EFFECT OF GEOMETRIC CHARACHTARISTICS ON THE AERIATION EFFFICINCY IN THE VENTURI SYSTEM

Abstract

Sufficient dissolved oxygen is required for helpful water quality. Natural stream cleansing procedures need enough oxygen levels for the purpose of supply for aerobic life systems. The happening of oxygen and water mixing together is titled aeration. There are several techniques to add air or oxygen to water, for instance open air reservoirs, submergible pumps, domestic aeration systems, compressor systems and air pump systems. However, the Venturi system, relied on the easiness of Ejectors, gives a easy, preservation free aeration solution. venturi system permits air to be injected inside running water from air inlet orifices and so rises oxygen levels in the water. The main objective of this research is to evaluate effect of geometric characteristics on the aeration efficiency in the venturi system. To achieve this goal, the venturi is designed and carried out, from transparent polycarbonate. Experiments were conducted under clear-water conditions at different discharges (Qwater): 44.16, 58.88, 73.59 and 88.31 lit/min which correspond to four inlet velocities (v): 1.5, 2.0, 2.5 and 3.0 m/s. The study involved selecting three different throat lengths (Lt): 12, 24 and 36 mm, and three different air inlets orifices diameters (ds): 3, 5 and 8 mm. Five different outlets angles have been used (β): 7 o , 10 o , 15 o , 21 o , and 25 o with inlet angle (α) stabilization at 7 o. The inlet and the outlet diameter (D) and throat diameter (dt) in all the experiments were constants and equals to 25 and 10 mm, respectively. The results of the study demonstrated that the geometric characteristics of the venturi system affects the aeration efficiency. Additionally, empirical equations were gotten for venturi tubes linking air flow and water flow to throat lengths and diameters, venturi outlets angles, air inlets orifices diameters and Reynolds numbers. ‫في‬ ‫التهوية‬ ‫كفاتة‬ ‫على‬ ‫الهندسية‬ ‫ظر‬ ‫تحت‬ ‫التجارب‬ ‫أجريت‬ (‫مختلفة‬ ‫تصريفات‬ ‫عند‬ ‫نقية‬ ‫مياه‬ ‫وف‬ water Q :‫هى‬) 44.16 , 58.88 , 73.59 ‫و‬ 88.31 ‫دقيقة‬ / ‫لتر‬ (‫ردخل‬ ‫مر‬ ‫ررعات‬ ‫سر‬ ،‫ر‬ ‫أربر‬ ،‫م‬ ‫تتوافق‬ ‫والتي‬ v :‫رى‬ ‫هر‬) 1.5 , 2.0 , 2.5 ‫و‬ 3.0 ‫روال‬ ‫أطر‬ ‫رة‬ ‫ر‬ ‫ال‬ ‫رار‬ ‫اختير‬ ‫رى‬ ‫علر‬ ‫رة‬ ‫الدراسر‬ ‫رتملت‬ ‫اشر‬ .‫ث‬ / (‫المختنق‬ ‫للقطاع‬ ‫مختلفة‬ t L :‫هى‬) 12 , 24 ‫و‬ 36 ‫مختلف‬ ‫أقطار‬ ‫ة‬ ‫ال‬ ‫و‬ ، ‫مم‬ (‫الهوات‬ ‫دخول‬ ‫لفتحات‬ ‫ة‬ s d :‫رى‬ ‫هر‬) 3 , 5 ‫و‬ 8 ‫رم‬ ‫وتر‬ .‫رم‬ ‫مر‬ (‫للمخارج‬ ‫مختلفة‬ ‫زوايا‬ ‫خمس‬ ‫استخدا‬ β : ‫رى‬ ‫هر‬) 7 ، 10 ، 15 ، 21 ‫و‬ 25 (‫ردخل‬ ‫المر‬ ‫رة‬ ‫زاوير‬ ‫رت‬ ‫تثبير‬ ،‫ر‬ ‫مر‬ ‫رة‬ ‫درجر‬ α ‫رد‬ ‫عنر‬) 7 .‫رة‬ ‫درجر‬ (‫والمخرج‬ ‫المدخل‬ ‫قطر‬ ‫وكان‬ D (‫المختنق‬ ‫القطاع‬ ‫وقطر‬) t d ‫راو‬ ‫ويسر‬ ‫وابت‬ ‫التجارب‬ ،‫جمي‬ ‫في‬) 25 ‫و‬ 10 ‫روالي‬ ‫التر‬ ‫رى‬ ‫علر‬ ‫رم‬ ‫ملر‬. ‫رول‬ ‫الحصر‬ ‫رم‬ ‫تر‬ ، ‫رن‬ ‫ذلر‬ ‫رى‬ ‫إلر‬ ‫باإلضافة‬ .‫التهوية‬ ‫كفاتة‬ ‫على‬ ‫ر‬ ‫تؤ‬ ‫الفنيور‬ ‫لنظا‬ ‫الهندسية‬ ‫الخصائ‬ ‫أن‬ ‫الدراسة‬ ‫نتائج‬ ‫أظهرت‬ ‫وقد‬ ‫رارج‬ ‫مخر‬ ‫را‬ ‫وزواير‬ ‫رق‬ ‫المختنر‬ ‫راع‬ ‫القطر‬ ‫رار‬ ‫وأقطر‬ ‫بأطوال‬ ‫المياه‬ ‫وتدفق‬ ‫الهوات‬ ‫تدفق‬ ‫تربط‬ ‫التي‬ ‫الفنيور‬ ‫ألنابيب‬ ‫تجريبية‬ ‫معادالت‬ ‫على‬ ‫ا‬ ‫دخول‬ ‫فتحات‬ ‫وأقطار‬ ‫الفنيورى‬ .‫رينولدز‬ ‫وأرقا‬ ‫لهوات‬ .‫المياه‬ ‫جودة‬ ,‫الفنشورى‬ ,‫الهواء‬ ‫حقن‬ ,‫التهوية‬ ,‫الهندسية‬ ‫الخصائص‬ : ‫المفتاحية‬ ‫الكلمات‬