Vol. 7 No. 2 (1973)

No Abstract.

. A simple potential flow model is presented to calculate the oscillating lift on a circular cylinder. In essence, the time dependent lift acting on a cylinder is due to the presence of a vortex shed off the separation point on the cylinder. The vortex strength and its trajectory is predicted employing the condition of zero force on the vortex and its feeding vortex sheet. The vortex breaks away from the cylinder and is convected by the fluid after the vortex strength reaches a maximum value, and another vortex is shed at the other side of the cylinder. Oscillating lift with the right order…

. An objective prism survey of the Palomar-Groningen Variable-Stars Field no. 3 has been undertaken in order to determine the stellar space distribution of dB and gK stars. A concentration of dB stars has been found at the distances between 150 to 250 pcs. The color excess in this direction is found to remain very low. It only reaches 0m12 at r = 0.5 kpc and remains constant thereafter. Ringkasan. Suatu survey dengan prisma obyektip pada arah Palomar-Groningen Variable-Stars Field no. 3 telah diadakan guna menentukan distribusi ruang bintang-bintang dB dan gK. Sebuah konsentrasi…