9 research outputs found
Critical phenomena: 150 years since Cagniard de la Tour
Critical phenomena were discovered by Cagniard de la Tour in 1822, who died
150 years ago. In order to mark this anniversary, the context and the early
history of his discovery is reviewed. We then follow with a brief sketch of the
history of critical phenomena, indicating the main lines of development until
the present date.
Os fen\'omenos cr\'{\i}ticos foram descobertos pelo Cagniard de la Tour em
Paris em 1822. Para comemorar os 150 anos da sua morte, o contexto e a
hist\'oria initial da sua descoberta \'e contada. Conseguimos com uma
descri\c{c}\~ao breve da hist\'oria dos fen\'emenos cr\'{\i}ticos, indicando as
linhas principais do desenvolvimento at\'e o presente.Comment: Latex2e, 8 pp, 3 eps figures include
Mathematical Aspects of the Periodic Law
We review different studies of the Periodic Law and the set of chemical
elements from a mathematical point of view. This discussion covers the first
attempts made in the 19th century up to the present day. Mathematics employed
to study the periodic system includes number theory, information theory, order
theory, set theory and topology. Each theory used shows that it is possible to
provide the Periodic Law with a mathematical structure. We also show that it is
possible to study the chemical elements taking advantage of their
phenomenological properties, and that it is not always necessary to reduce the
concept of chemical elements to the quantum atomic concept to be able to find
interpretations for the Periodic Law. Finally, a connection is noted between
the lengths of the periods of the Periodic Law and the philosophical
Pythagorean doctrine.Comment: 20 pages, PDF fil
Research on the influence of fuel gas on energy characteristics of a gas turbine
The purpose of this paper is to study and analyze the gas turbine engine and the thermodynamic cycle of a gas turbine. The article describes the processes of influence of the working fluid composition on the parameters of the main energy gas turbines, depending on the composition of the fuel gas. The calculations of the thermal scheme of a gas turbine, which were made using mathematical modeling, are given. As a result of research on the operation of the GE PG1111 6FA gas turbine installation with various gas compositions, it was established that when the gas turbine is operating on different fuel gases, the engine efficiency changes. The gas turbine efficiency indicators were determined for various operating parameters and fuel composition. The impact of fuel components on the equipment operation is revealed
Study of the work and efficiency improvement of combined-cycle gas turbine plants
The purpose of the paper is to study and analyze the possibility of increasing the power output of a combined-cycle gas turbine (CCGT) unit during the period of positive ambient temperatures. The first task is to analyze the operation of a 110 MW combined-cycle power unit at various ambient temperatures and to obtain alterations in the main CCGT characteristics when the ambient temperature changes. The other task is to study the usage of an absorption refrigeration machine in a CCGT cycle to increase its energy efficiency. Calculations of the thermal scheme of a gas turbine were carried out using mathematical modeling, the steam turbine was calculated based on guidelines. The conducted studies allow to conclude that the use of an absorption refrigeration machine in the cycle of a combined-cycle plant can improve the efficiency of the unit, increasing profits from power generation, and reducing penalties for non-compliance with the load schedule