Peter The Great Saint-Petersburg Polytechnical University

# Calculation of thermal circuits in the United Cycle

The UnitedCycle program was developed by professors of Polytechnic University as the tool allowing at a certain skill and understanding of physical processes considerably to simplify calculation of thermal schemes of power plants — thermal calculation.

#### Modeling of thermal objects in United Cycle is performed in several stages:

• Determination of baseline data which are completely characterizing each element on the scheme. Usually it is the nominal setting mode, with factory characteristics of the equipment. When you change over the life the equipment settings, the adjustments are made. Typically, these are values of underheatings in heat exchangers.
• Implementation of the scheme of ready-built components. In this case, the scheme itself is usually simplified to the necessary extent. There are often restrictions that are imposed on the parameters of the available data, and assess of their impact on the whole scheme in general.

Calculation of the required mode is different from the nominal (factory one). Thus the model is based on factory parameters and recalculates them for the demanded mode through the standard equations in the heating engineer.

#### Relevance.

In the modern world the release of new details for power with equal competition can not take place without performing mechanical, and thermal aero hydrodynamic model . Almost all turbine manufacturers as well as ancillary equipment are able to predict the behavior of the product in advance in certain predetermined conditions, whether the increase of pressure, temperature, humidity degree, etc. However, using the thermal characteristics of the individual circuit elements which mutually affect each other, it’s impossible to predict the behavior of the thermal power plant with a high degree of accuracy.

In new construction, after performance of a series of calculations in United Cycle is possible:

• Define optimum configuration of all power plant
• Choose optimum configuration of each block
• Identify the limit operating modes and achievable parameters in any point of the thermal scheme.

When using the software product at already existing stations it is possible:

• Identify elements of the station that in case of their replacement or repair will make the greatest efficiency of the entire power plant
• Predict the state of the entire power plant at the set thermal and electric loadings, and thus it will allow defining the prime cost of thermal and electric energy.
• constant monitoring of the organization to identify quickly the characteristics of the equipment which are sharply differing from settlement testifying to emergency operation of work.

All technical calculations, both at new construction, and at operation of the existing objects of power allow us to define fuel consumption, prime cost of energy and as result a payback period of the proposed solutions and actions that in the present circumstances when the share of the developed energy doesn’t grow, the growth of rates is limited and the destiny of PDM is unstable, will allow one companies to make informed decisions and to increase profits, while others will carry permanent losses and undergo hostile takeovers.