A fountain type ultrasonic atomizer was chosen to be a possible device to be used to assist in the alleviation of global warming. Atomization of seawater by an ultrasonic atomizer will enhance more cloud condensation nuclei; as a result, more UV radiation will be reflected back into the space. There are two crucial spray characters: droplet size and the number of droplets. The droplet size needs to be in a certain size range, so that they can stay in the atmosphere. The number of droplets needs to be as high as possible; the more cloud nuclei, the more UV radiation is reflected. The characteristics of sprays are affected by many parameters: liquid properties and the atomizer design. In this study, we characterized two different atomizers: one with a fixed frequency atomizer at 1.72 MHz and one with adjustable frequency and voltage atomizer with a calculated resonant frequency of 2.24 MHz. In addition for the fixed atomizer, different liquid media: tap water (20° C), hot water (46° C), cold water (14° C) and salt waters with different percents salinity (2% - 3.5% by volume), were studied. A Phase Doppler Anemometer was used to measure the characteristics of sprays: droplet velocity, droplet size and number of droplets in a required size range. It was found that the droplet velocity is barely affected by the liquid properties and liquid depth except for the hot water. The relatively high temperature liquid appears to alter the characteristics of the piezo disk; in addition, the inconsistent temperature could vary the characteristics of the spray. The droplet size is strongly dependent on liquid properties and frequency of vibration. The number of droplets is obviously affected by liquid properties and atomizer designs; there is not yet a known correlation between the number of droplets and other parameters. A theoretical study was undertaken in order to compare predicted acoustic properties of acoustic waves with the measured number of droplets generated. The mathematical model was constructed based on applying boundary conditions to a general 2- Dimensional wave equation in cylindrical coordinates. The predicted results satisfy the boundary conditions very well. Since we deal with high frequency acoustic waves, the number of wave modes used in the prediction is significant. It is important to be ensure that all the cut-on wave modes are included otherwise the predicted results will not be very accurate. The more modes that are included, the more computer storage is required; therefore, the number of modes need to be enough to obtain accurate result but not too many to be over the limit of computer storage. The high number of modes used also decreases computer speed, increasing the running time. The mathematical model was used to predict acoustic properties. It was found that the predicted maximum acoustic pressure inside the central small region, where the disk is located, has the best correlation with the number of droplets for all liquid media and all operating conditions. The mathematical model can only predict which operating condition and atomizer design will provide the maximum acoustic pressure. As a result, we can optimize the fountain type ultrasonic atomizer in order to obtain the best result, suiting each application applied. If the geometry is changed, the model is also required to be re-written so that it will predict accurate results.

The focus of this dissertation is the development of a fundamental understanding of the acoustics and piezoelectric transducer governing the operation of piezoelectric inkjets and horn-based ultrasonic atomizers when utilizing high viscosity working fluids. This work creates coupled, electro-mechanical analytical models of the acoustic behavior of these devices by extending models from the literature which make minimal simplifications in the handling terms that account for viscous losses. Models are created for each component of the considered fluid ejectors: piezoelectric transducers, acoustic pipes, and acoustic horns. The acoustic pipe models consider the two limited cases when either the acoustic boundary layer or attenuation losses dominate the acoustic field and are adapted to account for changes in cross-sectional area present in acoustic horns. A full electro-mechanical analytical model of the fluid ejectors is formed by coupling the component models using appropriate boundary conditions. The developed electro-mechanical model is applied to understand the acoustic response of the fluid cavity alone and when combined with the transducer in horn-based ultrasonic atomizers. An understanding of the individual and combined acoustic response of the fluid cavity and piezoelectric transducer allow for an optimal geometry to be selected for the ejection of high viscosity working fluids. The maximum pressure gradient magnitude produced by the atomizer is compared to the pressure gradient threshold required for fluid ejection predicted by a hydrodynamic scaling analysis. The maximum working fluid viscosity of the standard horn-based ultrasonic atomizer and those with dual working fluid combinations, a low viscosity and a high viscosity working fluid to minimize viscous dissipation, is established to be on the order of 100mPas. The developed electro-mechanical model is also applied to understand the acoustic response of the fluid cavity and annular piezoelectric transducer in squeeze type ejectors with high viscosity working fluids. The maximum pressure gradient generated by the ejector is examined as a function of the principle geometric properties. The maximum pressure gradient magnitude produced by the ejector is again compared to the pressure gradient threshold derived from hydrodynamic scaling. The upper limit on working fluid viscosity is established as 100 mPas.

This project deals with comparing types and properties of commercial produced incubators for exotic birds. It searches the best solution from these area. In this project are compars individual components and their choice for realization in this project. Then in this project is solution of regulation temperature and humidity in engineered mechanism and discovered parameters of specifically space. Then is developed solution of thermostat and hydrosatat for this prototype. Temperature is changed by Peltier module, who is involved in correct system. Humidity is regulated by resistor humidifier. Complex system is managed by microcontroler. System communicates with PC via USB interface and Ethernet. Solution of this project is maked functional prototyp.

This report covers a project on a partially automated aeroponic and fungi growing system. The purpose is to evaluate if an enclosed space system can be automated to produce healthy crops of greens and fungi, and investigate how well the system can switch between these two growth modes. Factors that will be automated include regulation of temperature, humidity, air ventilation, and light exposure time. The research will be focused on Romaine lettuce and Golden Oyster mushroom. The methods used include research, hardware setup, software programming, chassis construction, and experiments. Relevant factors for the growing environment, such as lighting, temperature, and nutrient solutions were studied. The hardware components used in the project can shortly be described as follows. A real time clock ensure accurate timing for the microcontroller that regulates the indoor climate based on sensor readings. LEDs light up the chamber and a humidifier provide the roots access to a nutrient solution. A fan provides cooling, and filters block out unwanted microorganisms and fungi spores from the ventilation air. A display provides the user with relevant information. The system code written in C++ contain six main functions and two support functions. Depending on the growth mode, climate control functions are selected. The system has control variables allowing the administrator to set threshold levels for humidity and nutrient spray periods. The outer case of the chassis was made out of painted acrylic to block out light and retain moisture. The water-nutrient solution basin was designed to avoid leakage, net cups hold the plants in a raised bed, a base plate acts as flooring for the mushrooms, as well as a placement enforcer for the humidifier. An inner roof separates the moist growth chamber from the electronics compartment above. Two experiments were conducted in separate prototypes simultaneously for green sand mushrooms. For the mushroom experiment, a grow kit was installed after thorough cleaning. The fruiting process was monitored and photographed daily. Results showed successful mushroom growth and healthy fruiting bodies. For the greens experiment, a nutrient solution was mixed and lettuce seeds were placed in rock wool cylinders that were installed in net cups. Photographs were taken every three days to track the progress. The lettuce seeds germinated and started growing. Control variables were altered multiple times to maximize performance but optimal settings were not found. The plants died whilst unsupervised. The experiments were partially successful and demonstrated potential for growing both greens and mushrooms. The prototype was effective in maintaining set temperature and humidity levels. The parameters necessary for successful growth was effectively automated and the system has great potential for further improvements and automation. / Målet med projektet är att studera hur väl det går att odla både svamp och fotosyntetiserande växter i samma slutna, delvis automatiserande aeroponiskasystem. I projektet undersöks om det går att byta mellan de två odlingssätten och hur automatiserad processen kan vara. Produkten är tänkt att fylla utrymmet som hittats på marknaden för enkla odlingssystem hemma för i synnerhet svamp. Faktorer att ta hänsyn till är temperatur, luftfuktighet och ljusexponeringstid. Andra faktorer som pH värde eller byte av vattnet utesluts till följd av tid- och resursbegränsningar. Metoden är indelad i forskning, hårdvara, mjukvara, chassi och experiment. Forskningen täcker nödvändig information om faktorer relaterade till odling av både svamp och gröna växter i aeroponiska system. Exempelvis hur mycket ljus, vatten och näring som behövs. Kapitlet om hårdvara tar upp vilka komponenter som används och varför. I centrum är en microkontroller, en Arduino micro, som med hjälp av en realtidskolocka styr när belysningen ska lysa, när luftfuktaren ska vara på samt när fläktarna ska gå. En DHT11 sensor skickar information till Arduinon att agera utifrån. I mjukvara ingår hur koden är uppbyggd för att styra microkontrollern och hur användaren kan anpassa värden till sitt tycke. För att hjälpa användaren visas relevant data på en skärm. Produkten är uppbyggd med ett mörklagt och tätande skal av akrylplast. Vatten med eventuell näring för växtläget är samlat i en tät balja längst ner i lådan där luftfuktaren även är placerad. Över baljan vilar antingen ett svampodlingskit på en perforerad yta eller en hållare för odling av växter i nätkorgar med stenull. I taket är en 20W LED fäst på en kylfläns för kylning tillsamman med en närliggande fläkt. Allra högst upp är elektroniken, skyddad från fukten nere i lådan av ett lager akrylplast.Två experiment hölls parallellt med varandra i två likadana odlingskammare för att hinna utvärdera både svamp och fotosyntetiserande växter. Citronmussling valdes som svamp och Romansallad som växt. Experimenten dokumenterades regelbundet med fotografier och kommentarer om det som observerats. Experimenten var till stor del lyckade även om vissa parametrar behövde justeras under förloppet. Det aeroponiska systemet producerar svamp och växter av god kvalitet. Slutsatsen som kan dras är att det går att odla både svamp och växter i samma produkt. De parametrar som inkluderats inom projektets avgränsningar gick att automatisera. Det finns även goda möjligheter att förbättra automatiseringsnivån.