EXPERIMENTAL STUDY OF THE CONDITIONS OF SPRAYING LIQUIDS WITH THE AIR FLOW

2021 ◽  
pp. 32-37
Author(s):  
NATALYA G. KOZHEVNIKOVA ◽  

The processes of air movement in various types of air ducts are of great practical interest in terms of designing, manufacturing, and installing spraying devices used in agricultural production to create artificial fog with fi ne sprinkling and treat crops from pests and diseases. The authors analyze the existing methods of liquid spraying and reveal their main advantages and disadvantages. Under special attention is the pneumatic method. The study found that this method is used to spray contaminated liquids and the spray quality insignificantly depends on the liquid flow rate. It was revealed that one of the main factors affecting the quality indicators of spraying devices is the dynamic pressure of the gas medium acting on the liquid during its spraying. The research has determined that the dynamic pressure value of the airflow during the liquid movement in a horizontal duct depends on three factors: the presence of additional resistance, estimated by the value of the effective area duct, the position of the point at which the pressure was measured relative to the duct axis and the distance between the measurement point and the airflow source. The experimental data were tested for reproducibility using the Cochran criterion at the 5% signifi cancelevel, which proved the process reproducibility. The research has shown that the presence of additional resistance in the duct and the position of the dynamic pressure measurement point relative to the axis of the duct have the same effect on its value. The dynamic pressure of the airflow is primarily dependent on the remoteness of the measurement point from its source.

2017 ◽  
Vol 6 (7) ◽  
pp. 5426 ◽  
Author(s):  
Hiren J. Patel ◽  
Vaishnavi P. Parikh

The pharmaceutical industry has faced several marked challenges in order to bring new chemical entities (NCEs) into the market over the past few decades. Various novel drug delivery approaches have been used as a part of life cycle management from which Osmotic drug delivery systems look the most promising one. After discussing the history of osmotic pump development, this article looks at the principles, advantages and disadvantages of osmotic drug delivery systems. Then, the basic components of osmotic pump and factors affecting the design of oral osmotic drug delivery systems are discussed in detail. In the later part of the manuscript, various types of osmotic pumps available in the market and evaluation methods for osmotic drug delivery systems are discussed in detail.


Author(s):  
Nikhil Ashokbhai Baraiya ◽  
Baladandayuthapani Nagarajan ◽  
Satynarayanan R. Chakravarthy

In the present work, the proportion of carbon monoxide to hydrogen is widely varied to simulate different compositions of synthesis gas and the potential of the fuel mixture to excite combustion oscillations in a laboratory-scale turbulent bluff body combustor is investigated. The effect of parameters such as the bluff body location and equivalence ratio on the self-excited acoustic oscillations of the combustor is studied. The flame oscillations are mapped by means of simultaneous high-speed CH* and OH* chemiluminescence imaging along with dynamic pressure measurement. Mode shifts are observed as the bluff body location or the air flow Reynolds number/overall equivalence ratio are varied for different fuel compositions. It is observed that the fuel mixtures that are hydrogen-rich excite high amplitude pressure oscillations as compared to other fuel composition cases. Higher H2 content in the mixture is also capable of exciting significantly higher natural acoustic modes of the combustor so long as CO is present, but not without the latter. The interchangeability factor Wobbe Index is not entirely sufficient to understand the unsteady flame response to the chemical composition.


2017 ◽  
Vol 2 (3) ◽  
pp. 142-155
Author(s):  
Auzan Syahmi ◽  
Irwan Irwan ◽  
Romano Romano

Abstrak . Lada merupakan salah satu  tanaman rempah-rempah yang berasal dari tanaman perkebunan yang sangat terkenal dahulu di Aceh. Khususnya Petani lada di Aceh saat ini sudah mulai memperhatikan lada untuk dikembangkan dengan tujuan meningkatkan pendapatan dan kesejahteraan. Dengan kata lain, Lada menjadi komoditi primadona yang banyak diminati di perdagangan dunia. Karena berbagai negara menggunakan lada ini sebagai bumbu dapur masakan. Disisi lain disebabkan berkembangnya usaha makanan, berkembangnya industri farmasi, kosmetika yang menggunakan lada sebagai salah satu bahan baku, meningkatnya konsumsi dunia, konsumsi dalam negeri semakin meningkat dengan bertambahnya produk-produk industri makanan berbasis lada. Akibat permintaan lada yang tinggi menyebabkan terjadinya masalah bagi petani Aceh dalam keterbatasan produksi lada. Salah satunya lahan pertanian dikonversikan menjadi non pertanian seperti perumahan, gedung dan pertokoan. Sehingga lahan pertanian menjadi berkurang dan menjadi masalah bagi petani lada sendiri dalam mengembangkan lada. Penyebab masalah lain juga yang akibat hama dan penyakit terutama penyakit layu, penyakit keriting daun serta penyakit busuk pangkal batang. Tujuan Penelitian untuk mengetahui faktor-faktor yang diperhatikan pada pengembangan lada, serta mengetahui strategi pengembangan lada yang tepat. Metode Penelitian yang digunakan adalah metode studi kasus. Teknik Pengumpulan data digunakan dengan pendekatan wawancara. Hasil analisis  menunjukkan faktor internal yang  mempengaruhi usaha pengembangan lada adalah bibit, pestisida, sumber daya alam, pupuk, dan sumber daya manusia. Sedangkan faktor eksternal yang mempengaruhinya adalah pemerintah, pasar, harga, pesaing, hama dan penyakit. Berdasarkan hasil analisis SWOT didapatkan nilai IFAS (Internal Strategic Factors Analysis Summary)  sebesar 1,756 dan EFAS (Eksternal Strategic Factors Analysis Summary)  sebesar 2,773 berada pada kuadran I , maka  strategi pengembangan yang cocok untuk strategi pengembangan lada adalah  strategi agresif  yang artinya usaha tersebut sangat dimungkinkan untuk terus berkembang, meningkatkan pertumbuhan dan meraih kemajuan secara maksimal, dimana strategi agresif ini merupakan kondisi yang sangat menguntungkan, peluang dan kekuatan begitu besar sehingga pelaku usaha bisa memanfaatkan peluang dan kekuatan yang ada secara maksimal.Strategy of pepper development (case study of indatu farmer group in blang panyang village sub-district estuary one, Lhokseumawe City) Abstract. Pepper is one of the most popular herbs from Aceh plantations. Especially pepper farmers in Aceh are now starting to pay attention to pepper to be developed with the aim of increasing income and welfare. In other words, Pepper became the most popular commodity in the world trade. Because various countries use this pepper as a spice cooking kitchen. On the other hand, due to the development of food business, the development of pharmaceutical industry, cosmetics using pepper as one of the raw materials, the increasing of world consumption, domestic consumption is increasing with the increase of pepper based food industry products. As a result of high pepper demand causes problems for Acehnese farmers in the limitations of pepper production. One of them agricultural land converted into non-agricultural such as housing, buildings and shops. So that agricultural land becomes reduced and become a problem for pepper farmers themselves in developing pepper. Other causes of problems are also caused by pests and diseases, especially wilt disease, leaf curling disease and stem rot disease. Research Objectives to determine the factors that are considered in the development of pepper, as well as to know the appropriate pepper development strategy. The research method used is case study method. Technique Data collection is used with interview approach. The results of the analysis show that the internal factors affecting pepper development are seeds, pesticide, natural resources, fertilizer and human resources. While on external factors that include government, markets,prices, competitors,pest and diseases. Based on the result of SWOT analysis, the value of IFAS (Internal Strategic Factors Analysis Summary) of 1.756 and EFAS (External Strategic Factors Analysis Summary) of 2.773 are in quadrant I, then a suitable development strategy for pepper development strategy is aggressive strategy which means the business is very possible To continue to grow, to increase growth and to achieve maximum progress, where aggressive strategy is a very favorable condition, opportunities and strength so large that business actors can take advantage of opportunities and strengths that exist maximally.


2004 ◽  
Vol 14 (03) ◽  
pp. 393-415 ◽  
Author(s):  
CHRISTOPHE BESSE ◽  
PIERRE DEGOND ◽  
FABRICE DELUZET ◽  
JEAN CLAUDEL ◽  
GÉRARD GALLICE ◽  
...  

This paper deals with the modeling of the ionospheric plasma. Starting from the two-fluid Euler–Maxwell equations, we present two hierarchies of models. The MHD hierarchy deals with large plasma density situations while the dynamo hierarchy is adapted to lower density situations. Most of the models encompassed by the dynamo hierarchy are classical ones, but we shall give a unified presentation of them which brings a new insight into their interrelations. By contrast, the MHD hierarchy involves a new (at least to the authors) model, the massless-MHD model. This is a diffusion system for the density and magnetic field which could be of great practical interest. Both hierarchies terminate with the "classical" Striation model, which we shall investigate in detail.


2015 ◽  
Vol 72 (8) ◽  
pp. 2890-2901 ◽  
Author(s):  
David M. Romps ◽  
Alexander B. Charn

Abstract The vertical velocities of convective clouds are of great practical interest because of their influence on many phenomena, including severe weather and stratospheric moistening. However, the magnitudes of forces giving rise to these vertical velocities are poorly understood, and the dominant balance is in dispute. Here, an algorithm is used to extract thousands of cloud thermals from a large-eddy simulation of deep and tropical maritime convection. Using a streamfunction to define natural boundaries for these thermals, the dominant balance in the vertical momentum equation is revealed. Cloud thermals rise with a nearly constant speed determined by their buoyancy and the standard drag law with a drag coefficient of 0.6. Contrary to suggestions that cloud thermals might be slippery, with a dominant balance between buoyancy and acceleration, cloud thermals are found here to be sticky, with a dominant balance between buoyancy and drag.


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