Dynamic models of heat exchangers

The article is dedicated to a design of a pilot model of a 60 MW installation, operating according to a new promising compressorless combined cycle. In the course of the study, the weight-size parameters and functional indicators of the main parts of the energy complex were preliminarily determined. The auxiliary components of a compressorless combined cycle unit were selected, such as pumps, heat exchangers, compressors, pipelines and etc. Within a draft elaboration, preliminary weight, size and functional parameters of a turbine unit were defined, solutions were found for two groups of pumping equipment, and a plant prototype was designed. Additionally, the weight and size parameters of the plate heat exchangers were determined and a special design of shell-and-tube heat exchangers was designed to return the heat of combustion products. The results, obtained during the study, make it possible to simulate the behavior (develop dynamic models) of a compressorless combined cycle unit in all operating modes (from start-up to shutdown) under various conditions, as well as to carry out a feasibility study for the creation of such installations.

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Dynamic models for heat exchangers and heat exchanger networks

Computers & Chemical Engineering ◽

10.1016/0098-1354(94)80075-8 ◽

1994 ◽

Vol 18 ◽

pp. S459-S463 ◽

Cited By ~ 28

Author(s):

Knut W. Mathisen ◽

Manfred Morari ◽

Sigurd Skogestad

Keyword(s):

Heat Exchanger ◽

Heat Exchangers ◽

Dynamic Models ◽

Heat Exchanger Networks

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Experimental Study of the Variation Dynamic’s for Air Heat Exchanger

Mokslas - Lietuvos ateitis ◽

10.3846/mla.2017.1047 ◽

2017 ◽

Vol 9 (3) ◽

pp. 297-301

Author(s):

Maryia Marozava ◽

Dzmitry Hryniuk

Keyword(s):

Heat Exchanger ◽

Heat Exchangers ◽

Dynamic Models ◽

Management Systems ◽

Stabilization System ◽

Technological Parameters ◽

Control Loops ◽

The Stability

The development of management systems is assigned one of the leading roles. When solving the problems of regulating the technological parameters, various problems arise. One of such problems is the adjustment of control loops. For some control objects, one-time adjustment of the controller parameters can be made, and then it is periodically refined as necessary. In other objects, the changes occur very quickly, but in a certain range. In the latter case, you should first estimate the range of changes. Then find universal robust settings that will ensure the stability and quality of the stabilization system. Some of such objects are air heat exchangers. The article presents the results of the determination of the heat exchanger dynamics. The limits of the variation of the parameters of the dynamic models are determined. There is a significant nonlinearity in the transfer function of the control channel.

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Determination of creep mechanisms in various silicon carbides via TEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143973 ◽

1986 ◽

Vol 44 ◽

pp. 484-487

Author(s):

C. H. Carter ◽

J. E. Lane ◽

J. Bentley ◽

R. F. Davis

Keyword(s):

Heat Exchangers ◽

Sintered Material ◽

Polycrystalline Material ◽

Chemical Vapor ◽

Graphite Substrate ◽

Second Phase ◽

Reaction Bonding ◽

Creep Mechanisms ◽

Porous Sic

Silicon carbide (SiC) is the generic name for a material which is produced and fabricated by a number of processing routes. One of the three SiC materials investigated at NCSU is Norton Company's NC-430, which is produced by reaction-bonding of Si vapor with a porous SiC host which also contains free C. The Si combines with the free C to form additional SiC and a second phase of free Si. Chemical vapor deposition (CVD) of CH3SiCI3 onto a graphite substrate was employed to produce the second SiC investigated. This process yielded a theoretically dense polycrystalline material with highly oriented grains. The third SiC was a pressureless sintered material (SOHIO Hexoloy) which contains B and excess C as sintering additives. These materials are candidates for applications such as components for gas turbine, adiabatic diesel and sterling engines, recouperators and heat exchangers.

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Monetary policy and the effect of the transfer of oil prices to inflation

Voprosy Ekonomiki ◽

10.32609/0042-8736-2020-8-41-50 ◽

2020 ◽

pp. 41-50

Author(s):

Ph. S. Kartaev ◽

I. D. Medvedev

Keyword(s):

Monetary Policy ◽

Inflation Targeting ◽

Dynamic Models ◽

Oil Prices ◽

Oil Price ◽

Oil Price Shocks ◽

Negative Effects ◽

Price Shocks ◽

Policy Regime ◽

The Impact

The paper examines the impact of oil price shocks on inflation, as well as the impact of the choice of the monetary policy regime on the strength of this influence. We used dynamic models on panel data for the countries of the world for the period from 2000 to 2017. It is shown that mainly the impact of changes in oil prices on inflation is carried out through the channel of exchange rate. The paper demonstrates the influence of the transition to inflation targeting on the nature of the relationship between oil price shocks and inflation. This effect is asymmetrical: during periods of rising oil prices, inflation targeting reduces the effect of the transfer of oil prices, limiting negative effects of shock. During periods of decline in oil prices, this monetary policy regime, in contrast, contributes to a stronger transfer, helping to reduce inflation.

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Borehole Heat Exchangers in aquifers: simulation of the grout material impact

Rendiconti online della Società Geologica Italiana ◽

10.3301/rol.2016.145 ◽

2016 ◽

Vol 41 ◽

pp. 268-271

Author(s):

Luca Alberti ◽

Adriana Angelotti ◽

Matteo Antelmi ◽

Ivana La Licata

Keyword(s):

Heat Exchangers ◽

Borehole Heat Exchangers

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Dramatic efficiency gains through improved heat exchangers: the case of cassava flash drying in Nigeria

Food Chain ◽

10.3362/2046-1887.2015.006 ◽

2015 ◽

Vol 5 (1-2) ◽

pp. 91-104 ◽

Cited By ~ 2

Author(s):

Andrew Marchant ◽

Andrew Graffham ◽

Lateef Sanni ◽

Idowu Adeoya

Keyword(s):

Heat Exchangers ◽

Efficiency Gains ◽

Flash Drying

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Methods of parallel computing for multilevel fuzzy Takagi – Sugeno systems

PROBLEMS IN PROGRAMMING ◽

10.15407/pp2016.02-03.141 ◽

2016 ◽

pp. 141-149

Author(s):

S.V. Yershov ◽

◽

R.М. Ponomarenko ◽

Keyword(s):

Dynamic Models ◽

Fuzzy Inference ◽

Knowledge Bases ◽

Comparative Characteristic ◽

Software Systems ◽

Scientific Papers ◽

Speed Up ◽

Diagnostic Software ◽

Takagi Sugeno

Parallel tiered and dynamic models of the fuzzy inference in expert-diagnostic software systems are considered, which knowledge bases are based on fuzzy rules. Tiered parallel and dynamic fuzzy inference procedures are developed that allow speed up of computations in the software system for evaluating the quality of scientific papers. Evaluations of the effectiveness of parallel tiered and dynamic schemes of computations are constructed with complex dependency graph between blocks of fuzzy Takagi – Sugeno rules. Comparative characteristic of the efficacy of parallel-stacked and dynamic models is carried out.

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