CASPA-ADM: a mission concept for observing thermospheric mass density

Cold Atom technology has undergone rapid development in recent years and has been demonstrated in space in the form of cold atom scientific experiments and technology demonstrators, but has so far not been used as the fundamental sensor technology in a science mission. The European Space Agency therefore funded a 7-month project to define the...

Gas-surface interactions modelling influence on satellite aerodynamics and thermosphere mass density

The satellite acceleration data from the CHAMP, GRACE, GOCE, and Swarm missions provide detailed information on the thermosphere density over the last two decades. Recent work on reducing errors in modelling the spacecraft geometry has greatly reduced scale differences between the thermosphere data sets from these missions. However, residual...

Seasonal Hydrogen Storage in Dutch Depleted Gas Reservoirs: A Feasibility Study for The Netherlands

The Netherlands will need to transform her traditionally fossil fueled energy system in the coming decades to achieve the goal of reducing CO2 emissions to net-zero in 2050. Therefore, an increase in renewable energy sources as solar and wind energy in the overall energy mix will be essential. However, due to the highly variable energy...

A comparison of steam reforming concepts in solid oxide fuel cell systems

Various concepts have been proposed to use hydrocarbon fuels in solid oxide fuel cell (SOFC) systems. A combination of either allothermal or adiabatic pre-reforming and water recirculation (WR) or anode off-gas recirculation (AOGR) is commonly used to convert the fuel into a hydrogen rich mixture before it is electrochemically oxidised in the...

Exploring the response of a resistive soot sensor to AC electric excitation

The resistive particulate matter sensor is a simple device that transduces the presence of soot through impedance change across inter-digital electrodes (IDEs). We investigate the information provided by impedance spectroscopy over the frequency range from 100 Hz to 10 kHz for two purposes. The first is to investigate the opportunities for an...

Hydrogen-natural gas combustion in a marine lean-burn SI engine: A comparitive analysis of Seiliger and double Wiebe function-based zero–dimensional modelling

With increasingly stringent emission regulations, marine natural gas engines need to improve their performance. Various proven advantages of hydrogen-natural gas (H-NG) blends make them a promising enhanced fuel solution. Although modelling of H-NG combustion has been investigated before, mostly using CFD models, the literature on the...

Impedance Spectroscopy for Enhanced Data Collection of Conductometric Soot Sensors

Impedance spectroscopy in the frequency range 100 Hz to 10 kHz has been applied to the Inter-Digitated Electrode (IDE) structure that is conventionally operated as a resistive sensor for the measurement of Particulate Matter (PM). The measurement of both the in-phase (resistive) and out-of-phase (capacitive) components of the impedance over this...

Generic Analysis Methods for Gas Turbine Engine Performance: The development of the gas turbine simulation program GSP

Numerical modelling and simulation have played a critical role in the research and development towards today’s powerful and efficient gas turbine engines for both aviation and power generation. The simultaneous progress in modelling methods, numerical methods, software development tools and methods, and computer platform technology has provided...

Depressurizing green gas: Analizing the status quo of green gas injection and finding possible facilitating roles for Alliander

There is an increased interest in green gas injection, when looking at both governmental policies and requests for green gas injection made to Dutch gas distribution system operator Liander. Alliander, as a holding, owns network operator Liander. Alliander strives for a more social role in helping society achieve its (sustainable) goals, and...