Welcome to SteamPlot, a graphical user interface for thermodynamic properties of fluids!
This is the main view of the application. The SteamPlot logo is in the top left corner, while the color scheme and fullscreen toggles are in the top right corner. Most of the view is occupied by the main layout area, which is used to display and organize various modules.
Let's open our first module. This dialog lists all available modules. We will go through each of them, but let's begin by opening an H-S chart.
The module is now visible. Its main area hosts a chart and its axes, with the Y-axis representing enthalpy and the X-axis representing entropy. The chart has gray gridlines and colored contours, with each color representing a specific thermodynamic property.
In the lower-left corner of the module, there is additional info about the chart. Firstly, thermodynamic properties of the axes are displayed. The first letter represents an axis, and the second letter represents a thermodynamic property. Units are displayed in parentheses. For example, the X-axis of this chart represents entropy, denoted by the letter S, in kJ/kg∙K. The Y-axis represents enthalpy, denoted by the letter H, in kJ/kg.
Furthermore, information about the current cursor position is also displayed. The first letter marks a thermodynamic property, while a number represents a value. For example, the cursor is now at an entropy of 8 kJ/kg∙K and a temperature of 1500 K.
The chart can be navigated by zooming and panning. Scroll the mouse wheel to zoom in or out. Hold and drag the primary mouse button to pan the chart. On touch-enabled devices, use pinch gesture to zoom in or out. Pan the chart by swiping with two fingers Swiping one finger over the chart does not pan it; instead, it moves the cursor.
The points on the chart represent thermodynamic states. Currently, there is a single red point, which serves as the default and is positioned over a critical point.
To view the list of all existing points, open the Points module. The Points module is docked in the same block as the Chart module. To place them side-by-side, drag the tab of the new module and dock it on the right side.
The module with the list of points still seems too wide. Narrow it down by dragging the separator. Note that only the arrow icon can be dragged, not the whole separator.
The list of points currently holds a single point, corresponding to a critical point on the chart. To create a point, click on the chart. Two points are now visible on the chart and in the list. Another point can also be created by clicking the plus icon at the end of the list. By default, all new points are created at the critical point. This means that we now have two points corresponding to the critical point. Those points are placed on top of each other, so we should remove one of them.
Each point has a unique name, and points can be renamed. The name of a point may not contain spaces or special characters. The points can be sorted alphabetically.
Let's now further investigate the thermodynamic properties of a point. To do that, open the Calculator module. Move the Calculator module below the list of points. It is obvious that one of the points on the chart is larger than the other. The larger point is currently selected, and its properties are displayed in the Calculator module.
To choose another point, click on it in the chart or select it from the list of points. Notice that the thermodynamic properties in the calculator updated as soon as different points were selected.
The Calculator module has two sections: Input and Output. The 'Input' section is a list of two properties that define the current thermodynamic state. Properties of a point can be changed manually.
Let's update the properties of the critical point. Select the temperature field and start typing enthalpy. Select specific enthalpy from the suggestions. The value of the property is updated as soon as a new property is defined. It now displays specific enthalpy instead of temperature. Let's set the enthalpy to 5 MJ/kg. When a value input field is selected, only the number gets selected, but not the units. If needed, units can be manually updated as well. Apply changes by pressing Enter or leaving the input field.
Now let's select the pressure field and type only the letter T. Press Enter, and the property will change to temperature, updating the value. Set the temperature to 1500 K. The point on the chart moved to the intersection of the green contour, representing the isotherm, and a gray horizontal line, representing isenthalpy. It is evident that these two lines intersect twice. The point is currently placed over the intersection at a lower density. To move it to the other intersection, select the 2nd derivative. The point has moved to the left intersection, at a higher density.
This concludes the Input section of the Calculator module. Below it, there is the Output section, which holds thermodynamic properties corresponding to the state of the currently selected point. The Output section is currently empty. To add a property, click the plus icon and select the thermodynamic property. Let's add one more output property. As we add density and pressure to the Output section, the values on the right are filled according to the thermodynamic state of the currently selected point.
When another point is selected, all values in the Calculator module update to reflect the thermodynamic state of the newly selected point.
Selecting or creating new points on the chart is simple because the cursor snaps to existing points and contours, including their intersections.
To manage the visibility of contours, open the Groups module. First, let's move the module to a new dock location. The module contains two sections: Physical properties and Custom groups. Each line represents a group of contours or points, with the name of each group in the first column. Only custom groups can be renamed.
The second column holds an eye icon. Clicking this icon toggles the visibility of the group. Let's hide the contours of pressure, density, and entropy from the chart.
The third column contains a snap icon. Clicking this icon toggles if the cursor should snap to the elements of this group. Let's disable snapping to isotherms. The cursor still snaps to the closest isenthalpy line, but does not snap to the intersection of temperature and enthalpy contours.
A new custom group can be created by clicking the plus icon. Notice that the new group was automatically selected. Since this group has no points yet, the list of points is now empty. New points can be added to this group just like before.
Any custom group can be removed by clicking the cross icon next to its name. Let's remove group0. At least one custom group must always exist.
We have gone through all of the major functions of the SteamPlot application. Now we will demonstrate that the application is flexible enough to display multiple charts simultaneously in any desired layout.
This concludes the tutorial. Thank you for using SteamPlot!