Air inlet system

Provide fresh air. For maximum effect, a ducted fresh-air inlet system will provide cool air in summer and, if fitted with a recirculation unit, allow a flow of tempered or warm air in winter. The air outlet should be positioned to ensure that the airflow does not cause a draft on the back of the neck. 

Figure 4-4 shows a typical system under positive pressure. It differs from the vacuum system in that the material enters from one source and is distributed directly to several tanks. In this case no cyclone separator is used the air laden with solids enters the process bins directly. The decrease in velocity of the stream and its change in direction will cause most of the solids to drop out. For this system each receiver must have a filter to remove the remaining solids. Note that the blower is placed at the air entrance, instead of after the filter as in the vacuum system. Should a bag in the fiber filter break, no dust will get into the blower or its motor. Another advantage is that no contaminants from the atmosphere can enter the system when it is under positive pressure, except through the air inlet system. 

Some applications pursued for the ABS/Polyamide blends are xmpainted automotive interior parts, center consoles, steering wheel covers, air inlet systems. 

It is almost imiversaUy agreed that stainless steel is the most cost-effective longterm solution for construction of the air-inlet system. The premium between stainless steel over painted carbon steel can now be as low as 20%, whereas there are no further painting costs and the life is infinitely longer. 

The hexapole cannot act as a mass filter by applying a DC field and is used only in its all-RF mode, in which it allows all ions in a beam to pass through, whatever their m/z values. In doing so, the ion beam is constrained, so it leaves the hexapole as a narrow beam. This constraint is important because the ion beam from the inlet system tends to spread due to mutual ion repulsion and collision with residual air and solvent molecules. By injecting this divergent beam into a hexapole unit, it can be refocused. At the same time, vacuum pumps reduce the background pressure to about 10 mbar (Figure 22.1). The pressure needed in the TOF analyzer is about 10 ... 

The ammonia—air dilution system dilutes the vaporized ammonia by a factor of 20 to 25 with air for better admixing through the AIG and to prevent explosive ammonia—air mixtures. Once the catalyst volume is selected, the NO removal is set by the NH /NO mole ratio at the inlet of the SCR system (39). 

Combination of evaporative and refrigerated inlet systems—The use of evaporative coolers to assist the chiller system to attain lower temperatures of the inlet air. 

Figure 2-36. Meohanioal refrigerated inlet system used to oool the inlet air of the gas turbine.

The prime design objeetive of the filter system is to proteet the gas turbine. The performanee of the gas turbine inlet-air filter system has important and far-reaehing influenees on overall maintenanee eosts, reliability, and availability of gas turbines. There are three major results of improper air filtration (1) erosion, (2) fouling of the axial-flow eompressor, and (3) eorrosion of the gas turbine hot-gas path inlets. The importanee of the inlet-air filter, as it relates to eaeh of these three phenomena, ean be appreeiated if... 

System designers often think dampers bloek airflow and are suitable to prevent baek drafts in idle towers. This is not the ease. Airfoil dampers simply hamper fan housing efficiency- they do not block airflow. Air Inlet Screens are always part of blow through, counterflow towers to protect people from rotating equipment. Some designs can be a hazard when accessible from the underside and require the specifier to call out additional screening. They can be a worthwhile accessory when there are nearby trees even when not required for safety reasons. Air inlet screens should be eliminated on towers utilizing inlet ductwork. Inlet ductwork may also make it necessary to block extraneous air entry such as from the underside when towers are elevated. 

Air Inlet That portion of the cooling tower structure in which air is drawn into the system. 

Low-momentum air supply systems designed for local ventilation purposes mainly use vertically downward airflow. Some systems with an inlet of low-momentum horizontal airflow for a whole workroom are on the borderline between general and local ventilation and are therefore briefly described here. A more complete description will be found in chapters 7 and 8 dealing with general ventilation. 

Forced convective Far convectors These units give a high heat output for volume of space occupied by the unit, together with the ability to distribute the heat over a considerable area using directional grilles. May be used to bring in heated fresh air for room ventilation. Rapid response to conhol by individual thermostat. By use of variable speed motors rapid warm-up available in intermittent systems Altered fresh air inlet facility. Electric supply required to each individual unit. 2 to 25 kW. 

Unit heaters A unit with a large propeller or cenhifugal fan to give high air volume and wide throws. Louvers direct the air flow in the direction required. May be ceiling mounted, discharging vertically or horizontally or floor mounted. Can be used with fresh air Rapid response to conhol by individual thermostat by use of multi-speed motors rapid warm-up available on intermittent systems Altered fresh air inlet facility. Electric supply required for each individual unit. 3 to 300 kW. 

A vacuum system like that shown in Figure 4-3 will be used,36 since delivery to a single receiver is desired. For this system there will be 100 ft of horizontal pipe and 35 ft of vertical pipe. The pressure drop across the air filter at the air inlet should be about 0.5 in. H20 and that across the receiver should be negligible. The pressure drop across the fabric filter is 4.0 in.H20 and across the receiver is 3 in H20. 

Any problems in the setup, startup, and operation of the CBMS also were recorded in the course of the field tests. These observations are important to improving the system before it goes into production. The field tests revealed three problems. The protective screens over electronics cooling air inlets and outlets on the CBMS II housing were damaged by operator activities in the vehicles and required reinforcement. The ground probe head, which protrudes outside the vehicle hull, required more power to maintain the correct temperature under colder or wetter weather conditions. Finally the automated mass and frequency calibration procedure was not reliable in the field and required modification. These problems have been corrected and are being incorporated in the LRIP units. 

The charcoal beds must be thermally isolated from each other. The air inlets must be positioned far enough apart so as to minimize feedback of clean air back into the system. To prevent the accumulation of radon in the house in the event of a valve failure, all valves should be provided with backups. The volume of air cleaned per unit mass of carbon increases exponentially with decreasing temperature (Kapitanov et al., 1967). Thus greatly increased adsorption capacity can be obtained by cooling the carbon below ambient temperature. Although this process will require additional energy input, it may be worthwhile to consider some form of cooling. 

To assist in the location of air inlets for ventilation systems and combustion equipment... 

Aliphatic alcohols show a strong tendency to thermally eliminate a water molecule. This is of special relevance if volatile alkanols are introduced via the reference inlet system or by means of a gas chromatograph. Then, the mass spectra correspond to the respective alkenes rather than to the alkanols that were intended to be analyzed. The water is often not detected, simply because mass spectra are frequently acquired starting from m/z 40 to omit background from residual air. 

Alternatively stated, the losses for the atomizer solids residue particles in a complete single pass is 80%. This is reasonable because this particular air washer system had good inlet filtration media. 

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