The impulse sources are heat impulses or force impulses lengthways the arrangements. They are represented mathematically by Delta functions and Dirac impulses of finite duration. Conventional fitting conditions are compared hereby. The successive time integration of the PDE provides a system of two equations. A Dirac impulse changes into a Ramp function this way and the Delta function becomes t...

Presented in this paper is a continuous-time mathematical formulation for optimization of heat integrated batch chemical plants. This formulation is applicable to both multipurpose and multiproduct facilities in which opportunities for direct heat integration exist. It is assumed that thermal driving forces and heat duties between operations identified as potential heat integration candidates a...

This paper compares the results of simulations and measurements of evapotranspiration from cultivated fields in Middle Europe. The modelling system THESEUS (i.e. toolbox for hydro-ecological simulation and evaluation utilities) from Wegehenkel (1997a, 2000) was used in this study. Evapotranspiration was also calculated from the latent heat flux density (LE) measured using a modified Bowen ratio...

The efficient operation of existing plants in the process industry requires their analysis through simulation together with power and heat integration by retrofitting. Pinch Analysis (PA) is a classical procedure to achieve this goal. Yet, a further integration can be obtained reducing the entropy generated in the chemical processes. Ammonia, important as raw material in many process industries...

We construct space-time Petrov–Galerkin discretizations of the heat equation on an unbounded temporal interval, either right-unbounded or left-unbounded. The discrete trial and test spaces are defined using Laguerre polynomials in time and are shown to satisfy the discrete inf-sup condition. Numerical examples are provided.

The evaluation of the singular and hypersingular integrals that appear in three-dimensional boundary element formulations for heat diffusion, in the frequency domain, is presented in analytical form. This improves computational efficiency and accuracy. Numerical integrations using existing techniques based on standard Gaussian integration schemes that incorporate an enormous amount of sampling ...

The aim of this paper is to briefly recall heat transfer modes and explain their integration within a software dedicated to building simulation (CODYRUN). Detailed elements of the validation of this software are presented and two applications are finally discussed. One concerns the modeling of a flat plate air collector and the second focuses on the modeling of Trombe solar walls. In each case,...

This semester project follows a previous project at LENI-EPFL [10] and aims at nding the best optimization approach in terms of Heat Pump integration in industrial processes. The MultiObjectiveOptimization method chosen seeks the minimum of both operating and investment costs related to HP purchase. Di erent optimization approaches are tested in order to nd the best solution in terms of feasibi...

To maximize the system-level heat integration, three retrofit concepts of waste heat recovery via organic Rankine cycle (ORC), in-depth boiler-turbine integration, and coupling of both are proposed, analyzed and comprehensively compared in terms of thermodynamic and economic performances. For thermodynamic analysis, exergy analysis is employed with grand composite curves illustrated to identify...