Turbo-Expander Units on Low Boiling Working Fluids

Autor: V. P. Kliuchinski, A. V. Ovsyannik
Jazyk: ruština
Rok vydání: 2021
Předmět:
Exergy
Thermal efficiency
Materials science
020209 energy
Nuclear engineering
Energy Engineering and Power Technology
02 engineering and technology
thermal waste
products of combustion
Waste heat recovery unit
freon
supercritical parameters
electric energy
020401 chemical engineering
energy saving
Heat exchanger
0202 electrical engineering
electronic engineering
information engineering

0204 chemical engineering
Condenser (heat transfer)
secondary energy resources
Overheating (electricity)
Renewable Energy
Sustainability and the Environment

trigeneration
grassman – shargut diagrams
thermodynamic efficiency
Hydraulic engineering
Engineering (General). Civil engineering (General)
work performed
Nuclear Energy and Engineering
exergy losses
Exergy efficiency
Working fluid
TA1-2040
exergetic analysis
TC1-978
overheating of the working fluid
Zdroj: Izvestiâ Vysših Učebnyh Zavedenij i Ènergetičeskih ob Edinennij SNG. Ènergetika, Vol 64, Iss 1, Pp 65-77 (2021)
ISSN: 2414-0341
1029-7448
Popis: The article examines the possibility of increasing the efficiency of the turbo-expander cycles on low-boiling working fluids using those methods that are used for steam turbines, viz. increasing the parameters of the working fluid before the turbo-expander and using secondary overheating. Thus, four schemes of the turbo-expander cycle are considered: the one without overheating of the low-boiling working fluid, the one with single overheating of low-boiling fluid, the one with double overheating and the one with double overheating at supercritical parameters. All the studied cycles were considered with a heat exchanger at the outlet of the turbo expander, designed to heat the condensate of a low-boiling working fluid formed in the condenser of the turbo expander unit. Cycles inP–hcoordinates were built for the studied schemes. The method of thermodynamic analysis of the studied cycles based on the exergetic efficiency has been developed. The results of the research are presented in the form of Grassman-Shargut diagrams, which show exergy losses in the elements of the studied cycles on a scale, and also show the positive effect of the operation of the turbo-expander cycle in the form of electrical power. The analysis of the obtained results showed that the main losses that have a significant impact on the exergy efficiency are the losses of exergy in the recovery boiler. The increase of parameters of low-boiling working body, and the use of intermediate superheating reduce losses in the waste heat boiler and, consequently, increases exergetic efficiency of turbo-expander cycle. The turbo-expander cycle with double overheating at supercritical parameters of the low-boiling fluid is of the largest exergetic efficiency out of the schemes that have been examined.
Databáze: OpenAIRE