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Two-Phase Pressure Losses Quarterly Progress Report: Fifth Quarter, February 12, 1963 - May 12, 1963

Description: Technical report describing that void measurements were made in the 1/2-inch by 1-3/4-inch rectangular channel, for both flow up and flow down, at pressures of 600, 1000, and 1400 psia, and at various flows and quantities. Results at 1000 psia and 20 percent quality show that for the lowest flow both the void distribution and the average void are much different for flow down than for flow up, the void fraction for flow down being much higher. However, when the flow is increased both the void distribution and average void for flow down tend to approach the corresponding values for flow up. At 1000 psia, both flow up and flow down, the void fraction for 5 percent quality increases gradually from the wall to the center of the channel, and peaks at the center. At 20 percent quality, the void fraction increases abruptly from the wall and tends to be constant over the middle 65 percent of the channel. the void fraction for flow down is always greater than for flow up, other things being equal.
Date: June 1, 1963
Creator: Janssen, E. (Engineer) & Kervinen, J. A.
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Two-Phase Pressure Losses Quarterly Progress Report: Seventh Quarter, August 12, 1963 - November 11, 1963

Description: Technical report describing that the pressure drop along an annular channel with dimensions D(1) = 0.375 inch; D(2) = 0.875 inch, L = 70 inches. Flow was vertical and upward, and only the internal surface was heated. Subcooled conditions existed at the inlet, with two-phase conditions at the exit. Groups of three radial spacer pins on 18-inch centers along the channel, held the inner surface concentric with the outer surface. The single phase loss coefficient for each spacer group is K(8) = 0.21. The single phase friction factor for the annual channel is given by f = 0.16 N(R)(-0.16). The two phase pressure drop increases as the quality increases for G [over] 10(6) = 0.5 ;b/hr ft(2). The effect of heat flux on the pressure drop is very is very slight over the range of fluxes tested (0.55 less than or equal to Q over 10(6).\ less than or equal to 0.8). The two-phase pressure drop gradient in the same annulus, with no heat addition is qualitatively the same as for a 1/4-inch by 1-3/4 inches rectangular channel but is quantitatively greater than for the rectangular channel.
Date: December 2, 1963
Creator: Janssen, E. (Engineer) & Kervinen, J. A.
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Two-Phase Pressure Losses Quarterly Progress Report: Sixth Quarter, May 12, 1963 - August 12, 1963

Description: Technical report describing that the pressure drops along 3/4-inch, 1-inch, and 1-1/4 inch straight pipes and across three contraction-expansion inserts in a 1-inch pipe have been measured under both single- and two-phase flow conditions. Pressure was varied from 600 to 1400 psia, flow from 0.25 x 10(6) to 1.66 x 10(6) lb/hr ft, and quality from zero to 90 percent. The single-phase pipe friction factor agrees with the Moody value for smooth pipe. The two-phase friction for horizontal flow shows no size effect in the range of pipe sizes from 3/4 inch to 1-1/4 inch. The values lie below the Martinelli curve at the lower qualities (x<0.6), but at high qualities tend to be above the Martinelli curve. The single-phase loss coefficient for the three contraction-expansion inserts show very little Reynolds number effect in the range of channel Reynolds numbers from 3 x 10(4) to 5 x 10(5). The two-phase data for insert number 1 has not yet been reduced. The two-phase loss for insert numbers 2 and 3 lies generally below the loss prediction based on a homogeneous flow model. The two-phase loss for insert number 2 shows excellent agreement with the corresponding loss for the S-1 insert in the 1/2- by 1-3/4-inch rectangular channel reported earlier. The two-phase loss for insert number 3 agrees fairly well with the loss for the S-5 insert.
Date: September 1, 1963
Creator: Janssen, E. (Engineer) & Kervinen, J. A.
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