P.J.W. van den Engel
Please Note
12 records found
1
Satisfying thermal comfort in indoor spaces is still a challenge in terms of energy saving, and several HVAC (Heating, Ventilation, and Air-Conditioning) systems have been proposed for this purpose. This paper conducts an analysis to evaluate and optimize the long-term operation of a novel HVAC system installed at The Green Village, a living lab in Delft, the Netherlands. This system comprises all-glass facades with steerable solar shades, sky windows, a climate tower equipped with Phase-Change Material (PCM), a heat recovery unit, and a heat pump. The current analysis draws on transient modeling to predict the system's behavior while relying on constrained nonlinear optimization to select the optimal design parameters (e.g. floor heat capacity and solar absorptance) and optimal operational conditions (e.g. use of PCM and heat recovery unit, aperture of sky windows and solar shadings). The goal is to schedule the control inputs to operate the system as much as possible as a passive energy system, with minimal active power all year round. The results show that the optimization can reduce the yearly heat demand by around 10.6%, with the solar shadings being the most significant component to be optimized. Furthermore, the optimized system is capable to supply 58% of the annual thermal demand passively – In this case, an auxiliary thermal demand of only 27 kWh/m2/year is required, which may qualify the system as a low-energy building.
This research evaluates the performance of a Phase Change Material (PCM) battery integrated into the climate system of a new transparent meeting center. The main research questions are: a. “Can the performance of the battery be calculated?” and b. “Can the battery reduce the heating and cooling energy demand in a significant way?” The first question is answered in this document. In order to be able to answer the second question, especially the way the heat loading in winter should be improved, then more research is necessary. In addition to the thermal battery, which consists of Phase Change Material plates, the climate system has a cross-flow heat exchanger and a heat pump. The battery should play a central role in closing the thermal balance of the lightweight building, which can be loaded with hot return or cold outdoor air. The temperature of the battery plates is monitored by multi-sensors and simulated by the use of PHOENICS (Computational Fluid Dynamics) and MATLAB. This paper reports reasonable agreement between the numerical predictions and the measurements, with a maximum variance of 10%. The current coefficient of performance for heating and cooling is already high, more than 27. There is scope for increasing this much further by making use of the very low-pressure difference of the battery (below 25 Pascal), low pressure fans and the ventilation system as a whole.
Innovative passive solutions: Designing for 2050
Report Workshop CLIMA 2022
A reception desk is the main workplace in a hospital hall. A reception desk can be closed, i.e. physically separates the personnel from the environment of the hall. A reception desk can also be open, thus without a physical separation between personnel and patients and visitors. In a hospital, in general, an open reception desk is favoured for a more welcoming atmosphere for patients and visitors. This more open reception desk, however, often causes the personnel to
experience low temperatures and draught.
From this study it is clear that it is very difficult design a thermally comfortable reception desk in a hospital. The quest for a reception that expresses openness and transparency clearly hinders the design for a comfortable reception desk. On the other hand, the small number of people at the reception desk is in no comparison to the hundreds of staff and patients for which the hospital is also designed.
Many solutions to improve thermal comfort at a reception desk are already known. The exact cause of the experienced draught and the best solutions, however, are difficult to determine. Scale models or CFD simulations should be used as a guide for design a reception desk in a hospital or when solving thermal comfort problems.
A new cause of draught, people moving past the reception desk, was identified and quantified. As a result, a completely open reception desk inside a large atrium with a lot of people moving past might not be possible without either closing off the reception desk, or increasing the temperature at the reception desk. ...
A reception desk is the main workplace in a hospital hall. A reception desk can be closed, i.e. physically separates the personnel from the environment of the hall. A reception desk can also be open, thus without a physical separation between personnel and patients and visitors. In a hospital, in general, an open reception desk is favoured for a more welcoming atmosphere for patients and visitors. This more open reception desk, however, often causes the personnel to
experience low temperatures and draught.
From this study it is clear that it is very difficult design a thermally comfortable reception desk in a hospital. The quest for a reception that expresses openness and transparency clearly hinders the design for a comfortable reception desk. On the other hand, the small number of people at the reception desk is in no comparison to the hundreds of staff and patients for which the hospital is also designed.
Many solutions to improve thermal comfort at a reception desk are already known. The exact cause of the experienced draught and the best solutions, however, are difficult to determine. Scale models or CFD simulations should be used as a guide for design a reception desk in a hospital or when solving thermal comfort problems.
A new cause of draught, people moving past the reception desk, was identified and quantified. As a result, a completely open reception desk inside a large atrium with a lot of people moving past might not be possible without either closing off the reception desk, or increasing the temperature at the reception desk.
Hybrid ventilation
A design guide