## Geometry And Numerical Grids

A schematic diagram of the geometry is shown in Figure 2.1. It has a rectangular cross section with channel aspect ratio AR 4 1. Two of the four side walls, in the rotational direction, are denoted as the leading and trailing surfaces, respectively, while the other two side walls are denoted as the top and bottom surfaces. The channel hydraulic diameter, Dh, is 0.8 in (2.03 cm). The distance from the inlet of the channel to the axis of rotation (Y-axis) is given by Rr Dh 20.0 and the length of...

## 2 Description Of Problem

A schematic diagram of the geometry is shown in Figure 3.1. It has a rectangular cross section with channel aspect ratio, AR, of 4 1. Two geometries are investigated, one with smooth walls (Figure 3.1a) and the other one with ribs (Figure 3.1b). Two of the four side walls, in the rotational direction, are denoted as the leading and trailing surfaces, respectively, while the other two side walls are denoted as the top and bottom surfaces. The channel hydraulic diameter, Dh, is 0.8 in (2.03 cm)....

## Hot Streaks with the Nozzle Guide Vane and Endwall

Bogard, University of Texas-Austin, Principal Investigator Karen A. Thole, Virginia Tech, Co-principal Investigator Sean Jenkins and Krishnakumar Varadarajan, University of Texas, Graduate Researchers and Severin G. Kempf and Daniel G. Knost, Virginia Tech, Graduate Researchers Contract Number 01-01-SR092 Clemson University Research Foundation South Carolina Energy Research and Developement Center Clemson University Clemson, SC 29634-5702 This report was prepared with the support of...

## 61 Turbine research facility modifications performed for the specific research program

The Pennsylvania State University currently operates a highly loaded axial flow turbine stage for aerodynamic and heat transfer research. The fully operational facility is of large-scale low-speed nature with modern turbine design attributes. The Axial Flow Turbine Research Facility (AFTRF) is an open circuit facility 91.4 cm in diameter and a hub to tip radius of 0.73, with advanced axial turbine blading configurations as designed by GE (Evendale). The facility consists of a large bellmouth...

## 322 Surface flow near the endwall with no tip clearance

The surface flow visualizations without tip clearance on the pressure, suction, and endwall surfaces are shown in fig. 3.6. The incoming flow is from left to right for the side surfaces with the mid-span at the bottom. The endwall surface flow pattern is shown in fig. 3.6(a). The incoming turbulent boundary layer (shown by the arrow), blocked by the blade leading edge, splits around the saddle point A1 and lifts up along the separation curves S2p and S2s to form the pressure and the suction leg...

## 51 Description of the moving wall apparatus

The moving wall apparatus used for simulating rotation of the blades against the stationary casing in a turbine consists of a 2kW 3-phase induction motor, a rubber belt, three rollers on which the moving wall rotates, and two pitch pulleys which transmit power from the motor to the belt. The whole apparatus rests on an aluminium base that fits on to the top wall of the linear cascade section. The moving wall uses a belt made of N-8 Sampla synthetic rubber that is placed flush with the inner top...

## Goals For Next Reporting Period

1) Conduct Phase III experiments with non-zero pressure gradients. 2) Prepare all required parts and instrumentation for Phase IV testing in the AFRL Turbine Research Facility. 3) Extend the validation of the discrete-element roughness model for heat transfer capability (Stanton number) using the results of Phase II and Phase III. During the past six months, two documents have been generated (one by AFIT and one by MSU) which give a comprehensive summary of the experimental and computational...

## Info

The subscripts R, Tu, and RTu represent cf measurements with roughness only, turbulence only, and the two effects combined respectively. Identical expressions can be written for St as well. Figures 16a-d contain these measures (for cf and St) for all 6 samples in Table 1 at the two elevated Tu levels. In all four figures, the additive predicted effects are less than the synergistic (or actual combined) effects. The average discrepancy is 2 for the 5 Tu ASt St results (Figure 16c) and roughly 20...

## X

Temperature Profile of Erosion Cone Element from General Pin Expression Requested Experimental Action As mentioned earlier, the experimental skin friction results for the Erosion 2 surface are surprising. The experimental results suggest that that the skin friction coefficient decreases 11.58 from an Rex of 5.5x10s to an Rex of 7.0x 105, while the code prediction decreases negligibly from an Rex of 5.5x105 to an Rex of 7.0x105. The code predictions suggest that the flow has reached...

## List Of References

Bayley, F.J., and Owen, J.M., 1970, The Fluid Dynamics of a Shrouded Disk System With a Radial Outflow of Coolant, ASME Journal of Engineering for Power, Vol. 92, pp. 335-341. Blair, M.F., 1994, Experimental Study of Heat Transfer in a Large-Scale Turbine Rotor Passage, ASME Journal of Turbomachinery, Vol. 116, pp. 1-13. Chew, J.W., 1991, A Theoretical Study Of Ingress For Shrouded Rotating Disk Systems With Radial Outflow, ASME Journal of Turbomachinery, Vol. 113, pp. 91-97. Chew, J.W., Green,...

## References

R., and Rohsenow W. M., 1978, An Investigation of Heat Transfer and Friction For Rib-Roughened Surfaces, International Journal of Heat and Mass Transfer, 21, No. 7, pp. 1143-1156. 2 Han J.C., and Park J. S., 1988, Developing Heat Transfer in Rectangular Channels With Rib Turbulators, International Journal of Heat and Mass Transfer, 31, No. 1, pp. 183-195. 3 Han J. C., Zhang Y. M., and Lee C. P., 1991, Augmented Heat Transfer in Square Channels With Parallel, Crossed,...

## Summary Of Progress

Program Developments This research program is divided into four discrete phases Surface Cataloguing, Flat-plate Model Testing, Computational Modeling and Additional Experimental Parameters, and Model Validation in a Full-scale Test Facility. This semiannual report covers results from the Phase II Flat-plate Model Testing as well as progress made with the Phase III Computational Modeling and Additional Experimental Parameters. Progress made toward Phase IV Model Validation in a Full-scale Test...

## 223Data acquisition system

To measure the naphthalene sublimation depth locally on the naphthalene blade surface, a microcomputer-controlled four-axis automated data acquisition system is used, which is also described by Wang (1997) in detail. The four-axis data acquisition system consists of a four-axis table, a motor-controller (Superior Electric MODULYNX) with four terminals, a signal conditional (Schaevitz ATA-101), a Linear Variable Differential Transformer (LVDT) depth gauge (Schaevitz PCA-200-010 LVDT), a Digital...

## 2

In equation (11), y 0 is the no-slip location. The two terms in the numerator of equation (11) represent the contributions of skin friction on the smooth part of the wall and roughness-element drag. The method used for this study treats any point below the mean hydraulic elevation as flat surface at the mean hydraulic elevation and adds the skin friction associated with the flat surface of the mean hydraulic elevation. The blockage fraction, a, at the mean hydraulic elevation is used in...

## 6 3d Piv Measurements

PIV is a whole field measurement technique that provides quantitative two or three dimensional velocity data over a planar region. The flow is seeded with tracer particles, with the two-dimensional plane of interest illuminated by a laser sheet generated by a timed double pulse of a high-power laser. In the digital PIV technique, CCD cameras are synchronized to the laser for recording images of the particles within the light sheet for both laser pulses. The camera images are divided into...