The effect of metabolic heat generation on the freezing of biological tissue has been studied. Quasi-steady approximation is used to solve the Pennes bioheat equation in tissues. Temperature profile and motion of freezing interfaces are obtained for different values of metabolic heat generation. It is observed that metabolism has a significant effect on freezing of biological tissues during cry...

In classical equilibrium thermodynamics description, ambiguities exist in terms of pinpointing external and internal irreversibilities in overall entropy generation prediction, as a system undergoes a thermodynamic process. The present work attempts to bridge this gap between classical thermodynamics-based irreversibility predictions and finite time heat transfer analysis. By choosing a model p...

The Earth’s surface processes are predominantly controlled by the interaction between the Earth’s internal heat and solar radiation. Surface heat-flow measurements reflect the increase in temperature with depth, which results in flow of the Earth’s internal heat from the core, through the mantle, to the surface. Heat-flow is highest in volcanically active regions and is lowest near oceanic tren...

This paper presents the theoretical methodology, conceptual demonstration, and validation of a fully automated computer program for the inverse design and optimization of internal convectively cooled three-dimensional axial gas turbine blades. A parametric computer model of the three-dimensional internal cooling network was developed, including the automatic generation of computational grids. A...

The Stirling cycle engine is gaining increasing attention in the current energy market as a clean, quiet and versatile prime mover for use in such situations as solar thermal generation, micro cogeneration and other micro distributed generation situations. A theoretical Stirling cycle engine model is developed. Using a theoretical decoupled engine configuration in which working space swept volu...

The paper presents two designs of combined prismatic-parabola-cylindrical stationary concentrators. They reach 8.4X and 10.4X concentration levels for nonsymmetrical and symmetrical concentrators correspondingly and can be used with solar cells for electricity and heat generation. ©2010 Optical Society of America OCIS codes: (220.1770) Concentrators; (220.4298) Nonimaging optics; (220.2740) Geo...

The performance of the two types of vapor-injection (VI) cycles in a heat pump system is compared. The vaporinjection cycle using an internal heat exchanger (IHX) has a choice to select the branching point of the injection stream. The two VI cycles are different in terms of branching points of the injection stream. Different branching points of the injection stream influence the heating capacit...

Theoretical studies have shown that the issue of rupture modes has important implications for fault constitutive laws, stress conditions on faults, energy partition and heat generation during earthquakes, scaling laws, and spatiotemporal complexity of fault slip. Early theoretical models treated earthquakes as crack-like ruptures, but seismic inversions indicate that earthquake ruptures may pro...

A liquid piston concept is proposed to improve the efficiency of gas compression and expansion. Because a liquid can conform to an irregular chamber volume, the surface area to volume ratio in the gas chamber can be maximized using a liquid piston. This creates near-isothermal operation, which minimizes energy lost to heat generation. A liquid piston eliminates gas leakage and replaces sliding ...

The study of boundary layer flow and heat transfer of an electrically conducting visco-elastic second grade fluid in a porous medium past a stretching sheet is conducting with power law surface temperature or power law surface heat flux. The flow in boundary layer is considered to be generated solely by the linear stretching of the boundary sheet adjacent to porous medium in a magnetic field wi...