Study of variants to classical mechanical exhaust ventilation systems by using mechanical exhaust in habitable rooms

Nowadays, due to the higher energy performance of dwellings, ventilation plays an increasing role in maintaining a good indoor comfort. Therefore new ventilation strategies in combination with demand controlled ventilation are needed to accomplish high energy-efficient ventilation (limiting ventilation losses and auxiliary energy consumption) while providing good indoor air quality, thermal and acoustic comfort.

Effectiveness of Ventilative Cooling Strategies in Hot and Dry and Temperate Climates of India

Increasing use of air-conditioning in India is applying upward pressure on energy demand and may have implications on dependability. Electrical energy can be saved if favourable outdoor conditions are effectively utilized for cooling buildings with the minimum use of energy. This could be specifically applicable to residences where night-time use is more predominant for cooling by air conditioning systems but also aligns favourably with suitable outdoor conditions to be used as ventilative cooling.

Recommendable supply air rates for residential housing – A simulation study considering CO2 concentration, relative humidity, TVOC emissions and mould risk

In an extensive simulation study using a multi-zone airflow and contaminant transport calculation software (CONTAM) recommendations for the supply air rates for residential housing were derived as input for the revision of the Austrian standard ÖNORM H 6038 (2014). The floor plan, the occupancy and the contaminant and humidity sources are modelled to represent a typical Austrian housing situation. A humidity buffering model is also implemented. Based on common thresholds for CO2, relative humidity (r.h.) and TVOC the so-called relative threshold deviation is determined.

Numerical evaluation of the airtightness impact on airflow pattern in mechanically ventilated dwellings in France

The objective of this paper is to assess the impact of the envelope airtightness on airflow patterns for single detached dwellings depending on the ventilation system.

Simulation analysis for indoor temperature increase and reduction of heating load in the detached house with buoyancy ventilated wall in winter

Detached residential wooden houses are a common type of housing in Japan. Decay of wooden components within the walls is easily caused by condensation or defective flushing. To solve this problem, a double-skin system with a room-side air gap was developed. In this system, during winter, the airflow in the ventilated wall circulates freely around the whole house. Therefore, during daytime, the airflow moves solar heat to base, and releases heat to the house at night which can increase indoor temperature.

Numerical simulation of indoor air quality - mechanical ventilation system supplied periodically vs. natural ventilation

Building integrated renewable energy sources e.g. photovoltaic system is one of the promised solution for improving energy efficiency in building. However such kind of the system is restrained by irregular power supplied and necessity to convert current from direct to altering form. Therefore, very often the electrical energy generated by photovoltaic system cannot be effectively utilised to supply building devices, e.g. components of HVAC or lighting system.

System for controlling variable amount of air ensuring appropriate indoor air quality in low-energy and passive buildings

In low energy buildings and passive houses due to very low heating demands integrated heating and ventilation (VAV or DCV) systems are used to provide proper indoor climate conditions – thermal comfort and indoor air quality. Dynamic changes of indoor conditions result in permanent changes in air flow.

Simulation of night ventilation performance as a support for an integrated design of buildings

Passive cooling by night ventilation is one of the most promising approaches to reduce cooling energy demand of office buildings in moderate climates. However, the effectiveness of this system depends on many parameters.

Presenting LOBSTER, an innovative climate chamber, and the analysis of the effect of a ceiling fan on the thermal sensation and performance under summer conditions in an office-like setting

Thermal comfort studies have been performed so far either in closed climate chambers with controlled conditions or non-controlled conditions during field studies. Detailed analyses of mechanisms behind the adaptive comfort models are therefore hardly possible. This paper presents a newly constructed climate chamber in Karlsruhe (Germany) along with the complete chain from subjective experiments, via data analyses, model development and implementation into dynamic building energy simulation until the formation of a decision base for or against a renovation measure for a confined case.

Estimation of annual energy loss by indoor air mixing

Excess energy consumption of HVAC system is not usually noticed without the dissatisfaction to thermal environment. Recently it has become easier to discover it in buildings with the aid of Building Energy Management System (BEMS). Indoor Air Mixing loss occurs in an office when the perimeter zone is heated by one HVAC system and the interior zone is cooled by the other system. The aim of this study is the quantitative analysis of the mixing energy loss in office buildings. Experiments are conducted in a full-size experiment room.

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