The hot gases produced by the internal combustion engines passes through the exhaust valve and causes high temperatures in the exhaust valve and its seat. To avoid damaging the exhaust valve, heat must be transferred from the valve to its seat during the contact they make at the opening and closing cycle. Heat transfer rate from the exhaust valve to its seat is a function of many factors. One o...

The use of 0.6 vol.% single-walled carbon nanotubes in a poly(ethylene glycol)based dispersion gave a thermal paste that was as effective as solder for improving thermal contacts. A thermal contact conductance of 20 · 10 W m K was attained. An excessive amount of nanotubes (e.g. 1.8 vol.%) degraded the performance, because of conformability loss. The nanotubes were more effective than hexagonal...

Molecular dynamics simulations are utilized to predict the effect of Al-O interaction parameter on the contact angle and thermal interface conductance across aluminum-water interfaces. The impact of the current work is two-fold. First, through comparison with experimental data, refined Leonard-Jones parameters for Al-O are estimated. Second, a range of interaction parameters between Al and wate...

This paper illustrates an application of a technique for predicting the thermal characteristics of a bidirectional thermocycling device for polymerase chain reaction (PCR). The micromilling chamber is oscillated by a servo motor and contacted with different isothermal heating blocks to successfully amplify the DNA templates. Because a comprehensive database of contact resistance factors does no...

Polyol-ester-based carbon black pastes are used to either coat or penetrate flexible graphite, thereby increasing the thermal contact conductance of flexible graphite between copper surfaces. Paste penetration by up to an effective paste thickness (the volume of the penetrated paste divided by the geometric area of the flexible graphite) of 5 lm increases the conductance by up to 350%, 98% and ...

We have experimentally investigated the heat transfer mechanisms at a 90610 nm diameter point contact between a sample and a probe tip of a scanning thermal microscope (SThM). For large heated regions on the sample, air conduction is the dominant tipsample heat transfer mechanism. For micro/nano devices with a submicron localized heated region, the air conduction contribution decreases, whereas...

We describe and demonstrate a new class of devices that enable direct thermal conductance measurements on monocrystalline nanostructures. These are possible through our newly developed techniques for three-dimensional, successive surface nanomachining of GaAs-based heterostructures. Our methods allow the patterning of complex devices comprising electrically insulating, mesoscopic thermal conduc...

Hot tips are used either for characterizing nanostructures by using Scanning Thermal Microscopes or for local heating to assist data writing. The tip-sample thermal interaction involves conduction at solid-solid contact as well as conduction through the ambient gas and through the water meniscus. We analyze those three heat transfer modes with experimental data and modeling. We conclude that th...