the same inclination angle of 35 deg to the surface on a large-scale airfoil model at engine representative Reynolds number and Mach number in a high-speed tunnel with moderately elevated temperature mainstream flow. The film effectiveness data are collected using pressure-sensitive paint. Numerical results show that the coolant film with the proposed hole geometry remains well attached to the surface and diffuses in the lateral direction in comparison with the conventional laidback fan-shaped holes for coolant to mainstream blowing ratios of 0.6–3.5.

Experimental and numerical studies were conducted for the development of the integrated impingement and pin-fin cooling configuration. In the development, the spatial arrangements of impingement hole, pin-fin and film cooling (discharge) hole were the main concern. The temperature measurement was performed for different test pieces with various spatial arrangements to clarify the cooling effectiveness variation with the arrangement and the other cooling parameters. Experiments were conducted with 673K hot gas flow and room temperature cooling air. The Reynolds number of gas side flow was 380000 and cooling air Reynolds number was 5000–30000. Test plate surface temperatures were measured using an infrared camera. The cooling effectiveness obtained from the experiment for one specimen was different from that for a specimen that had the same pin density but a different spatial arrangement. So it was confirmed that an arrangement of hole and pin, as well as pin density, was an important parameter. CFD analysis was also conducted to make clear how spatial arrangement affected internal heat transfer characteristics. Pressure losses were also evaluated for each specimen, and total thermal performance was compared. A basic configuration with one pin at the center of a unit area showed the most superior total thermal performance.