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Experimental flow rate data are presented for saturated liquid, saturated vapor, and two-phase liquid-vapor carbon dioxide through a convergent nozzle and a square-edged orifice. The data cover the range from the triple-point pressure to the critical pressure. Charts have been prepared for this complete range at critical flow. Results are also presented for subcritical flow.The tests at various back pressures indicate that the saturated liquid behaved as a cold liquid without evaporation ahead of the throat.Saturated vapor became supersaturated in the nozzle, and the vapor behaved as if no condensation occurred.Equations are presented for the flow rates of saturated vapor, and two-phase mixtures in the critical flow region.A Mollier (pressure-enthalpy) diagram is used to determine the flow rates of saturated vapor and two-phase mixtures where supersaturation takes place. In these cases, the lines of constant specific volume or density are extrapolated from the superheated region into the normal two-phase region to obtain values corrected for supersaturation.flows through a pipeline, the drop in pressure, caused by.the flow friction loss, is accompanied by a drop in temperature, and the boiling or evaporation of the liquid to convert a fraction of it to vapor in order to maintain thermodynamic equilibrium. If the liquid is colder than the pipeline, the heat transferred to the liquid also causes the evaporation of part of the liquid. This formation of vapor results in a two-phase mixture of liquid and vapor. Such a flow of a two-phase mixture of liquid and vapor occurs when liquid carbon dioxide is used for fire extinguishing purposes or for industrial work such as cooling cold chambers or material which is being processed. HISTORICALThe flow of saturated liquid and satuCritical flow nozzles or orifices are used atmosphere. This investigation was rated vapor carbon dioxide through nozzles at a back pressure of 142 lb./ sq. in. abs. was recently investigated (10).in many cases to discharge two-phase carbon dioxide from piping systems to the undertaken in order to predict the effect of nozzle or orifice design and operating conditions on the f l o~ rate. The flow rates were determined by e v a p rating and metering, at low pressure, the carbon dioxide which \vaa discharged by the nozzle or orifice. The metering was done by orifice plates which werc calibrrttcd by weighing carbon dioxide.For water at room temperature the discharge coefficient of the nozzle was 1.00. BASIC EQUATIONSThe following are the basic equations used to compute the flow rates through an ideal nozzle for negligible appro:wli velocity C1 (22). For criticd flow, P2 = P,, U? = L7r, and V2 = VI. For subcritical flow, I', = Pa. SATURATED VAPORPrevious investigators have found that saturated stcam can flow through a nozzle or orificc in a supersaturated condition (4, 18, %).In this investigation it was found that saturated carbon dioxide vapor can flow through a nozzle or orifice in a supersaturrttetl condition. Khcn floiving in R supersaturated condit...

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The self‐discharge rate of a concentration cell is considered to be due to the dissolution and ionization of alkali metal atoms in the fused‐salt electrolyte. Assuming that an equilibrium exists between dissolved alkali metal atoms and alkali metal ions and electrons, an expression was derived which relates the self‐discharge rate as a function of current. This expression was used to construct graphs showing the effect of cell current on the self‐discharge rate for a variety of conditions. It is demonstrated that the open‐circuit potential of such a cell will be less than that predicted from theoretical thermodynamic considerations.

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