Gas Power and Jet Propulsion Analysis - Analyze Gas Turbines and Jet Engines - Manual for the Web-Based Gas Power Software

Tutorial (TOC) > Daemons > Gas Power Cycles > Manual

a. Open Power Cycles: Open Cycle daemons can be used both for: (i) Vapor Power Cycles and (ii) Gas Power Cycles depending on the choice of working fluid. The characteristics of an Open-Device cycle is the back-to-back arrangement of several open-steady devices that form a closed loop. If only the overall cycle quantities are of interest, a much simpler daemon, Closed-Steady daemon, can be used instead.

The building block of the open-cycle daemon is the open steady daemon (discussed in the Tutorial>Daemons> OpenSteady>Manual page), which should be explored first for effective use of the open-cycle daemon.

Fig. 1 Image of Device Panel. Only a single inlet and exit are used in the device.

b. Device Panel: The device panel in an open-cycle daemon is slightly different from those found in an open-steady daemon. As shown in Figs.1 the device panel combines multi-flow-mixed and multi-flow-unmixed devices on a single panel. By using the radio buttons any specific device can be turned into a mixing (open feed water heater, turbine with bleeding) or non-mixing (closed feed water heater or a heat exchanger), making it possible to analyze complicated cycles.

Although the device allows for two inlets and two exits, by leaving a port at its Null-State, it can be converted into a single-flow, mixing, separating, or non-mixing device.

Fig. 2 Image of Cycle Panel for the power cycle.

c. Cycle Panel: The cycle panel displays all the cycle related variables which are extracted from the device panel after all of the devices forming a loop have been calculated.

d. Parametric Studies: Once an Open Cycle has been set up, it is relatively simple to evaluate the effect of changing one or more variables on the problem. Simply change the independent variable, say the turbine efficiency, to a new value, Calculate and Super-Calculate. The state, device and cycle variables are all updated to the new parameters.