CHARACTERISTICS OF ADHESION OF DIESEL FUEL ON IMPINGEMENT DISK WALL. PART 1: EFFECT OF IMPINGEMENT AREA AND INCLINATION ANGLE OF DISK

Adhesion characteristics of diesel fuel spray impinging on a flat wall disk were investigated experimentally. Non-evaporated diesel spray was injected into a high-pressure vessel. A circular disk wall was set vertically or inclined to the spray axis to catch the adhered fuel. Various sizes of disk and inclined angles were tested in order to observe the behavior of impinging spray. The mass of the disk with adhered fuel was measured using an electronic balance, and the fuel mass adhered to the disk surface was evaluated. The adhered mass became constant with increasing disk diameter (D-d) from D-d = 25 mm to D-d = 50 mm. Moreover, the thickness of the liquid film tended to decrease with increase of injection pressure. As the inclination of disk became steeper from 0 deg to 50 deg, the adhered fuel mass ratio became lower. Further; to explain the general trend of adhered fuel mass, modified adhered mass ratios combined with disk diameter and inclination angle were introduced.