Supply ventilation

Shepelev I. A. 1961. Supply ventilation jets and air fountains. In Proceedings of the Academy of Construction and Architecture of the USSR, no. 4. 

Fresh air supply ventilation systems (heat recovery or nonheat recovery). 

All hydrocarbon fire mechanisms and estimates will be affected by to some extent of flame stability features such as varying fuel composition as lighter constituents are consumed, available ambient oxygen supplies, ventilation patterns, and wind effects. Studies into these effects have generally not progressed to the level where precise estimations can be made without scale model tests or on site measurements. 

The Service Tunnel, during the construction period, is densely fitted out with the various services required for the driving process, including water and drainage pipes, power supplies, ventilation ducts, signsdling and communication cables, and twin rail tracks, as indicated in Fig. 9. 

Recent studies have indicated that sophisticated ventilation arrangements are needed to reduce the concentration of styrene below 20 ppm. In hand lay-up work, this is possible by the use of a mobile supply ventilation and exhaust ventilation. In the spray-up work, concentrations below 20 ppm can be achieved by using a booth provided with mobile curtains to reduce the open face area and by maintaining a control velocity of 0.35 m/s. ... 

Design External interfaces Electrical power supply Ventilation supply Discharge/Exhaust ... 

Normal and emergency operation of the RCS requires several support functions to maintain water inventory, purify and treat primary coolant, remove residual heat after a plant shutdown, provide cooling water to pumps and motors, supply ventilation air, and provide... 

Motor end shields are constructed to accept pipe or ducts to supply ventilating air. Air can be supplied from a source remote from the motor, if necessary, to supply clean air for cooling. 

What Beeler did not yet grasp was the very crucial role that a Semco Pinnacle Primary Ventilation System would play in the chilled beam application. The Pinnacle unit utilizes advanced heat wheel technology to dehumidify and precondition supply ventilation air — an important part of the puzzle since chiUed beams handle sensible load only, not latent (humidity) loads. The combination of the two technologies has been successfully applied in facilities throughout the U.S., including the South. 

The changes described above also allowed much easier access to the high voltage cable for routine (6-month) owner directed, service operations, and provided better upper and lower x-ray cabinet and control cabinet ventilation. With the exception of the x-ray tubes, all the individual manufactured components, on all four systems are identical. There are very subtle differences in the warm-up/start-up sequence on the x-ray controllers on the newer systems due to model/year and x-ray tube differences. The last three systems were supplied with environmental type key-boards for the image processors and base-mounted , rather than conduit-mounted exterior warning indicators. The first system was subsequently upgraded to include the better keyboard and the external warning appliances/features. 

Use Equipment Only When deeded. Start morning warm-up no earHer than necessary and do not use outside air for ventilation until the building is occupied. Use minimum amounts of outdoor air according to reference 8. Supply heat at night only to maintain a temperature above 13°C. Supply Heating and Cooling from the Most Efficient Source. 

Diethyl chlorophosphate, supplied by Aldrich Chemical Company, Inc., was used by the submitters without purification and was handled in a glove bag under an atmosphere of dry nitrogen in a well-ventilated hood. The reagent was distilled and stored under nitrogen by the checkers. Aliquots were withdrawn with a syringe as needed. 

As part of a Process Hazards Analysis (PHA). I was required to check a naturally ventilated building containing electrical equipment and a fuel gas supply, for adequate air flow due to thermal forces (stack effect). API RP 500 has a method that they recommend for buildings of l,000fP or less. The building in question was much larger, because ... 

Extent of emergency power supplies for lighting, communication systems, and key items of equipment (e.g. cooling facilities, reactor agitators, exhaust ventilation) and instruments/alarms. 

Use proper ventilation (all the oxygen supply to the torch may not be consumed)... 

Work on high-voltage electrical supply, radioactive equipment, roof work such as checking toxic exhaust from ventilation outlets. 

Changes in room use Is there a need for additional ventilation (supply and/or exhaust) due to increased occupant population or new activities within any area of the building Have new items of equipment (non-HVAQ been provided with local exhaust where needed Look for unusual types or quantities of equipment such as copy machines or computer terminals. 

Note Air distribution systems are not ventilation or air conditioning systems. For example, mixing air distribution and displacement air distribution are methods to bring the supply air to the treated space. 

Alveolar ventilation supplies O2 to the bloodstream while alveolar capillary perfusion provides alveolar gas with COj. Resting individuals consume approximately 250 mL 02/min and produce approximately 200 ml. COi/min because, stoichiometrically, metabolic processes require a greater supply of O, than the quantity of CO2 produced. Defining the respiratory exchange ratio, R, as... 

Ventilation noise originates primarily from fans and the air turbulence generated inside ducts and around supply air and exhaust air terminal devices. The appearance of the noise is, of course, affected by factors such as the speed of rotation and the power of the fan, and by how the fan is stabilized or in other ways acoustically insulated. The noise level and the frequency characteristics are also largely derermined by the velocity of the air inside ducts and around terminal devices, where factors such as the dimensions and appearance of the ducts and terminal devices may play a decisive role in the appearance of the noise. 

The noise from the fan is propagated in the duct to the openings inwards or outwards in the premises. The ventilation noise often propagates into the surrounding area from the supply air and exhaust air terminal units in the rooms. The ducts in themselves may also be important sources of noise, particularly if they are poorly insulated or otherwise designed in such a way that noise generation may occur. 

Efforts to reduce the noise from a ventilation system may be concentrated on measures concerning the fan, the fan room, the fan ducts, and the supply and exhaust air terminals. - ... 

Balanced mechanical supply and exhaust ventilation equipped with an advanced air distribution strategy to accurately control the flow patterns in a work space... 

Forced convection or supply air jets introduced into the room by mechanical or natural ventilation systems, or their combination (Section 7.4) ... 

The value of the coefficient of turbulent diffusion, D, depends upon the air change rate in the ventilated space and the method of air supply. Studies by Posokhin show that approximate D values for locations outside supply air jets is equal to 0.025 m-/s. Air disturbance caused by operator or robot movement results in an increase in the D value of at least two times. Studies by Zhivov et al. showed that the D value is affected by the velocity and direction of cross-drafts against the hood face, and the presence of an operator e.g., for a cross-draft directed along the hood face with velocity u = 0.5 m/s with D = 0.15 m-/s (with the presence of an operator), an increase to = 1.0 m/s results in D = 0.3 m-/s. 

The p coefficient value depends upon the supply air method (e.g., p = 0 with displacement and natural ventilation, P = 1 with convective plume dissipating within the occupied zone due to interaction with supply jets, airflows created by moving objects, etc.). 

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