Showing papers by "Avram Bar-Cohen published in 2001"

Method and apparatus for converting dissipated heat to work energy

Abstract: A method for converting low temperature dissipated heat to other useful energy and apparatus therefor. Heat energy is transferred to a shape memory alloy using natural conduction of the heat. The kinetic energy of the shape memory alloy resulting from cyclic temperature variations is transferred to another type of energy such as electrical energy.

Design for manufacturability of SISE parallel plate forced convection heat sinks

Abstract: The study reported herein extends a previously reported "design for manufacturability" methodology, to forced convection cooled rectangular plate heat sinks. Using a well validated analytical model, the thermofluid performance of the side-inlet-side-exit (SISE) heat sink has been characterized, parametric optimization carried out, and the maximum heat transfer capabilities for a range of operating points has been determined. A least-material optimization has been performed to achieve optimal material use. The analysis indicates the least-material design to provide significant mass savings for a moderate penalty in thermal performance. Empirical criteria for manufacturability obtained from several heat sink manufacturers lead to qualitative guidelines.

Catheter with thermal sensor for detection of vulnerable plaque

Abstract: Methods and devices for detecting vulnerable plaque within a blood vessel are disclosed. An elongate medical device in accordance with the present invention includes an elongate shaft having a proximal end and a distal end. A substrate is fixed to the elongate shaft proximate the distal end thereof, and a plurality of sensors are disposed on the substrate. Each sensor is preferably coupled to a switching device. The switching devices are preferably disposed on the substrate.

Bypass effect in high performance heat sinks

Abstract: Studies using commercial computational fluid dynamics software, running on a supercomputer, were carried out to investigate the effects of fin density, inlet duct velocity, and clearance area ratio, on the extent of flowbypass and its impact on the thermal performance of the heat sink. Flow bypass was found to increase with increasing fin density and clearance, while remaining relatively insensitive to inlet duct velocity. An optimum geometry, for a fixed inlet duct velocity, bypass clearance, fixed heat sink volume, and constant thickness, was determined.