The tip-clearance flow in axial turbomachines is studied using large-eddy simulation with particular emphasis on understanding the unsteady characteristics of the tip-leakage vortical structures and the underlying mechanisms for cavitation-inducing low-pressure fluctuations. Systematic and detailed analysis of the velocity and pressure fields has been made in a linear cascade with a moving end-...

This paper describes two recent applications of aerosol sealing techniques in buildings for improving indoor air quality and reducing energy required for heating, cooling, and ventilation. One application applies a commercially-available duct sealing technology, which has typically been used in single-family applications, to large-building exhaust systems. The initial leakage rates, percent lea...

We study the leakage of air in syringes with Teflon coated rubber stopper and glass barrel. The leakrate depends on interfacial surface roughness, viscoelastic properties elastoplastic coating. measured rates are compared to predictions a simple theory for gas flow, which takes into account both diffusive ballistic multiscale contact mechanics determines probability distribution separations. sh...

The leakage characteristics of the bending-teeth gland, which may be helpful for the fast start and fast stop of the steam turbine, was discussed in this paper by using ANSYS6.1 software. By compared the flow fields in straight-teeth gland and bending-teeth gland, the methods for the bending-teeth gland to decrease the steam leakage was proposed. The results show that, although the leakage of t...

This project aims at using (PD-MCPWM) Phase disposition multi carrier pulse width modulation technique to reduce leakage current in a transformerless cascaded multilevel inverter for PV systems. Advantages of transformerless PV inverter topology is as follows, simple structure, low weight and provides higher efficiency , but however this topology provides a path for the leakage current to flow ...

We report a method for addressing gas leakage in micromachined valves. The valves used for evaluating the proposed concept utilize a silicon valve seat that is bonded to a glass substrate and actuated by a piezoelectric stack, all of which are assembled within a ceramic package. The sealing method uses the capillary forces of a liquid sealant on the valve seat to reduce gas leakage below measur...

Indwelling bladder catheter-associated leakage, or catheter bypassing, is a frequently experienced problem, necessitating a carefully planned intervention. Once a bladder catheter is in place, urine may flow intermittently between the catheter shaft and the urethra mucosa, or from around the catheter when inserted suprapubically. A review of the literature identified several reasons for this le...