Nozzles output

The factors of walking or tractor speed, nozzle output, pump pressure, and width of treatment can be altered to provide the most accurate application method. As a preference, it is suggested that the output of the nozzles be set to the manufacturer s recommended output, and the speed of walking or driving be adjusted up or down to achieve the desired application rate. 

Nozzle output is influenced by operating pressure, so, with manually operated pumps on basic lever-operated knapsack sprayers, the pressure will vary... 

In view of these variations, the calibration of equipment should be done by individual users under the conditions in which they will apply the pesticide. Measurement of each of the three factors (nozzle output, swath and speed) can be measured and the volume application rate calculated using the formula ... 

The AeroSizer, manufactured by Amherst Process Instmments Inc. (Hadley, Massachusetts), is equipped with a special device called the AeroDisperser for ensuring efficient dispersal of the powders to be inspected. The disperser and the measurement instmment are shown schematically in Figure 13. The aerosol particles to be characterized are sucked into the inspection zone which operates at a partial vacuum. As the air leaves the nozzle at near sonic velocities, the particles in the stream are accelerated across an inspection zone where they cross two laser beams. The time of flight between the two laser beams is used to deduce the size of the particles. The instmment is caUbrated with latex particles of known size. A stream of clean air confines the aerosol stream to the measurement zone. This technique is known as hydrodynamic focusing. A computer correlation estabUshes which peak in the second laser inspection matches the initiation of action from the first laser beam. The equipment can measure particles at a rate of 10,000/s. The output from the AeroSizer can either be displayed as a number count or a volume percentage count. 

A gas turbine used in aircraft must be capable of handling a wide span of fuel and air flows because the thmst output, or pressure, covers the range from idle to full-powered takeoff. To accommodate this degree of flexibiUty in the combustor, fuel nozzles are usually designed with two streams (primary and secondary flow) or with alternate tows of nozzles that turn on only when secondary flow (or full thmst power) is needed. It is more difficult to vary the air streams to match the different fuel flows and, as a consequence, a combustor optimized for cmise conditions (most of the aircraft s operation) operates less efficiently at idle and full thmst. 

The resulting motion of the beam is detected by the pneumatic nozzle amphfier, which, by proper sizing of the nozzle and fixed orifice diameters, causes the pressure internal to the nozzle to rise and fall with vertical beam motion. The internal nozzle pressure is routed to the pneumatic relay. The relay, which is constructed like the booster relay described in the Valve Control Devices subsection, has a direct hnear input-to-output pressure characteristic. The output of the relay is the controller s output and is piped away to the final control element. 

Head meters with density compensation. Head meters such as orifices, venturis, or nozzles can be used with one of a variety of densitometers [e.g., based on (a) buoyant force on a float, (b) hydrauhc couphug, (c) voltage output from a piezoelectric ciystal, or (d) radiation absolution]. The signal from the head meter, which is proportional to pV" (where p = fluid density aud V = fluid velocity), is multiphed by p given by the densitometer. The square root of the produc t is proportional to the mass flow rate. 

The uniformity of the eombustor outlet profile affeets the useful level of turbine inlet temperature, sinee the average gas temperature is limited by the peak gas temperature. This uniformity assures adequate nozzle life, whieh depends on operating temperature. The average inlet temperature to the turbine affeets both fuel eonsumption and power output. A large eombustor outlet gradient will work to reduee average gas temperature and eonse-quently reduee power output and effieieney. Thus, the traverse number must have a lower value—between 0.05 and 0.15 in the nozzle. 

Underreamer Hydraulics. Pressure losses across the underreamer nozzles (orifice) are shown in Figures 4-178 and 4-179 [58]. The shaded area represents the recommended pressure drop required for cutters to fully open. These pressure drop graphs can be used for pressure losses calculations (given pump output and nozzles) or for orifice (nozzle) selection (given pump output and pressure loss required). 

In the cases where liquid formulations are applied, calibration is normally performed by collecting the output volume over a given time period. Generally a minimum of three such measurements should be taken in order to estimate output consistency. Where output is collected from multiple nozzles or outlets, each nozzle or outlet should be evaluated in order to ensure uniformity of output across all the nozzles or outlets. If the deviation from the manufacturer s recommended value is not within 5% (or the value specified in an appropriate SOP), the nozzle or outlet should be replaced. The use of a patternator allows the droplet distribution pattern of the nozzles or outlets to be measured accurately, and this check should be conducted annually. Having estimated the output of the equipment, the time required to treat a specific area with a known quantity of test item solution can be calculated. 

Recently, a revival of electron ionisation LC-MS has been proposed by development of LC-SMB-MS [529]. In this system, the LC output (50-250 p,Lmin 1) is vaporised at atmospheric pressure and expanded from a supersonic nozzle into the vacuum system... 

Washout Solution of Automatic Processor Washout water is sprayed through 55 nozzles of 1/4 inch diameter under an optimum condition of nozzle pressure of 6 kg/cm2, recirculated at 200 lit/min., upward spray power to spout water for 80 meters, output of 7.5 kw, and the water temperature of about 45°C. The washout speed under these conditions is about 20 seconds per 0.1 mm depth of relief. (See Fig. 8). 

Pressure nozzles are somewhat inflexible since large ranges of flowrate require excessive variations in differential pressure. For example, for an atomiser operating satisfactorily at 275 kN/m2, a pressure differential of 17.25 MN/m2 is required to increase the flowrate to ten times its initial value. These limitations, inherent in all pressure-type nozzles, have been overcome in swirl spray nozzles by the development of spill, duplex, multi-orifice, and variable port atomisers, in which ratios of maximum to minimum outputs in excess of 50 can be easily achieved(34). 

What I wish to achieve is to maintain the same horsepower output from the turbine. But at the same time, I want to force open the governor speed-control valve, raise the pressure in the steam chest, but decrease the steam flow through the steam nozzle. The only way this can be done is to make the nozzle smaller. 

Differential pressure transmitters (or DP cells) are widely used in conjunction with any sensor that produces a measurement in the form of a pressure differential (e.g. orifice plate, venturi meter, flow nozzle, etc.). This pressure differential is converted by the DP cell into a signal suitable for transmission to a local controller and/or to the control room. DP cells are often required to sense small differences between large pressures and to interface with difficult process fluids. Devices are available that provide pneumatic, electrical or mechanical outputs. 

A typical DP cell is shown in Fig. 6.19a<23). The associated flapper/nozzle system works on a force-balance principle (see Volume 1, Section 6.2.3). The output pressure P0 is linearly related to the difference in pressure (P, - P2), thus ... 

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