Work loss in double-inlet pulse tube refrigerators

An analytic equation of the mass flow rate through the bypass of double-inlet pulse tube refrigerators was obtained by an analysis of the pressure drop in the regenerator. The work loss through the bypass is discussed based on this equation. The work toss decreases with the increase of the void volume ratio of the regenerator over the pulse tube, decreases with the increases in temperature ratio of the room temperature over the refrigeration temperature, and increases with the increase in 'double-inlet factor' which is introduced in this paper. The work loss ratio at 80K with an ideal double-inlet is about 50, 30, 20 and 10% when the void volume ratio of the regenerator over the pulse tube is 0.5, 1.0, 2.0, and 4.0, respectively. The analytic results were compared with numerical results. A good agreement between them was achieved. (C) 1998 Published by Elsevier Science Ltd. Ail rights reserved.