A5073882325- Thermodynamic and Exergetic Analyses of Power and Cooling Systems
- Refrigeration and Air Conditioning Technologies
- Solar Thermal and Photovoltaic Systems
- Advanced Thermodynamic Systems and Engines
- Advanced Control Systems Optimization
- Heat Transfer and Optimization
- Modeling and Simulation Systems
- Advanced Thermodynamics and Statistical Mechanics
- Heat Transfer and Boiling Studies
- Catalysts for Methane Reforming
- Solar Energy Systems and Technologies
- Adsorption and Cooling Systems
- Integrated Energy Systems Optimization
- Heat transfer and supercritical fluids
- Phase Change Materials Research
- Phase Equilibria and Thermodynamics
- Building Energy and Comfort Optimization
- Photovoltaic System Optimization Techniques
- Industrial Automation and Control Systems
- Membrane Separation Technologies
- Electrocatalysts for Energy Conversion
- Extremum Seeking Control Systems
- Rocket and propulsion systems research
- Greenhouse Technology and Climate Control
- Subcritical and Supercritical Water Processes
University of Liège
2012-2018
This paper presents the results of an on-going project to develop ThermoCycle, open Modelica library for simulation low-capacity thermodynamic cycles and thermal systems.Special attention is paid robustness speed since dynamic simulations are often limited by numerical constraints failures, either during initialization or integration.Furthermore, use complex equations state (EOS) compute properties significantly decreases speed.In this paper, approach adopted in overcome these challenges...
When modeling low capacity energy systems, such as a small size (5–150 kWel) organic Rankine cycle unit, the governing dynamics are mainly concentrated in heat exchangers. As consequence, accuracy and simulation speed of higher level system model depend on exchanger formulation. In particular, thermo-flow systems characterized by evaporation or condensation requires models capable handling phase transitions. To this aim, finite volume (FV) moving boundary (MB) approaches most widely used....
In this paper, the optimal operation of a stationary sub-critical 11 kW el organic Rankine cycle (ORC) unit for waste heat recovery (WHR) applications is investigated, both in terms energy production and safety conditions. Simulation results validated dynamic model ORC power are used to derive correlation evaporating temperature, which maximizes generation range operating This idea further extended using perturbation-based extremum seeking (ES) algorithm identify online temperature....
This paper addresses the issues linked to simulation failures during integration in finite-volume flow models, especially those involving a two-phase state. kind of model is particularly useful when modeling 1D heat exchangers or piping, e.g., thermodynamic cycles phase change. Issues, such as chattering stiff systems, can lead low speed, instabilities and failures. In particular case they are usually discontinuity density derivative between liquid zones. this work, several methods tackle...
Screw-type volumetric expanders have been demonstrated to be a suitable technology for organic Rankine cycle (ORC) systems because of higher overall effectiveness and good part-load behaviour over other positive displacement machines. An 11 kWe single-screw expander (SSE) adapted from an air compressor has tested in ORC test-rig operating with R245fa as working fluid. A total 60 steady-steady points obtained at four different rotational speeds the range between 2000 rpm 3300 rpm. The maximum...
Organic Rankine cycle (ORC) systems are gaining ground as a means of effectively providing sustainable energy. Coupling small-scale ORCs powered by scroll expander-generators with solar thermal collectors and storage can provide combined heat power to underserved rural communities. Simulation such is instrumental in optimizing their control strategy. However, most models developed so far operate at steady-state or focus either on ORC dynamics. In this work, model for the dynamics system...
In this paper the performance of Model Predictive Control (MPC) and PID based strategies to optimally recover waste heat using Organic Rankine Cycle (ORC) technology is investigated. First relationship between evaporating temperature output power experimentally evaluated, concluding that for some given source conditions there exists an optimal which maximizes energy production. Three different control MPC are developed in order not only maximize production but ensure safety machine. For case...
Development of a first principles model system is not only time- and cost-consuming task, but often leads to structures which are directly usable design controller using current available methodologies. In this paper we use sparse identification procedure obtain nonlinear polynomial model. Since NP-hard problem, relaxed algorithm employed accelerate its convergence speed. The obtained further used inside the Extended Prediction Self-Adaptive control (NEPSAC) approach Nonlinear Model...
A concentrated solar power (CSP) biomass combined heat and (CHP) system based on organic Rankine cycle (ORC) technology developed in the framework of EU founded BRICKER project is presented.The CHP coupled with recovery ventilation novel insulation material has aim reducing energy consumption existing building by up to 50%.A simplified approach implement a dynamic model proposed.The firstly used investigate performances control logic under extreme working condition.Secondly, effectiveness...