Maria E. Mondejar

Maria E. Mondejar
Technical University of Denmark | DTU · Department of Mechanical Engineering

Ph.D.

About

41
Publications
13,378
Reads
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919
Citations
Additional affiliations
May 2018 - October 2019
Technical University of Denmark
Position
  • Researcher
June 2013 - August 2015
Lund University
Position
  • PostDoc Position
June 2012 - November 2012
National Institute of Standards and Technology, Boulder, United States
Position
  • Guest researcher

Publications

Publications (41)
Conference Paper
Packed-bed rock thermal energy storage with solids for heat storage is a cost-effective solution. Approaches to model thermal storage systems range from simplified models based on analytical solutions to the partial differential equations representing the system, to more advanced models based on the finite volume method, or even complex models base...
Article
The installation of an organic Rankine cycle unit on the exhaust line of a marine engine imposes an increase in the backpressure on the engine, resulting in a decrease of the engine performance and a variation of the available waste heat. In this paper, a method is presented for the optimal design of organic Rankine cycle power systems for waste he...
Article
The pollutant emissions from ships in harbor are a pressing concern due to their direct impact on the health of the population. The use of electric-battery propulsion is a viable solution to reduce the emissions in coastal areas, but it is only applicable to small ferries. Large cruise ships commonly utilize shore power connection to provide onboar...
Article
Liquefied natural gas is stored on board vessels under cryogenic conditions, and hence, fuel preheating is required before injection in the engine. The cooling effect associated with this preheating phase can be utilized to decrease the vessel’s overall fuel consumption. Previous works focused on evaluating the prospects for cold energy recovery fo...
Article
The phase-out of hydrofluorocarbons triggered by the enforcement of new environmental regulations forces the search for new substances that comply with the stricter environmental requirements, while offering similar thermodynamic performance and safety features. Olefins containing fluorine and/or chlorine have the potential to be used as replacemen...
Article
Full-text available
When considering waste heat recovery systems for marine applications, which are estimated to be suitable to reduce the carbon dioxide emissions up to 20%, the use of organic Rankine cycle power systems has been proven to lead to higher savings compared to the traditional steam Rankine cycle. However, current methods to estimate the techno-economic...
Article
Density measurements from single-sinker magnetic suspension densimeters need to be corrected to compensate for the magnetic effects of the measuring cell materials and the fluid on the coupling transmission system. While the magnetic effect of the densimeter materials can be easily determined, the fluid effect requires the calculation of an apparat...
Article
Full-text available
This work evaluates the performance of the group contribution volume translated Peng–Robinson model when predicting the vapor–liquid equilibrium and single phase densities of 28 refrigerant mixtures with low global warming potential and zero ozone depletion potential. Cubic equations of state, and particularly the Peng–Robinson equation of state, a...
Article
A general heat transfer correlation to predict the thermal performance of zeotropic mixture flow boiling is essential for an optimal evaporator design in thermodynamic cycles using zeotropic mixtures as working fluids. This work aims at developing a new general correlation to predict the flow boiling heat transfer of zeotropic mixtures in horizonta...
Article
The International Maritime Organization recently revised the regulations concerning nitrogen and sulphur oxides emissions from commercial ships. In this context, it is important to investigate how emission abatement technologies capable of meeting the updated regulation on nitrogen oxides emissions affect the performance of waste heat recovery unit...
Article
Plate heat exchangers have been widely applied in numerous industrial applications since their first commercial exploitation in the 1920s. Enhancing the thermal-hydraulic performance of plate heat exchangers is of crucial importance for the energy conversion as well as for the improvement of the system economy, through savings in the capital invest...
Article
Full-text available
This study demonstrates a method for predicting the dynamic fuel consumption on board ships using automated machine learning algorithms, fed only with data for larger time intervals from 12 hours up to 96 hours. The machine learning algorithm trained on dynamic data from shorter time intervals of the engine features together with longer time interv...
Article
Halogenated olefins can be an attractive alternative to working fluids that are under consideration for phase-out. In order to evaluate the potential of halogenated olefins as working fluids for organic Rankine cycle units with a realistic perspective it is necessary to predict both their primary thermophysical properties and their associated uncer...
Conference Paper
Full-text available
This study demonstrates a method for predicting the dynamic fuel consumption on board ships using automated machine learning algorithms, fed only with data for larger time intervals from 12 hours up to 96 hours. The machine learning algorithm trained on dynamic data from shorter time intervals of the engine features together with longer time interv...
Conference Paper
Full-text available
The increasing awareness about the environmental impact of shipping and the increasingly stricter regulations introduced by the International Maritime Organization are driving the development of solutions to reduce the pollutant emissions from ships. While some previous studies focused on the implementation of a specific technology, others consider...
Article
Diesel engines are by far the most common means of propulsion aboard ships. It is estimated that around half of their fuel energy consumption is dissipated as low-grade heat. The organic Rankine cycle technology is a well-established solution for the energy conversion of thermal power from biomass combustion, geothermal reservoirs, and waste heat f...
Article
The search of novel working fluids for organic Rankine cycle power systems is driven by the recent regulations imposing additional phase-out schedules for substances with adverse environmental characteristics. Recently, nanofluids (i.e. colloidal suspensions of nanoparticles in fluids) have been suggested as potential working fluids for organic Ran...
Chapter
Although geothermal energy has been widely deployed for direct use in locations with especial geologic manifestations, its potential for power generation has been traditionally underestimated. Recent technology developments in drilling techniques and power conversion technologies from low-temperature heat resources are bringing geothermal energy to...
Article
The selection of appropriate working media for organic Rankine cycles (ORC) is essential for the optimization of their performance. Dry fluids are widely used in existing ORC because, unlike wet fluids, they do not need to be superheated to avoid wet expansion that may cause damage to the expander. However, regeneration is sometimes needed for flui...
Article
Full-text available
The increasingly restrictive regulations for substances with high ozone depletion and global warming potentials are driving the search for new sustainable fluids with low environmental impact. Recent research works have pointed out the great potential of fluorine- and chlorine-based olefins as refrigerants and solvents, due to their environmentally...
Article
In this work we present the quasi-steady state simulation of a regenerative organic Rankine cycle (ORC) integrated in a passenger vessel, over a standard round trip. The study case is the M/S Birka Stockholm cruise ship, which covers a daily route between Stockholm (Sweden) and Mariehamn (Finland). Experimental data of the exhaust gas temperatures,...
Article
In this study, the average values of the engines exhaust temperatures and mass flow rates, for each load case, were used as inputs for a model of an ORC. The main parameters of the ORC, including working fluid and turbine configuration, were optimized based on the criteria of maximum net power output and compactness of the installation components....
Article
We present experimental measurements of the density, speed of sound, and vapor pressure of trans-1-chloro-3,3,3-trifluoropropene, which is also known as R1233zd(E). Densities were measured over the temperature range from (215 to 444) K, with pressures from (0.3 to 24.1) MPa. Sound speed data were measured at temperatures between (290 and 420) K, wi...
Article
The composition of biogas may vary significantly due to the diversity of production sources, making it essential to have a detailed knowledge of their thermophysical properties in order to develop and validate methods for the estimation of density, heat capacity and calorific value of biogas and biomethane. In this work the thermodynamic behavior o...
Conference Paper
Full-text available
Waste heat recovery systems for power generation are gaining interest among the marine transport sector as a solution to accomplish the upcoming more restrictive regulations on emissions, and to reduce the total fuel consumption. In this paper we evaluate how a waste heat recovery system based on a regenerative organic Rankine cycle (rORC) could im...
Chapter
In this chapter a thorough review of the latest research findings on power generation from non-conventional low heat sources is presented. Main discoveries and results of research works ranging from source exploitation technologies to final power production are reported and discussed to offer an overview of their potential. Firstly the concept of l...
Article
Full-text available
New technology requirements derived from the exploitation of novel energy resources, and the needs for improvement of the energy efficiency of current power generation systems are pushing the industry towards the search of alternative working fluids. The great challenge for these non-conventional fluids is to provide satisfactory performances and f...
Conference Paper
Due to the increasing interest of producing power from renewable and non-conventional resources, organic Rankine cycles are finding their place in today’s thermal energy mix. The main influencers on the efficiency of an organic Rankine cycle are the working fluid and the expander. Therefore most of the research done up to date turns around the sele...
Article
An estimation of the Enhanced Geothermal System's theoretical technical potential for the Iberian Peninsula is presented in this work. As a first step, the temperature at different depths (from 3500 m to 9500 m, in 1000 m steps) has been estimated from existing heat flow, temperature at 1000 m and temperature at 2000 m depth data. From the obtained...
Article
Full-text available
Increasing efforts to produce power from renewable resources and improve the efficiency of current industrial processes have turned the spotlight on organic Rankine cycles (ORC). The use of refrigerant mixtures in these cycles offers a wide range of possibilities for fluid selection and optimization. Moreover, zeotropic mixtures are reported to yie...
Article
In the last few years, coal mine methane (CMM) has gained significance as a potential non-conventional gas fuel. The progressive depletion of common fossil fuels reserves and, on the other hand, the positive estimates of CMM resources as a by-product of mining promote this fuel gas as a promising alternative fuel. The increasing importance of its e...
Article
In this work an estimation and comparison of the technical and sustainable potentials of EGS (Enhanced Geothermal Systems) in Europe is presented. The temperatures at depths of (3500–9500) m were firstly calculated from the available data of temperatures at surface, 1000 m and 2000 m depth, and heat flow. Next the available thermal energy stored in...
Article
Experimental characterization of the thermodynamic behavior of gas binary mixtures containing components of fuel gases is of great importance due to the proved lack of reliable data of thermodynamic properties of mixtures. These data are essential not only for the improvement and test of the current reference equation of state for natural gases and...
Article
The current world status of geothermal electricity production, including installed capacities, number of units and energy produced by exploitation technology, is presented in this paper. Four geothermal model plants based on different modes of high enthalpy technologies are analyzed from energy, environmental and economic points of view for specifi...
Article
Recently our group published a set of (p, ρ, T) data for two (carbon dioxide + nitrogen) mixtures with a low carbon dioxide content (xCO2=0.10,0.15)(xCO2=0.10,0.15). These data showed larger relative deviations from the GERG-2008 equation of state than expected, specially at low temperatures, high pressures, and for the mixture with higher carbon d...
Thesis
Full-text available
This thesis deals with the thermodynamic characterization of gaseous binary mixtures related with alternative fuels through accurate density measurements carried out with a single sinker densimeter with magnetic suspension coupling. Several setup modifications affecting each of the measured magnitudes were performed to reduce the main uncertainty s...
Article
Comprehensive (p, ρ, T) measurements on two binary mixtures (0.10 CO2+0.90 N2 and 0.15CO2+0.85 N2) were carried out in the gas phase at seven isotherms between (250 and 400)K and pressures up to 20MPa using a single sinker densimeter with magnetic suspension coupling. A total of 69 (p, ρ, T) data for the first mixture and 69 (p, ρ, T) data for the...
Article
The single sinker densimeter with magnetic suspension coupling is one of the state of the art methods for the accurate measurement of fluid densities. The uncertainties of experimental pressure, density and temperature data, measured with a single sinker densimeter, were thoroughly evaluated following the uncertainty propagation law. The main uncer...
Article
The development of the current reference equation of state for natural gas and other related mixtures (GERG 2008) was based on a wide up-to-date database of experimental thermodynamic properties. This extensive data bank showed, however, a significant lack of data for many of the possible binary mixtures of natural gas components. In fact, density...
Article
From an industrial point of view, polymeric foams are of great importance because of their good mechanical and thermal properties and their low weight. Among them, polyurethane foams are the most versatile and, thus, the most consumed. Traditional methods for polyurethane foaming have the disadvantages of negative spin-offs due to chemical foaming...

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Projects

Projects (2)
Archived project
Study the integration of an Organic Rankine Cycle for waste heat recovery with a wet scrubber for SOx- and a EGR for NOx-reduction.