The location of heat transfer pinch point in evaporator is the base of determining operating parameters of organic Rankine cycle (ORC). The physical mathematical model seeking the location of pinch point is established, by which, the temperature variations both of heat source and working fluid with UA can be obtained. Taking heat source with inlet temperature of 160 C as example, the matching p...

this paper aims at studying a trigeneration system, based on an internal combustion engine and a steam ejector refrigeration system. the designed cycle is to generate cooling and heating energies, and supply power simultaneously. the cycle is studied from thermodynamics point of view and for this purpose, the first law of thermodynamics is applied to all components of the cycle. the efficiency ...

This paper aims at studying a trigeneration system, based on an internal combustion engine and a steam ejector refrigeration system. The designed cycle is to generate cooling and heating energies, and supply power simultaneously. The cycle is studied from thermodynamics point of view and for this purpose, the first law of thermodynamics is applied to all components of the cycle. The efficiency ...

In this paper, a new power, heating and hydrogen cogeneration cycle from Sabalan geothermal two wells is proposed and analyzed. In the proposed system, a new double flash cycle and organic Rankine cycle are used for power production. A proton exchange membrane (PEM) is also used for hydrogen production and the domestic water heater is used for heating. The impacts of some design parameters, suc...

in this paper, first a sensitivity analysis of parameters affecting the performance of the steam generator is performed. this process includes the pinch temperature difference and the gas velocity (width of the hrsg) as the operating parameter and geometrical parameters (fin’s thickness, fin’s height, number of fins in each inch, tube transverse pitch) for each pressure parts is carried out, an...

The subcritical Organic Rankine Cycle (ORC) with 28 working fluids for waste heat recovery is discussed in this paper. The effects of the temperature of the waste heat, the critical temperature of working fluids and the pinch temperature difference in the evaporator on the optimal evaporation temperature (OET) of the ORC have been investigated. The second law efficiency of the system is regarde...

Process models using simplified heat exchanger (HE) are often analyzed methods based on derivatives or optimization procedures, where even small numerical errors can cause algorithms to fail. This article explores the use of approximations for calculating pinch temperature and UA-value, including novel high-order polynomial equidistant Chebyshev grids. The results show that mainstream methods, ...

The mathematics of gauge theories lies behind many of the most profound advances in physics in the past 200 years, from Maxwell's theory of electromagnetism to Einstein's theory of general relativity. More recently it has become clear that gauge theories also emerge in condensed matter, a prime example being the spin-ice materials which host an emergent electromagnetic gauge field. In spin-ice,...

in this paper, the application of neural networks for simulation and optimization of the cogeneration systems has been presented. cgam problem, a benchmark in cogeneration systems, is chosen as a casestudy. thermodynamic model includes precise modeling of the whole plant. for simulation of the steadysate behavior, the static neural network is applied. then using dynamic neural network, plant is...

This paper presents a new method to calculate the freshwater target for water using networks with single contaminant. The pinch point is determined by exploiting one of the features of water-pinch-analysis: freshwater is only necessary below the pinch. With the known pinch point, the calculation of the freshwater target becomes very simple, especially for the networks with many streams. The res...