In this study, the influence of stress level on the creep fracture of notched wood was examined experimentally at room temperature. The material used for the experiment was western hemlock. Crack opening displacement, acoustic emission, crack progagation, temperature and humidity for the stress levels of 50- 75% of Mode I fracture stress. In the condition of this study, creep fracture of notched western hemlock was not occurred under 50% stress level of Mode l fracture stress.

View full abstract

This paper describes a numerical simulation of three dimensional flow in a screw-type centrifugal pump with tip clearance at different now rates (Q/Q_d=1.0, 0.8, 0.6). A reliable commercial three-dimensional Navier-Stokes code with a standard k-ε turbulence model, CFX-TASCflow, was used for this study. The Transient Sliding Interface condition was used to catch up the interaction between the impeller and volute casing. At the design point the calculated now was reasonable and they agreed well with the experimental results. However, the simulation results show that the flow pattern is changed by the flow rate and the influence of tip clearance is remarkable in this pump type.

View full abstract