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Chapter 10 of the book "Energy Conservation Guidebook" is presented. It explores pressure measurement in building equipment. Topics discussed include applications of pressure measurement including air-conditioning equipment and airflow, description of pressure gauges and types of manometers for different pressure-measuring applications.

The article offers information on the soundproofing and reducing airflow to improve the sound-blocking qualities of walls and ceilings. Topics include need of Stopping airflow through walls, ceilings, floors, windows and doors for soundproofing; adding soundproofing board and insulation to reduce noises; and reducing noise by decorating with soft materials that absorb sound such as rugs, fabric wall hangings and soft furniture. Also offers instruction for installing resilient steel channels.

This paper deals with the utilisation of the von Karman vortex street principle to maximise air flow into buildings. Von Karman Vortex Street is a succession of eddies created close to the building that break away alternatively from both sides. A case study of 2 rectangular buildings placed at a certain distance from each other is presented and the effect on ventilation is determined. The stagnation region appears in the closest region downstream of the bluff body (building) and is a factor which considerably influences vortex shedding and subsequently ventilation. The stagnation region has to be minimized for maximizing the air flow. Vortex streets can result in natural ventilation which can save energy due to reduced running of electrical appliances. Thus, the green building concept can be satisfied. Based on this study, doors and windows can be placed at the wake regions, resulting in maximum ventilation. [ABSTRACT FROM AUTHOR]

Chapter 13 of the book "2009 ASHRAE Handbook: Fundamentals" is presented. The chapter offers information on two indoor environmental modeling methods used in calculating airflows and contaminant concentrations in buildings which are computational fluid dynamics and multizone network airflow modeling. Topics for each method covered mathematical background, practical modeling advice, model validation, and application examples.

The article presents a detailed analysis of venting and positive pressurisation systems. It discusses the use of passive venting, a technology that has been demonstrated to be effective in practice, both by computer modeling and by measuring the gas concentrations and flow rates in constructed systems. It emphasizes the importance of long-term monitoring of gas concentrations and air flow rates.

Chapter 22 of the book "2008 ASHRAE® Handbook: Heating, Ventilating and Air-Conditioning Systems and Equipment," is presented. It discusses the fundamentals of air cooling and dehumidifying coils, including its uses, coil construction and arrangement and appropriate coil selection. The chapter explains the principle of airflow resistance and heat transfer and performances of sensible and dehumidifying cooling coils. A discussion on the methods of determining refrigeration load is also presented.

Chapter 25 of the book "2008 ASHRAE® Handbook: Heating, Ventilating and Air-Conditioning Systems and Equipment" is presented. It describes various technologies for air-to-air energy recovery including discussion on airflow arrangements and some of its technical and design considerations. The chapter also compares different air-to-air recovery systems and presents issues on thermal and economic performance, maintenance and other operational related matters, with emphasis on energy recovery for ventilation.

Boundary layer solutions around body of revolution are analyzed throughout this study. Sphere, ellipsoids that have different fineness ratios and bodies which are obtained by the Karman-Trefftz airfoils that are revolved around their axis are used as axially symmetrical bodies. The velocity distributions that are needed in order to solve boundary layer equations are obtained by the solutions of potential flow. Therefore, an analytic solution of potential flow around ellipsoid and axial singularity distribution method are used. Thwaites-Walz method, which gives approximate solutions for all geometries, is applied to solve boundary layer equations. In order for the solutions to be tested, an analytic solution that gives an exact solution for sphere which is a special condition of ellipsoid is utilized. In order to obtain solutions in a quick way, a software program is developed in Visual Basic. [ABSTRACT FROM AUTHOR]

Chapter 16 of the book "2005 ASHRAE Handbook—Fundamentals" is presented. It discusses the impact of airflow around buildings to the safety of the workers, process and building equipment operation, and weather and pollution protection at inlets. It explores basic information in evaluating windflow patterns, estimating wind pressures, and identifying problems caused by the effects of wind on intakes and exhaust.

The article presents information on high efficiency air filtration for cleanrooms. The supply of air to a cleanroom must be filtered to ensure the removal of particles that would contaminate the process being carried out in that room. In cleanrooms, high efficiency filters are used for the dual purpose of removing small particles and, in unidirectional flow cleanrooms, straightening the airflow. High efficiency filters are usually constructed in two ways, i.e. deep pleated or mini-pleated. Both methods are used to ensure that a large surface area of filter paper is compactly and safely assembled into a frame so that there is no leakage of unfiltered air through it.

The article presents information on cost-efficiency and energy saving concepts for cleanrooms. The cost of systems employing unidirectional flow is intrinsically high. Moreover the cost of all air circulation systems-cleanroom systems and others-is directly proportional to the air flow rate. Creative design engineering in cleanroom technology is thus consciously directed towards minimizing the air flow rate, by various methods. One can do this by reducing the room areas where unidirectional air flow is maintained to the minimum required by the process technology. Another way is to employ alternative design concepts which effectively separate the process from contamination and people.

A chapter from section 6 of the book "Sailpower: Trim and Techniques for Cruising Sailors" is presented. The chapter explains the role of telltales in headsails. Telltales serve as determinants of the condition of airflow across the sail and a guide to correct sheet lead position on a reach. Sailing and practise are emphasized as integral to determining the optimum trim for a sail boat.

The article discusses the use of positive pressurisation below buildings in Great Britain to prevent gas ingress. It offers information on positive pressurisation which pumps air into the void or void former below a floor slab to create a pressure zone that is more than gas pressure in the ground. It also explores ongoing maintenance requirement for active systems and the issues with their energy efficiency.

Chapter 18 of the book "50 Ways to Improve Your Weather Forecasting" is presented. It presents guidelines on how to fine-tune a weather forecast in case of a broken airflow. The regular flow of air generated by the wind will be broken if the airflow encountered something in its path. In case of a broken airflow, there would be variation in wind strengths and directions in a localized area.

The article discusses the use of active venting below buildings in Great Britain to prevent gas ingress. Active venting reportedly uses fans to improve the airflow in underfloor voids and requires a gas monitoring system to activate the fans in case gas levels exceeded the set values. Also examined is the misconception are more reliable if they are not turned off.

A definition of the term "Cubic Feet per Minute" (CFM) is presented. It refers to a measurement of the velocity at which air flows into or our of a space. CFM is used in reference to a computer cooling system and to an air-cooling system that is supporting overclocking.