In the context of higher-dimensional cosmologies we study the conditions under which adiabatic expansion of the visible external space is possible, when a time-dependent internal space is present. The analysis is based on a reinterpretation of the four-dimensional stress-energy tensor in the presence of the extra dimensions. This modifies the usual adiabatic energy conservation laws for the vis...

A thermodynamic process of power generation has been developed for a gas turbine, a steam turbine, and a compressor, supported by adiabatic expansion or compression processes. Recently, the possible inlet temperature of gas turbines has been increased to 1500°C or more, and the inlet temperature of steam turbines also has been increased to 650°C. At these high-temperature conditions, turbine no...

The frequency-dependent dielectric constant, shear and adiabatic bulk moduli, longitudinal thermal expansion coefficient, and longitudinal specific heat have been measured for two van der Waals glass-forming liquids, tetramethyl-tetraphenyl-trisiloxane (DC704) and 5-polyphenyl-4-ether. Within the experimental uncertainties the loss-peak frequencies of the measured response functions have identi...

We provide an explicit expression for the renormalized expectation value of the stressenergy tensor of a spin-1/2 field in a spatially flat Fridmann-Lemaitre-Robertson-Walker universe. Its computation is based on the extension of the adiabatic regularization method to fermion fields introduced recently in the literature. The tensor is given in terms of UV-finite integrals in momentum space, whi...

This study presents 2-D simulations of a flow-through sudden expansion/contraction micro-channel with the existence obstacles. The bottom wall is maintained at constant flux, while other walls are adiabatic. Rectangular adiabatic obstacles mounted before expansion region on upper and lower channel used. finite element method was used to discretize equations that govern physical model. Results i...