A.1 HELP AND CONTROL PANELS

a. Help Panels: Distributed Help and Examples

  1. There are many places you will find helpful tips, instructions, and solved examples.
  2. At the top level, the container of this TESTapp, you will find a Hands-on Examples tab, where you can watch youtube videos on this TESTapp in action. You will also find a Discussion tab where you can post a question and get a quick answer.
  3. This particular document contains succinct instructions that are organized according to various GUI features that are common among all TESTapps, app specific help, and the material model the app uses.
  4. There are two panels, one thin row at the very top and one expandible row at the very bottom, where dynamic help messages are displayed.
  5. As you move mouse over a variable or button, helpful messages are displayed at the bottom panel. While the definition of the variable appears on the bottom panel, precise value of a variable is displayed at the top.
  6. As the solution progresses, helpful messages of different categories (Tip, Warning, and Error) are displayed at the bottom. Some messages stick around longer than others based on their severity.

b. Control Panels

  1. The first row of buttons below the top help row is the super-contrrol Panel. You probably will use this panel either at the start or the end of a solution.
  2. The overall unit system is SI units by default. Even if you select the English system, any user defined variable is interpreted in SI Unit. So if you define a variable 'pInlet = 200;' in the I/O Panel and use '=pInlet' for p1, a value of 200 kPa will be used for p1.
  3. To convert the entire solution to English system, select English, and click the Super-Cal button.
  4. For apps that offer exergy analysis, you must check the Include Exergy checkbox for exergy variables to be displayed in different panels. By default exergy variables are not displayed to avoid clutter.
  5. At the end of a solution, you can perform a parametric study and generate a detailed report by clicking the Super-Cal button. When you change a property, you must Calculate the state firt before the Super-Cal button can update all computations. Not only all the states are updated, but so are the User-Codes in the I/O Panel, if any. A detailed output of the solution is also posted on the Output Area of the I/O Panel.
  6. All other panels are organized in tabs below the super-control panel. Each of these panels has its own control panel. They are discussed in separate sections below. While most of the features in various tabs are obvious, the I/O Panel has some powerful features that you may miss unless you read the I/O Panel section below.

A.2 TAB PANELS

a. State Panel: Calculating states

  1. Select a working substance.
  2. Select a state number either from the drop-down list (0-100) or by using the left and right buttons next to the state menu. Note that State-0 is reserved for dead state which is evaluated at the temperature and pressure of the surroundings. All other states use State-0 for calculating phi and psi.
  3. Input known variables by clicking on the checkbox or value field, entering a value or expression, and selecting a desirable unit.
  4. If the value you are trying to enter is a dependent variable, a red error message is displayed on the help panel (at the bottom). Note that the symbols are color coded according to their classification and hovering the mouse over the symbol displays a short description in the bottom help panel.
  5. Click Calculate (or press the Enter key) to evaluate as many properties based on your input.
  6. You can use relational expression (=p1, =h1 + 0.9 (h2-h1)/(h3-h1), etc) in the value field
  7. You can change unit of any calculated variable or the entire state by selecting a unit system (from the top panel).
  8. After changing the unit system, you can click the Super-Cal button to update units of all calculated states.
  9. To use Mixed unit system, you must select your preferred units in State-1 first, which are then propagated to other states.
  10. You can explore the relationship among state properties by clicking on properties. TESTapp checks for dependencies before entering into input mode.
  11. If there are two solutions (say A and Astar are known), the subsonic solution is displayed with the supersonic Mach number displayed on the help panel at the bottom. To obtain the supersonic solution make A or Astart unknown and use the alternartive Mach number.

b. Gas Dynamics Tables: Dynamically generate the gas dynamics tables

  1. The gas selected in the State Panel is the gas for which tables are constructed in this panel.
  2. Isentropic Table: Supply one of M, p/p_t, T/T_t, or A/A* to obtain the remaining variables. Note that for a given A/A* there are two solutions: select either the supersonic or the subsonic branch that is appropriate.
  3. Normal Shock Table: Subscript i and e refer to before and after the shock. Supply one of the Mach numbers or the property ratio to obtain the rest of the variables.
  4. Delta-Theta (Oblique Shock) Table: Subscript i refers to the upstream flow and e to the flow after the oblique shock. Given a supersonic upstream Mach number and the shock angle theta, the turning angle and the downstream Mach number are calculated. If delta is known, there mayb two solutions for theta. Park the pointer over theta to see the alternative solutoin (strock shock solution) on the message panel
  5. Prandtl-Meyer Expansion Fan Table: Given a supersonic upstream Mach number, it calculates the wave angel μ and the turning angle ν from a reference set at Mach = 1.
  6. Oblique-shock and expansion fan are advanced topics of gas dynamics covered in gradualte level classes.
  7. You can use state properties or custom variables declared in the I/O Panel in the table panel.

c. Graphics Panel: Visualizing calculated states in thermodynaic plots

  1. Calculated states are displayed in various thermodynamic diagrams. It allows you to visually check if the calculated states make sense.
  2. A table of calculated properties is also displayed next to the graphics box.
  3. After you calculate a state, the Graphics Panel is automatically updated.
  4. The T-s diagram is displayed by default. You can select other diagrams from the drop-down menu. More features will be added to this panel in the future.

d. The Device Panel:

  1. In the device panel, you can analyze an open-steady device, such as a nozzle, graphically as an alternative to writing code in the I/O Panel.
  2. States which are set up (either totally or partially calculated) in the States Panel, appears in the inlet and exit ports of the device image.
  3. Set up the inlet and exit states and then enter the values of the known device variable (Qdot=0, for example, for an adiabatic turbine).
  4. When you click Calculate, mass, energy, and entropy equations are solved for this particular device. If the result produces a state property (say, j2 or s2), it is posted back with a blue background in the corresponding state.
  5. If the states are completely known, then the unknown device variables are calculated and displayed.
  6. You can go back to the inlet and exit states in the State Panel and Calculate those states if a device analysis produces unknown state properties.
  7. To automate this process, simply click the Super-Cal button to iterate between the State and Device panels.
  8. It is always a good idea to use an extra Calculate in the device panel to make sure that mass, energy, and entropy equations are satisfied by your analysis (see the Help panel at the bottom where messages appear).
  9. The device variables such as Qdot1 or SdotGen1 can be used in the I/O panel just like state properties (p1, T1, etc.).
  10. Just as you can calculate multiple states, you can analyze multiple devices the same way.
  11. A Super-Cal also produces a detailed output and, more imporantly, the TEST-codes (in the I/O Panel), which can be used later to regenerate the solution. All you do is paste the codes back into the Input Area of the /O Panel and click the Load button.

e. I/O Panel: You can do several things in the I/O panel

  1. Use the Input Area as a scientific calculator: Begin an expression with the equal (= sign) and click Calculate or press the Enter key. Examples: =sin(pi/2); = log (exp(2)); etc. Results are displayed in the Output Area.
  2. Use the Input Area as a programming area: You can write simple code in a typical programming language syntax and click Calculate or press the Enter key. Comment lines begin with the '#' character.

    3. Example:

    # find the hypotenuse and the smallest angle in a right angled triangle
    x = 3;
    y = 4;
    z = sqrt (x^2 + y^2);
    theta = (180/pi)*atan(y/x);
    # This will display values of x, y, and z on the Output Area when you click Calculate or press the Enter key.
    # Note that variables such as p1, T2, x5, h10, etc., will be interpreted as state properties and, hence,
    # cannot be used as a user defined variables. Multiple statement can be typed in in a single line separated by
    # semi-colon(;)
    p/><
  3. You can use evaluated variables such as pressure, temperature, etc in the code.

    4. Example:

    # Energy and entropy analysis of a turbine operating at steady state.
    # It is assumed that States 1 (inlet), 2 (isentropic exit), 3 (actual exit) states are already calculated.
    WdotT_s = mdot1*(h1-h2);
    WdotT_a = mdot1*(h1-h3);
    turbEff = 100* WdotT_a/Wdot_a;
    Sdotgen = mdot1*(s3-s1);
    # Even though the Device Panel (as in the Java based TESTcalcs) is not yet available, this example shows that a device analysis is quite
    # possible in the I/O panel.

  4. Just like the Input Area picks up calculated thermodynamic variables, user defined variables in the IO panel can be used in the State Panel.

    5. Example:

    # In the Input Area, we specify a pressure ratio and use it in a state calculation
    pRatio = 10;
    # Now, in State-2 for p2, we can enter = p1*pressureRatio; (assuming p1 is known).

  5. When you calculate the Super-Cal button, a detailed output is posted in the Output Area and TEST-code, a few lines of code describing the input. You can copy and save the TEST-code in a local text file for future use.

    6. Example of TEST-code:

    States {
    State-1: H2O
    Given: {p1 = 1000.0 kPa; T1 = 500.00 deg-C; Vel1 = 0.0000 m/s; z1 = 0.0000 m; m1 = 2.0000 kg; }
    State-2: H2O
    {T2 = 50.000 deg-C; s2 = "=s1" kJ/kg.K; Vel2 = 0.0000 m/s; z2 = 0.0000 m; m2 = "=m1" kg; }
    };
    # A detailed solution report is also displayed in the I/O Panel. Also, calculated properties of all states are displayed in a table in the Graphics Panel.
    # You can copy and save the TEST-code in your computer for regenerating the solution later as described below.
  6. To regenerate a solution, copy the TEST-code back to the Input Area and click the Load button. All the input variables in the TEST-code are read and placed in appropriate states, saving you the work of manually inputting each known variables. At present you have to calculate each affected states individually to completely regenerate the solution.