Outdoor Environment

The steady pressurisation method measures the building leakage in a range of high pressures, typically 10-60 Pa. It is implemented by creating a steady pressure difference across the building envelope and measuring the corresponding airflow exchange rate between the indoor and outdoor simultaneously. This method has been widely used and accepted as the standard test for demonstrating building air-tightness compliance. Conversely, the novel pulse technique, has been developed to measure the building air leakage at low pressures typically in the range of 1-10 Pa.

This paper introduces an experimental study of enclosure airtightness testing of an outdoor chamber using both the pulse technique and the blower door method.  This investigation is a 2nd stage comparison study following the previous testing of a house-sized chamber in a sheltered environment.  The outdoor chamber in this study has dimensions, approximately half that of a standard 20ft long shipping container.  Multiple openings were installed into the chamber’s envelope to provide a leakage level and characteristics similar to an average UK house.

The Universal Thermal Climate Index UTCI assesses the interaction of ambient temperature, wind, humidity and radiant fluxes on human physiology in outdoor environments on an equivalent temperature scale. It is based on the UTCI-Fiala model of human thermoregulation and thus also allows for thermal comfort prediction.

It is difficult to model those complicated objects around buildings, which will obviously affect the flow patterns and temperatures of the outdoor environment. In this paper new method is concluded to solve this kind of modeling problems. Those centralized objects are treated as porous media which will also affect the air flow and turbulence. New source terms are coded into the model to simulate the characteristics. In this way, we can easily model as many as influential factors into the simulation and save much computational time and get a satisfactory result.