SAFEX Fog Generator Systems

Transcription

1 SAFEX Fog Generator Systems Safe seeding for Flow visualisation and LDA applications Applications For the investigation of gas flows by means of Flow Visualisation Laser Doppler Anemometry the SAFEX fog generator systems produce suitable tracer particles. Features Small and portable devices High safety standard Non-hazardous fog fluids Variable fog output quantity Variable fog durability 2 years warranty Introduction The investigation of gas flows frequently comprises flow visualization as one of the first steps to get insight into flow processes. Flow vizualisation is used in many cases to locate regions of special interest for further detailed analysis by means of e.g. Laser Doppler Anemometry or Particle Image Velocimetry. The SAFEX Fog Generators are powerful, yet small devices. A white, dense fog which is non-irritant, nonflammable and non-hazardous is generated by evaporation and condensation of a water-based fog liquid. The mean droplet size in the fog is around 1 µm and the durability of the fog can be controlled through the choice of different fog fluids. SAFEX Fog Generators are used for applications where a large volume has to be quickly filled with fog as well as for applications where only a small fog quantity has to be injected locally.

2 Product Information SAFEX Fog Generator Systems Fog generator types: Injection nozzle types FOG 2010 The system of choice for the majority of applications. The fog output quantity can be adjusted remotely by using one of two available remote control units or directly at the fog generator. 195 SG-D Some applications require an extremely large fog quantity. This device provides the highest but still controllable fogging power. Fog Probe NS3 This fog probe system with a probe length of 1010 mm is especially developed and optimized for flow field visualization in wind tunnels where seeding of discrete streaklines is required. Fog output variability allows adaptation to various flow speeds. Different probe nozzles are available to minimize pulsations at various air speeds (0.6/1 mm for low speeds, 2 mm for higher speeds). The flexible connection between the probe and the supply unit makes it very easy to use. Multiple fog probes can be combined in a common mount to form a fog rake. Fog Fluids The durability of the fog can be varied through the choice of different fog fluids, but also depends on the ambient temperature and relative humidity. Typical fog durability (in confined areas) with the different fog fluid types is: Blitz (for quickly disappearing fog): Standard (standard type): Extra Clean 5-10 min min min. Accessories Tube adapter and flexible tube: to guide the fog over longer distances Remote quantity control: for remote activation of fog generation and variation of fog quantity Remote fog control: as above but with additional variable timer functions for interval operation Fog injection nozzles: (for FOG 2010 only) a selection of different small diameter (6 mm) screw-on fog injection nozzles (100/200 mm long) is available to facilitate fog injection into confined flows Note: Fog injection nozzles become hot ( C) during operation Heating Power (W) (ml/min) Fog Fluid Consumption min - max Supply Voltage (V) FOG / SG-D Fog Probe NS3 Ordering information Safex Fog Generators and accessories 10D15 FOG 2010 (220 V) 10D25 FOG 2010 (110 V) 10D SG-D (220 V) 10D11 Tube Adaptor 10A10 Flexible Tube 10A20 Cable extension 5 m for remote control 10A51 Fog injection nozzle, bow, 6/200 10A52 Fog injection nozzle, straight, 6/200 10A53 Fog injection nozzle, hook, 6/100/100 10A54 Fog injection nozzle, right angle, 6/200 10B20 Remote Quantity Control 8-pole (220 V) 10B30 Remote Fog Control (220 V) 10B50 Remote Quantity Control 8-pole (110 V) 10B60 Remote Fog Control (110 V) Safex Fog Probe system and accessories 10D50 10A61 10A62 10A63 10A64 10A65 10A66 10T10 10T20 10T40 Fog Probe system NS3 (incl. 10A45) NS3 Probe nozzle, 0.6 mm, straight NS3 Probe nozzle, 0.6 mm, bent 90 NS3 Probe nozzle, 1 mm, straight NS3 Probe nozzle, 1 mm, bent 90 NS3 Probe nozzle, 2 mm, straight NS3 Probe nozzle, 2 mm, bent 90 Fog Fluids Blitz Standard Extra Clean The specifications in this document are subject to change without notice. Publication No.: pi_173_v7

3 Product Information SAFEX Fog Generator Systems

4 Liquid Seeder, 10 Bar Back pressure Seeding Generator for LDA and PIV Applications Droplet Seeding for Particle Image Velocimetry Droplet Seeding for Laser Doppler Anemometry Oil mist for flow visualisation Features Up to 10 bar working back-pressure Ten Laskin nozzles Remote Control Panel Quick re-fill operation without the need to stop experiment Introduction This seeding generator produces droplets ideal for PIV and LDA measurements. It is the preferred solution for small to medium size facilities, and where remote control is required. Ten identical Laskin nozzles at the base of the device can be operated independently to give an easily controlled and repeatable seed density. Further dilution of the seed is made possible by means of an additional dilution jet that bypasses the liquid and mixes with the emerging mist. The individual Laskin nozzles operate close to sonic conditions at typical air supply pressures. The high shear region between the emerging air and liquid atomises and entrains microscopic liquid droplets into bubbles which release the seed on bursting at the free surface. Bubble bursting is a source of secondary atomisation that gives larger droplets, which are prevented from exiting the seeder by the horizontal baffle plate at the top of the device

5 Liquid Seeder, 10 Bar Back Pressure Product Information Specifications Up to 10 bar working back-pressure Ten Laskin nozzles Approximate 10 8 particles/second seed output per jet Particle size range : 1-3 µm Stainless steel pressure vessel construction. Acrylic level indicator rated for 10 bar max pressure. Dilution air : Variable through central tube Remote Panel : Pneumatically operate any number of nozzles (1-10) to control seed density remotely from the experiment. Compatible with solenoid valves for PLC or computer control. Push-fit pipe connectors and colour coded air tubes for easy installation and adjustment of remote cable length. One way valves on all Laskin nozzles to avoid contamination of air supply pipes with seeding liquid. M6 tapped mounting holes Quick re-fill operation without the need to stop experiment Additional information For additional information please contact your Dantec Dynamics representative in your country. Please find a list of current representatives on Dantec Dynamics web site ( Ordering information Model 9010F0021 Liquid seeder, 10 bar back pressure, remote control The specifications in this document are subject to change without notice. Recommended working liquids Typical seed materials include corn oil, olive oil, and silicone fluids (eg Dow Corning). Corn oil is frequently used in wind tunnel applications at atmospheric pressures and temperatures, as it is inexpensive and produces micron-sized droplets. Olive oil has a higher flash point or decomposition temperature, and is the liquid of choice for many internal combustion engine flows. Where operation at very high temperatures, and reduced pressures is required, silicone vacuum fluids are preferred. These liquids were developed for use in vacuum diffusion pumps and combine very low vapour pressure with high flash points and surface tension and kinematic viscosities similar to the vegetable oils. It is also possible to use this seeder to provide solid particle seeding by diluting powders with water or methanol. Publication No.: pi_128_v7

6 Seeding particles For flow visualisation, LDA and PIV Applications For flow investigations by means of Flow Visualisation, Laser Doppler Anemometry and Particle Image Velocimetry Features Optimum seeding for a wide range of applications Fluorescent particles give improved vector maps from PIV applications close to walls or through dirty windows Fluorescent particles enable simultaneous two-phase measurements with PIV (liquid-gas, liquid-solid) Non-toxic materials Introduction The application of optical flow measurement techniques to gas and liquid flows usually requires artificial seeding of the flow. Depending on the optical configuration and the overall conditions, tracer particles must fulfill different requirements. Results can be considerably improved by careful selection of the seeding material. PSP: Polyamide Seeding Particles are produced by polymerisation processes and therefore have a round but not exactly spherical shape. These microporous particles are highly recommendable for water flow applications. HGS, S-HGS: Hollow Glass Spheres and Silver Coated Hollow Glass Spheres are borosilicate glass particles with a spherical shape and a smooth surface, preferrably for liquid flow applications. A thin silver coating further increases the reflectivity. FPP: Fluorescent Polymer Particles are based on melamine resin. The fluorescence dye is homogeneously distributed over the entire particle volume. In applications with a high background light level, fluorescent seeding particles can improve the quality of vector maps from PIV and LDA measurements significantly. The receiving optics must be equipped with a filter centered around the emission wavelength. 1

7 Seeding particles For flow visualisation, LDA and PIV Ordering information PSP, Polyamide Seeding Particles 80A3011 PSP-5, diam. 5 µm, 250 g 80A4011 PSP-20, diam. 20 µm, 250 g 80A5011 PSP-50, diam. 50 µm, 250 g HGS, Hollow Glass Spheres 80A6011 HGS-10, mean diam. 10 µm, 250 g S-HGS, Silver Coated Hollow Glass Spheres 80A7001 S-HGS-10, mean diam. 10 µm, 100 g FPP, Fluorescent Polymer Particles Excitation max.: 550 nm Emission max.: 590 nm 80A8301 PMMA-RHB-10, 1-20um, 200 ml water suspension (50 g particles) 80A8311 PMMA-RHB-10, 1-20um, 400 ml water suspension (100 g particles) 80A8401 PMMA-RHB-35, 20-50um, 200 ml water suspension (50 g particles) 80A8411 PMMA-RHB-35, 20-50um, 400 ml water suspension (100 g particles) Specifications Mean diameter (µm) PSP Polymid Seeding Particles HGS Hollow Glass Spheres S-HGS Silver Coated Hollow Glass Spheres FPP Fluorecent Polymer Particles Size distribution 1-10 µm 5-35 µm µm Particle shape Non-spherical but round Selection of seeding particles 2-20 µm 2-20 µm 1-20 µm µm µm spherical spherical spherical Density (g/cm 3 ) Melting point ( C) Refractive index Material Polymide 12 Borosilicate glass Borosilicate glass Melamine resin based polymer LDA Flow visualisation, PIV Gas flows SAFEX fog generator * Liquid Seeding Generator* High Volume Liquid Seeding Generator* Powder Seeder (for combustion experiments)* Liquid flows PSP Polyamide Seeding Particles PSP Polyamide Seeding Particles HGS Hollow Glass Spheres S-HGS Silver Coated Hollow Glass Spheres FPP Fluorescent Polymer Particles * for details see separate product information. The specifications in this document are subject to change without notice. 2 Publication no: pi_199_v5