When two rough bodies slide against each other, asperities on the opposing surfaces interact with each other, defining a transient contact and heat conduction problem. We represent each body by a Greenwood and Williamson asperity model with a Gaussian height distribution of identical spherical asperities. The heat transfer during a typical asperity interaction is analyzed, and the results are c...

Triboelectric nanogenerators (TENGs) have attracted significant interest as the alternative source of renewable energy. Their performance is believed to depend on contact force, but its origin yet be established. Herein, we show that lies in real area Ar, probed with novel experiments specifically designed for this purpose. The open circuit voltage Voc, short current Isc and Ar a TENG, having t...

In internal combustion engines, exhaust valve and its seat gain considerable temperature as the hot gases exit through them. So, the rate of heat transfer should be under control. In this study, the contact heat transfer coefficient has been estimated. An experimental study on an Air-Cooled internal combustion engine cylinder head has been considered. Using the measured temperatures of sensors ...

Contact resistance among the components of a polymer exchange membrane fuel cell (PEMFC) has a crucial effect on cell performance. The geometry of the endplate plays an essential role in the contact pressure distribution over the membrane electrode assembly (MEA) and the amount of contact resistance between plates. In this work, the effects of endplate geometry on the contact pressure distribut...

This paper investigates the effect of contact geometry, temperature and displacement amplitude on the fretting behaviour of an aero-turbo oil lubricated cylinder-on-flat contact. To be effective, the lubricant needed both to penetrate the contact and then offer protection. Lubricant penetration into the fretting contact is found to be controlled by two physical parameters, namely (i) the width ...

This paper describes a CFD model of the blast wave and fireball dynamics after high-pressure hydrogen tank rupture in fire open atmosphere. Experiments on tanks with nominal working pressure 35 MPa 70 are used to validate get insights into underlying physical phenomena. Parametric studies performed understand effect different sub-models, numerical methods other parameters, e.g. instantaneous or...

Hydrogen gas has been widely recognized as an environmentally clean and renewable energy fuel, and it provides a way to reduce greenhouse gas and air pollution emission. A great deal of effort has been made to develop new techniques in the field of hydrogen energy, including hydrogen production, storage, and infrastructure. Recently a metallic gasket, which is made of type 316L stainless steel,...

This paper deals with the problem of simulating the behaviour of a mobile robot moving on a terrain along a precomputed nominal path. The nominal path is supposed to be provided by a planner. The purpose of the simulator is to instantiate the nominal path into a complete trajectory, while verifying that a set of constraints is satissed all along the motion. The simulator is based on an iterativ...

Despite the critical role of the Langerhans cells in the induction of contact hypersensitivity reactions, non-Langerhans antigen-presenting cells in already sensitized individuals may play a role in the elicitation phase of a contact hypersensitivity reaction. Following epicutaneous challenge with antigens, the number of CD1+DR+ epidermal Langerhans cells increased in a time-dependent way and, ...