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34-591: The construction was commissioned by Johann Evangelist Zacherl, son of the industrial magnate Johann Zacherl , who built the Zacherlfabrik . It was one of the first modern buildings erected at the Wildpretmarkt in Vienna's city centre. The façade is made of polished grey granite plates; the artistically executed cornice is also noteworthy. The figure of Archangel Michael on the façade is the work of Ferdinand Andri , while

68-404: A carpet-cleaning machine "distributing over the cleansed carpet the insecticide to guard it against the attack of moth" in 1882, a Pyrethrum Soap, and a tincture for destroying insects . According to Hiscox, the insecticide was obtained as follows: The powder is obtained by brushing the dried flowers of the pellitory (pyrethrum). The leaves, too, are often used. (...) The active principle

102-417: A controlled small drop size over a range of operation. Each nozzle has a performance curve, and the liquid and gas flow rates determine the drop size. Excessive drop size can lead to catastrophic equipment failure or may have an adverse effect on the process or product. For example, the gas conditioning tower in a cement plant often utilizes evaporative cooling caused by water atomized by two-fluid nozzles into

136-441: A high viscosity require a higher minimum pressure to begin spray pattern formation and yield narrower spray angles compared to water. The surface tension of a liquid tends to assume the smallest possible size, acting as a membrane under tension. Any portion of the liquid surface exerts a tension upon adjacent portions or upon other objects that it contacts. This force is in the plane of the surface, and its amount per unit of length

170-476: A liquid other than water is on the capacity of the spray nozzle. All vendor-supplied performance data for nozzles are based on spraying water. To determine the volumetric flowrate Q, of a liquid other than water the following equation should be used. Dynamic viscosity is defined as the property of a liquid that resists change in the shape or arrangement of its elements during flow. Liquid viscosity primarily affects spray pattern formation and drop size. Liquids with

204-595: A longer stay in Tiflis, in 1855 he established his company, Mottenfraß-Versicherungsunternehmung Johann Zacherl , in Vienna's 19th district , and began selling the insect repellent Zacherlin . With the help of his son, Johann Evangelist, he developed the Pyrethrum product line. Zacherl died in Vienna , Austria in 1888. Zacherl developed an effective, all-natural moth insecticide made from Pyrethrum blossoms. He agreed with

238-478: A multiple outlet nozzle is known as a compound nozzle. Multiple outlets on nozzles are present on spray balls, which have been used in the brewing industry for many years for cleaning casks and kegs. Spray nozzles range from those for heavy duty industrial uses to light duty spray cans or spray bottles . Single-fluid or hydraulic spray nozzles utilize the kinetic energy imparted to the liquid to break it up into droplets. This most widely used type of spray nozzle

272-413: A nozzle for a process that is drop size sensitive. Liquid temperature changes do not directly affect nozzle performance, but can affect viscosity, surface tension, and specific gravity, which can then influence spray nozzle performance. Specific gravity is the ratio of the mass of a given volume of liquid to the mass of the same volume of water. In spraying, the main effect of the specific gravity Sg of

306-405: A spiral to yield a spiral shaped sheet approximating a full cone spray pattern or a hollow-cone spray pattern. The spiral design generally produces a smaller drop size than pressure swirl type nozzle design, for a given pressure and flow rate. This design is clog resistant due to the large free passage. Common applications include gas scrubbing applications (e.g., flue-gas desulfurization where

340-493: Is a type of nozzle in which several individual single or two fluid nozzles are incorporated into one nozzle body, as shown below. This allows design control of drop size and spray coverage angle. Two-fluid nozzles atomize by causing the interaction of high velocity gas and liquid. Compressed air is most often used as the atomizing gas, but sometimes steam or other gases are used. The many varied designs of two-fluid nozzles can be grouped into internal mix or external mix depending on

374-429: Is better suited to higher viscosity streams. Many compound internal-mix nozzles are commercially used; e.g., for fuel oil atomization. External mix nozzles contacts fluids outside the nozzle as shown in the schematic diagram. This type of spray nozzle may require more atomizing air and a higher atomizing air pressure drop because the mixing and atomization of liquid takes place outside the nozzle. The liquid pressure drop

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408-413: Is indicated by an increase in nozzle capacity and by a change in the spray pattern, in which the distribution (uniformity of spray pattern) deteriorates and increases drop size. Choice of a wear-resistant material of construction increases nozzle life. Because many single fluid nozzles are used to meter flows, worn nozzles result in excessive liquid usage. The material of construction is selected based on

442-467: Is lower for this type of nozzle, sometimes drawing liquid into the nozzle due to the suction caused by the atomizing air nozzles (siphon nozzle). If the liquid to be atomized contains solids an external mix atomizer may be preferred. This spray may be shaped to produce different spray patterns. A flat pattern is formed with additional air ports to flatten or reshape the circular spray cross-section discharge. Many applications use two-fluid nozzles to achieve

476-428: Is more energy efficient at producing surface area than most other types. As the fluid pressure increases, the flow through the nozzle increases, and the drop size decreases. Many configurations of single fluid nozzles are used depending on the spray characteristics desired. The simplest single fluid nozzle is a plain orifice nozzle as shown in the diagram. This nozzle often produces little if any atomization, but directs

510-407: Is not a volatile oil, as stated by some writers, but a rosin , which can be dissolved out from the dry flowers by means of ether . The leaves also contain this rosin but in. smaller proportions than the flowers. Tincture of pyrethrum is made by infusing the dried flowers in five times their weight of rectified spirit of wine . Diluted with water it is used as a lotion. (...) The dust resulting from

544-455: Is surface tension. The value for water is about 0.073 N/m (0.0050 lb f /ft) at 21 °C (70 °F). The main effects of surface tension are on minimum operating pressure, spray angle, and drop size. Surface tension is more apparent at low operating pressures. A higher surface tension reduces the spray angle, particularly on hollow cone nozzles. Low surface tensions can allow nozzles to be operated at lower pressures. Nozzle wear

578-426: Is very useful for high transfer efficiency. Examples are the industrial spraying of coatings (paint) and applying lubricant oils. The charging is at high voltage (20–40 kV) but low current. Almost all drop size data supplied by nozzle manufacturers are based on spraying water under laboratory conditions, 21 °C (70 °F). The effect of liquid properties should be understood and accounted for when selecting

612-511: The atlantes were designed by Franz Metzner . The oval-shaped stairwell features a lamp that resembles an insect; this is a reference to insecticide, the production of which had made the Zacherl family rich. In 1949, it was necessary to restore the Zacherlhaus after it had been damaged during World War II . Today, the Zacherlhaus is a listed building . It is one of the most important examples of

646-457: The chiefs of the villages to collect the flowers and ship them to Tiflis. He then ground the dried blossoms into powder, filled bags with it, and put them in sheep leathers for transport to Europe. He continued importing dried heads of Chrysanthemum Cinerariifolum and Chrysanthemum Coccineum directly from Tifflis until 1870, when he began producing it locally. His insecticide powder was called Zacherlin . He developed other products, including

680-469: The configurations of the solid cone spray nozzle is shown in a schematic diagram. A swirling liquid motion is induced with the vane structure, however; the discharge flow fills the entire outlet orifice. For the same capacity and pressure drop, a full cone nozzle will produce a larger drop size than a hollow cone nozzle. The coverage is the desired feature for such a nozzle, which is often used for applications to distribute fluid over an area. A compound nozzle

714-425: The cost of creating additional surface area. A wide variety of spray nozzles exist, that make use of one or multiple liquid breakup mechanisms, which can be divided into three categories: liquid sheet breakup, jets and capillary waves. Spray nozzles are of great importance for many applications , where the spray nozzle is designed to have the right spray characteristics . Spray nozzles can have one or more outlets;

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748-433: The dust laden gas. If drops do not completely evaporate and strike a vessel wall, dust will accumulate, resulting in the potential for flow restriction in the outlet duct, disrupting the plant operation. Rotary atomizers use a high speed rotating disk, cup or wheel to discharge liquid at high speed to the perimeter, forming a hollow cone spray. The rotational speed controls the drop size. Spray drying and spray painting are

782-461: The flow to spread out on the axis of the V notch. A flat fan spray results which is useful for many spray applications, such as spray painting. A surface impingement nozzle causes a stream of liquid to impinge on a surface resulting in a sheet of liquid that breaks up into small drops. This flat fan spray pattern nozzle is used in many applications ranging from applying agricultural herbicides to painting. The impingement surface can be formed in

816-624: The fluid properties of the liquid that is to be sprayed and the environment surrounding the nozzle. Spray nozzles are most commonly fabricated from metals, such as brass , Stainless steel , and nickel alloys , but plastics such as PTFE and PVC and ceramics ( alumina and silicon carbide ) are also used. Several factors must be considered, including erosive wear, chemical attack, and the effects of high temperature. Automotive coating: Automotive coating demands droplets 10–100  μm (0.39–3.94 mils ) in size uniformly deposited on substrate. Applications of spray technology are more pronounced during

850-406: The mixing point of the gas and liquid streams relative to the nozzle face. Internal mix nozzles contact fluids inside the nozzle; one configuration is shown in the figure below. Shearing between high velocity gas and low velocity liquid disintegrates the liquid stream into droplets, producing a high velocity spray. This type of nozzle tends to use less atomizing gas than an external mix atomizer and

884-574: The most important and common uses of this technology. They can also be automatic. This type of spray nozzle utilizes high frequency (20–180 kHz) vibration to produce narrow drop-size distribution and low velocity spray from a liquid. The vibration of a piezoelectric crystal causes capillary waves on the nozzle surface liquid film. An ultrasonic nozzle can be key to high transfer efficiency and process stability as they are very hard to clog. They are particularly useful in medical device coatings for their reliability. Electrostatic charging of sprays

918-476: The office building Zacherlhaus in Vienna's Innere Stadt from 1903 to 1905. It includes a row of atlantes along the cornice line by sculptor Franz Metzner . Atomizer nozzle A spray nozzle or atomizer is a device that facilitates the dispersion of a liquid by the formation of a spray . The production of a spray requires the fragmentation of liquid structures, such as liquid sheets or ligaments, into droplets, often by using kinetic energy to overcome

952-424: The perimeter of the outlet orifice producing a characteristic hollow cone spray pattern. Air or other surrounding gas is drawn inside the swirl chamber to form an air core within the swirling liquid. Many configurations of fluid inlets are used to produce this hollow cone pattern depending on the nozzle capacity and materials of construction. The uses of this nozzle include evaporative cooling and spray drying. One of

986-485: The polychromed brick building with pointed arches, two minarets and a dome was one of Vienna's most recognized structures. Since the collapse of the Zacherl company, the building has been used as a warehouse for carpets, furs and textiles. Today, it is used for art exhibitions and symposiums, in association with the contemporary art exhibitions Position:Gegenwart at Jesuit's Church of Vienna. Zacherl's son, Johann Evangelist Zacherl, commissioned Jože Plečnik to build

1020-411: The smaller droplets often offer superior performance) and fire fighting (where the mix of droplet densities allow spray penetration through strong thermal currents). Pressure-swirl spray nozzles are high-performance (small drop size) devices with one configuration shown. The stationary core induces a rotary fluid motion which causes the swirling of the fluid in the swirl chamber. A film is discharged from

1054-399: The stream of liquid. If the pressure drop is high, at least 25 bars (2,500 kPa; 360 psi), the material is often finely atomized, as in a diesel injector. At lower pressures, this type of nozzle is often used for tank cleaning, either as a fixed position compound spray nozzle or as a rotary nozzle. The shaped orifice uses a semi spherical shaped inlet and a V notched outlet to cause

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1088-517: The use of insect powder sometimes proves irritating to the mucous membranes of the one applying the powder. This is best avoided by the use of a spray atomizer . Zacherlin's packaging showed a cossack with a high cap and an atomizer in hand, a marketing strategy that proved very successful. The insecticide factory in Döbling was designed by the architect Hugo von Wiedenfeld and constructed by Karl Mayreder in 1888–1892. Explicitly oriental in style,

1122-544: The work of the Otto Wagner -school. It belongs to Johann Zacherl's descendants and is used as office space. 48°12′36″N 16°22′18″E  /  48.21000°N 16.37167°E  / 48.21000; 16.37167 Johann Zacherl Johann Zacherl (1814 – 30 June 1888) was an Austrian inventor, industrialist and manufacturer who made a fortune in the late 19th century selling dried flower heads of Chrysanthemum cinerariifolium as an insecticide . Zacherl

1156-605: Was born in Munich (Germany) in 1814. After finishing his studies, he left Munich to visit Vienna , St Petersburg and Odessa . He eventually reached Tiflis in the Caucasus , where he discovered villagers used a natural insecticide, Pyrethrum, against vermin . He began to develop the powder's trade with Austria in 1842. The powder received different names: Lowizachek (in Armenia), Bug Flower, Powder of Persia and Persian insect powder. After

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