The laminar flow for a backwards facing step is studied. This work was initially part of the work presented in [l]. In that work low-Reynolds number effects was studied, and the plan was also to include laminar flow. However, it turned out that when the numerical predictions of the laminar flow (Re= 118) was compared to the experiments of Restivo [2), we found a large discrepancy. We believe that there is something wrong in that experimental investigation.

The principal soil gases of current concern to building are radon and landfill gas. The flow of these is generally thought to be dominated by viscous flow driven by pressure differences. This paper compares analytical results presented in two previous papers, an experiment to measure the flow of gas in soil and an analytical result found by another technique. The results support the findings of the previous work.

The principal soil gases of current concern to building are radon and landfill gas. The flow of these is generally considered to be dominated by viscous flow driven by pressure differences. This paper presents results for the pressure-driven flow of gas for problems relating to a building with a bare soil floor, for example below a suspended timber floor. This paper builds on a previous paper by mapping the solution to a mixed boundary problem onto another geometry. In a third paper these results will be compared with an analytical result from elsewhere and an experiment.

The principal soil gases of current concern to building are radon and landfill gas. The flow of these is generally thought to be dominated by viscous flow under a pressure gradient. This paper presents results for such pressure-driven flow of gas for problems relating to a building with a bare soil floor, for example below a suspended timber floor. The solutions address this problem in two dimensions as a mixed boundary problem.

Isolation rooms for Tuberculosis in fifteen hospitals have been surveyed and measured in twophases. In phase 1 the isolation rooms in seven hospitals were checked ater the hospitalsrenovation construction had been finished. However in phase 2 all the design drawings of theair-conditioning and ventilation/exhaust system of isolation rooms in eight other hospitalswere checked and revised by ERLs engineer before starting construction. The survey itemsinclude ventilation rate ' static pressure ' temperature and humidity.

This present work has theoretically investigated coupled heat and mass exchangemechanisms in counterflow rotary dehumidifier with the mixed desiccant of LiCl and additives,used in air conditioning systems. Mathematical model has been derived, based on one-dimensionaltransfer model and Polyni potential theory (theory of water chemical potential)and solved, using digital computer. The profiles of temperature and absolute humidity distributionin the matrix have been obtained. Analysis shows, that the direction of mass transfer isopposite to positive water vapour partial pressure.