Çift Fazlı Sprey Akışlarının İncelenmesi

Abstract

Dünya üzerinde kürasel ısınma ve iklim değişikliği tehdidi son günlerde artarak etkisini göstermektedir. Gelişen teknoloji sayesinde günlük hayatımız kolaylaşmakta fakat dünya üzerindeki doğal hayata olan etki de giderek artmaktadır. Bu sebeple günümüz toplumları gerek sivil gerekse devletler bazında örgütler oluşturarak insanların bilinçlenmesi ve bu bilinç doğrultusunda endüstriyel gelişimin oluşmasına çalışılmaktadır. Dolayısıyla toplumsal bilinçlenme hareketine endüstriyel üreticiler de uymaktadır ve toplumun isteğine paralel olarak daha çevreci ürünler; daha az enerji tüketen, daha az su tüketen ürünler gibi, üretilmeye çalışılmaktadır. Kullanıcı tarafında ise satın alınan ürünlerin teknik özelliklerinin yanında enerji tüketim mikatarları, su tüketim miktarları ve ürünlerin çalışma sürelerine de dikkat edilmektedir. Toplumlarda, enerji verimliliği kavramının oluşması, tüketicilerin enerji konusunda bilinçlendiğinin bir göstergesidir. Ayrıca bu tasarrufu yaparken günümüzün hızlı yaşamına ayak uyduran daha hızlı ve daha kullanıcı dostu ürünlere talep git gide artmaktadır. Enerji kaynaklarının giderek azalması, insanların hızlanan yaşama ayak uydurma isteği ve sivil toplum kuruluşları, Avrupa Birliği gibi oluşumların katılımıyla düzenleme ve yönergelerin yayınlanması bu konunun önemini açıklamaktadır. Endüstriyel üreticiler, ürünlerinin teknik özelliklerinin geliştirmektedir, ürünlerinin enerji verimliliğini arttırmakta ve daha hızlı olmaları için çalışmaktadırlar. Enerji verimliliğinin artırılması başlığı altında gerçekleştirilen çalışmalar, enerji verimliliğinin etkili olduğu sistemlerde yenilikçi fikirlerin, uygulamaların ve optimizasyonların geliştirilmesi zorunluluğunu doğurmaktadır. Bu yüksek lisans tez çalışmasında kirlerin hızlıca çıkartılması amacıyla kullanılan temizleme cihazının sprey akışı shadowgraph görselleme tekniği kullanılarak incelenmiştir. Su jeti debisi, hava jeti debisi ve jetler arasındaki açı parametrelerinin, su ve hava jetinin çarpıştırılmasıyla oluşturulan sprey üzerindeki etkileri araştırılmıştır. Akış görsellemesi yapılan farklı jet sistemi tasarımlarının tekstil üzerindeki yıkama performansları incelenmiştir. Tez çalışması beş ana bölümden oluşmaktadır. Birinci bölümde çalışmaya başlama nedenleri, çalışmaların bitiminde hedeflenen sonuçlar, çalışmalarda izlenilen yöntem ve problemin kısıtları genel hatlarıyla açıklanmıştır. İkinci bölümde, söz konusu konu ile ilgili olarak gerçekleştirilen literatür araştırmaları gösterilmektedir. Yapılan literatür araştırması sonucunda daha önce yapılan çalışmaların çoğunlukla aynı fazdaki akışkanların çarpıştırılarak elde edilen spreyler hakkında olduğu görülmüştür. Oluşturulan spreye etki eden temel parametrelerin çarpıştırılan jetlerin debileri ve aralarındaki açı olması sebebiyle, su jeti debisi, hava jeti debisi ve jetler arası açı parametrelerinin sprey üzerindeki etkileri incelenmiştir. Üçüncü bölümde sprey akışlarına ait genel bilgiler verilmiştir. Bu kapsamında, sprey oluşum yapısı, atomizör türleri, sprey akışı, spreyin parçalanması ve spreylerin sınıflandırılması kullanılan istatiksel yöntemler anlatılmıştır. Dördüncü bölümde deney düzeneği, yapılan deneysel çalışmalar ve sonuçları hakkında bilgi verilmiştir. Sonuç bölümünde ise yapılan çalışmalar doğrultusunda elde edilenler yorumlanmış ve önerilerde bulunulmuştur.

Time is an important parameter in the recent developing lifestyles all over the world. In fact the speed of causal live increases day by day. Therefore, the work completion time is tried to be reduced as much as possible. In order to find a solution to this issue, new product ranges have been recently created and new technologies are implemented to home appliance products. One of the best examples for quick washer solution is surface cleaner devices in household appliance market. Especially, conventional washers due to long wash cycles and drying requirements after washed a serious problem for ease of use. Also, diffucult dirties can not be clean normal wash cycle and pre-treatment is required. Surface cleaner devices uses spray that occured by impinging water and air jets for washing textiles. Pressurized air and water jets impinged each other out from their orifices. Air jet is presurized by using compressor and same as; water jet is pressurized by using pump. Air jet is assisted occuring mist sprey because, water jet pressure is not enough alone. Chemicals and detergent solutions are mixed water and so, combined chemical and physical effects are applied to the desired surface. Thus, the daily dirties are rapidly cleaned. The aim of this thesis is to experimently investigate the spray structure used in the cleaning device, examine the parameters affecting the spray structure and evaluate cleaning performance of the designed jet structures. This M. Sc. study begins with literature search. By the end of this M.Sc. study, it is planned to find new spray structure, which is alternative to used surface cleaner device spray. Literature related to sprays and spray structure are search. Afterwards, the test assembly and test methods are designed to investigate the spray construction. In the light of this design, it is requested to examine the effect of the studied parameters. Within the scope of studies, eight different tests are planned using DoE (Design of Experiments) MiniTab module. Thereafter, the experimental data are analysed by MiniTab programme. This phase is followed by examining the position and distribution of the water drops in the sprey. And then washing performances of designed jet systems are analyzed. In the final chapter of the study, the optimum parameters and best jet system are determined by introducing advantages and disadvantages. In this study, for investigate spray construction of the surface cleaner device, the effects of the water jet volumetric flow rate, air jet volumetric flow rate and the angle between jets were studied experimently with using shadowgraph visulation technique. And then, the effect of the wash performance of the water jet volumetric flow rate, air jet volumetric flow rate and the angle between jets was investigated. This thesis study is composed of five main chapters. In chapter one, motivation and aim of this study were explained in general terms as an introduction. xxiv In the second chapter, literature research about thesis was outlined. As a result of this research were presented. After the literature research, it was noticed that, the research are generally represents sprays, sprays construction, impinged jets, and twin jet flows. The categorization composed of sprey atomizers appliances with pressure nozzles, air assisted nozzles and swirl flow nozzles appliances. In my study, occurred spray is same as air assisted nozzle spray flow, but this spray construction different from impinged jet spray flow, because of atomization type. Therefore, the literature research outlines non-twin jet impinged flow. In the third chapter, spray construction, and spray properties is outlined. Atomization types and jet breakup models such as drops, Rayleigh, sinusoidal, large frequency and atomization types were presented. Spray classification methods were represented with using statistical analysis. In the fourth chapter, the design of experimental setup used in the study is described with details. Furthermore, camera, light source and equipments were used in this setup are explained. Second section of fourth chapter experiments were done within this thesis were described effect of spray parameters were showed and explained. Firstly we examined three parameter effects on the spray construction. These are water jet volumetric flow rate, air jet volumetric flow rate and then angle between jets. After spray analysis, we get water drop mean diameter values such as arithmetic mean diameter, drops area mean diameter and Sauter mean diameter, and spray angle values. Regression analysises were done for these with using MiniTab program. In chapter five analytical studies were explained. Analytical studies about the system and the methods were used for this analytical studies were detailed in the fifth chapter. Spray constructions examined respect to drops distribution, drop diameters and drop intensity. Furthermore, wash performances of the different designed jet systems were analyzed. At the end of the chapter experimental results were evaluated with statistical method. Statistical analysis was done with MiniTab software. This software showed main effect graphics and total effect pie chart about the experimental results. In the final chapter results of this study have been evaluated and suggestions have proposed. In this study, for increasing the wash performance of surface cleaner devices, the effects of the water jet volumetric flow rate, air jet volumetric flow rate and the angle between jets were investigated. The results achieved within this thesis can be summarized as follows: Water jet volumetric flow rate is the most influential parameters in the spray droplet diameter size. Another important parameter is the angle between the jets. Because the system operating points from experiments study the effects of air jet flow it could be seen. Effect on spray angle was found to be the angle between the highest parameters of the jets. Where the angle between the jets 60 ° more intense spray was obtained according to other test results. Formed by the investigated jet systems intended pretreatment device with detergent in washing efficiency performance made by the chemical effect was found to be the most important parameter. In tests detergent it has been the impact of the application of the highest magnitude. xxv Application area of the field is more than 4 cm2 were scanned per unit time while suppressing the influence of other parameters. After the application areas most influential parameter is the diameter of the water jet. Will achieve higher speed jets at low water jet diameter value was obtained even better wash performance. The spray performance tests created in the formation of small drops of water or no effect is estimated to be generated by more intense. In this case the textile washing performance, due to higher mechanical impact creating discloses give better performance of high-speed jets. Wash performance of these focuser jets is better. Created friction effect of the pre-treatment device applied to a textile has been seen to prevent the spray performance. Increasing the wash performance test, the more significant differences between spray performances are expected to cause.