Case Study on Ventilation for Improving the Hygrothermal Behaviour of Emergency Temporary Housing under Japanese Conditions

Emergency Temporary Housing units consisting of a light-gauge steel brace construction were built following the Great East Japan Earthquake of March 11, 2011 (see Appendix). About 30,000 of these units are still in service following a delay in rehabilitation and reconstruction. The heat bridge portion in this kind of construction causes surface condensation in rooms. In addition, condensation damage on the steel roof surface in the attic space is also relatively large.

Simulated Influence of Indoor Climate and Ventilation on Schoolwork Performance in Estonian Manor Schools

Indoor temperature and humidity conditions as well as CO2 and airborne mould concentrations were measured in four manor schools in the Estonian cold climate. Based on these measurements, the influence of the indoor climate on the performance of schoolwork was assessed. The indoor environmental quality in manor schools turned out to be quite poor due to the inadequate performance of ventilation and heating systems. Intermittent stove heating was found to secure the minimum temperature in general but in winter thermal comfort was not always guaranteed.

Prospects of Improving the Indoor Air Quality in Classrooms by Reactivating Historic Ventilation Stacks

Stack ventilation systems were installed in German schools constructed around 1900 and are no longer in operation. The aim of this study was to show how reactivating these systems could improve the indoor air quality in classrooms. Ventilation stacks were reactivated in three classrooms in a school while a fourth classroom, which was naturally ventilated via openable windows, served as the reference case. All classrooms were measured for carbon dioxide levels, air temperature and relative humidity.

Experimental and Modelling Investigations of Air Exchange and Infection Transfer due to Hinged-Door Motion in Office and Hospital Settings

Occupants spend a significant amount of time indoors where temperature and air quality has an important impact on their comfort, health and work performance. Understanding the role of airflow exchange between spaces is crucial to describe the processes of mixing and transport of substances driven by air motion and therefore essential for evaluating indoor air quality. This work presents the results of field measurements and laboratory experiments designed to characterise door operation and to quantify its influence on air volumes exchanged between rooms due to door motion.

Airflow Patterns through Single Hinged and Sliding Doors in Hospital Isolation Rooms

Door operation and the subsequent passage of occupants through the doorway can cause containment failures in hospital isolation rooms. Typically hinged doors are used between the isolation room and anteroom/corridor in healthcare facilities. However, sliding doors can reduce door induced airflows through the doorway and hence effectively reduce the contaminant outflow during the door operation.

Guest Editorial - Ventilation for Healthy Indoor Environments in Various Types of Buildings - Extended Papers from Indoor Air 2014

Exposure to air pollution from both outdoor and indoor origins can cause a myriad adverse health effects including cardiovascular and respiratory diseases, lung cancer and mortality. Approximately 3.7 million people worldwide died prematurely due to outdoor air pollution in 2012. As people spend more than 90% of their time indoors, the majority of exposure to outdoor air pollution actually occurs indoors, let alone the persistence of various indoor pollution sources indoors.

Thermal Sensation of Thai Students in an Air Conditioned Space with a Pond Type Water Source and Air Velocity Step Change

This paper investigates thermal sensation in an air conditioned space with and without a water source such as a water pond and small fountain in Thailand. Questionnaires were collected from experiments involving 140 subjects divided into groups of 6-14 people sitting in controlled rooms of sequences of air velocity with and without a water source. Furthermore, another 41 subjects participated in a room with a large picture of a waterfall and were later exposed to a water source.

Semi-Empirical Models for Buoyancy-Driven Ventilation - A Literature Study

A literature study is presented on the theories and models dealing with buoyancy-driven ventilation in rooms. The models are categorised into four types according to how the physical process is conceived: column model, fan model, neutral plane model and pressure model. These models are analysed and compared with a reference model. Discrepancies and differences are shown, and the deviations are discussed. It is concluded that a reliable buoyancy model based solely on the fundamental flow equations is desirable.

Assessment of the Fluid Dynamics Aspects of a Vehicle Ventilation System

Vehicular air conditioning systems are directly affected by the ducts and fans of the ventilation system. This paper presents an experimental study of the influence of the geometry of the air ducts and fans on the performance of an automotive air conditioning system. The flow rate, pressure drops and power requirement demand were evaluated for different geometrical and operational conditions. A test bench was used that constituted the air-box of an automotive air conditioning system, composed of the air ducts, the centrifugal blower, and an instrumental panel.

Experimental and Numerical Testing of an Induction Variable Air Volume (VAV) Controller with Two Damper Blades

A VAV (Variable Air Volume) air conditioning system without reheat of the air supplied is generally regarded as energy efficient. Re-heat can be avoided when induction VAV controllers are used instead of conventional controllers since primary airflow can be reduced to about 10−20% of its nominal value without a draught risk.

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