Friday, April 18, 2008

Thermodynamic Analysis of Compressed Air Vehicle Propulsion

by : European Fuel Cell Forum

The fist compressed air vehicles were built by Andraud and TessiƩ du Motay in
Paris between 1838 and 1840. Since then the idea has been tried again and
again, but has never reached commercialization. In recent years the French
developer MDI has demonstrated advanced compressed air vehicles. However,
the claimed performance has been questioned by car manufacturers and
automobile expert. Basically, when referred to ambient conditions, the relatively
low energy content of the compressed air in a tank of acceptable volume is
claimed to be insufficient to move even small cars over meaningful distances

On the other hand, another air car developer claims to have driven 184 km on
one 300 Liter filled with air at initially 300 bar pressure. Obviously, there are
issues to be resolved, not by heated debates, but by an analysis of the
thermodynamic processes involved. This is the aim of this study

Download
http://www.efcf.com/reports/E14.pdf

Selected Values of Chemical Thermodynamic Properties

Prepared by David R. Lide.
Introduction
The theoretical framework of thermodynamics was well established by the time NBS was founded, and certain important applications, such as improving the efficiency of steam engines, had been demonstrated. However, the broad application of hermodynamics to the design and control of industrial processes had to await the accumulation and organization of a large amount of experimental data, as well as theoretical contributions from quantum mechanics and statistical mechanics. The appearance of Selected Values of Chemical Thermodynamic Properties [1] in 1952 marked a significant milestone in this process. This book represented the culmination of 20 years of work
by Frederick D. Rossini and coworkers in evaluating and systematizing the data that had appeared in the world literature on thermochemistry.

Download
http://nvl.nist.gov/pub/nistpubs/sp958-lide/093-096.pdf

Thermodynamic Properties of Liquid Alkali Metals Using a Charged Hard, Sphere Reference System

this journal now available and free download able at Chinese journal of physics, written by P. B. Thakor, V. N. Patel, P. N. Gajjar, and A. R. Jani from Department of Physics, Sardar Patel University, Gujarat, India, introduce The Gibbs-Bogoliubov (GB) inequality, the experiment results : Structure of liquid metals,Thermodynamic properties,Pseudopotential method.

abstraction


The Gibbs-Bogoliubov (GB) inequality is used to evaluate the Helmholtz free energy of
liquid alkali metals as a function of temperature. The structural contribution to the Helmholtz free energy is investigated by adopting a charged hard sphere fluid model. A well established single parametric local pseudopotential is applied to describe the electron-ion interaction along with five different local field correction functions viz; Hartree, Taylor, Ichimaru and Utsumi, Farid et al., and Sarkar et al., 6.2% to 51.15% of the influence on the Helmholtz free energy is concluded to be due to these local field correction functions with respect to the static Hartree dielectric function. Very good agreement with experimental results is achieved.
PACS. 61.25.M – Structure of liquid metals.
PACS. 65.50.+m – Thermodynamic properties.
PACS. 71.15.Hx – Pseudopotential method.

Download


http://psroc.phys.ntu.edu.tw/cjp/v40/404.pdf

for other journal you should go to http://PSROC.phys.ntu.edu.tw/cjp

Thursday, April 17, 2008

engineering thermodynamic steam and gas turbine power plant

The gas-turbine operates on the principle of the Brayton cycle, where compressed air is mixed with fuel, and burned under constant pressure conditions. The resulting hot gas is allowed to expand through a turbine to perform work. In a 33% efficient gas-turbine approximately two / thirds of this work is spent compressing the air, the rest is available for other work

download more at
http://www.freestudy.co.uk/thermodynamics/t9109.pdf

at this link you will also can see some thermodynamic calculation for steam and gas turbine.