Study 17. Cogeneration (CHP), trigeneration (CCHP) and quadrogeneration (CCHPI) or how much of mathematic is contained in thermal engineering

[ValeryOchkov]

This study describes the methods of calculation of grids – hydraulic and electric. Emphasis on the mathematical basis of solving such problems. Described methods of improving the efficiency of power supply due to the simultaneous production of heat, electricity and cold.

Fig. 17.1 Small boilers on the balcony of an apartment building to heat individual apartments

Fig. 17.1a A centralized system heating and cooling new

Fig. 17.1b A centralized system heating new

Fig. 17.2 Calculation of fuel economy on a CHP gas turbine compared to separate power generation (http://twt.mpei.ac.ru/MCS/Worksheets/PTU/Vol-13.xmcd)

Fig. 17.3 Determination of equivalent fuel economy for district heating with the turbine type T (district heating) compared to separated production of the same amount of electricity and heat (http://twtmas.mpei.ac.ru/mas/Worksheets/ES/Vol-8.mcd)

Fig. 17.4 Search in Google

Fig. 17.5 Interactive computation of NaCl water solution density (http://twt.mpei.ac.ru/MCS/Worksheets/water-chem/NaCl-Water-Solution-t-omega.xmcd)

Fig. 17.6 Access to information about the file URL

Fig. 17.7 Reference in Mathcad 15

Fig. 17.8 Website page displaying physical properties of aqueous solutions of salts (Водная химия)

Fig. 17.9 Example of hydraulic calculations in Mathcad 15

Fig. 17.10 Calculation of the resistance to flow of fluid in the pipe

 

Fig. 17.11 Calculation of pressure difference in the pipe sections

Fig. 17.12 Example of hydraulic calculations in Mathcad Prime

 

Fig. 17.13 Verifying the hydraulic calculation in Mathcad Prime

 

Fig. 17.14 Creating a characteristic curve of fluid flow through the pump vs its head

 

Fig. 17.15. Example of one electrical calculation in Mathcad Prime

Fig. 17.16. The solution of an overdetermined system of linear algebraic equations in Mathcad Prime

 

Fig. 17.17. Analysis and solution of the "classical" system of linear algebraic equations in Mathcad Prime

 

Fig. 17.18 Analysis of wrongly composed linear algebraic equations

 

Fig. 17.19 Graphic analytic solution of underdetermined system of nonlinear algebraic equations

 

Fig. 17.20 Numerical solution of the problem of the optimal size of the cylinder

 

Fig. 17.21 Analytical solution of the problem of the optimal size of the cylinder

Fig. 17.21a Analytical solution of the problem of the optimal size of the cylinder in Maple new

Fig. 17.22 The combination of analytical and graphical methods in solving the problem of the optimum size of the cylinder