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Customer Support>FAQ
- KEYS & INSTALLATION
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GENERAL
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GT PRO
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GT MASTER
- Newer gas turbine vendor performance figures – how do I use them in GT MASTER?
- Can I impose degradation on the gas turbine’s performance?
- Can I part load just one of my two gas turbines, keeping the other at full power?
- Can I model auto-extraction in a steam turbine to maintain a constant extraction pressure?
- How can I make the model produce a particular amount of net power without iterating on gas turbine loading or duct firing?
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STEAM PRO
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STEAM MASTER
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THERMOFLEX
FAQ - KEYS & INSTALLATION
Our experience with the keys we use to enable our programs has proven them to be quite reliable. Occasionally, but rarely, they fail. Far more frequently, they appear to have failed because of some other reason. Some of the more common causes are:
Installation of other software that unfortunately over-writes some portion of the key supporting software.
Installation for the first time on a new computer (particularly without Administrative Privileges on Win NT, Win 2000, or Win XP Professional), or installation of a licensed version after having installed a demonstration version without installing the key's device driver.
Attempting to use two Thermoflow keys simultaneously, which will not work. In general, the keys can be "stacked" with keys of other origins, but the Thermoflow programs will only be able to read that Thermoflow key which is closest to the parallel port of the computer.
In all cases above other than the last, the solution is to install the software once again, carefully.
FAQ - General
Can I export the results of my Thermoflow programs to Excel?
Although Excel, by itself, cannot directly read the files, Thermoflow provides an Excel “Add-In” named E-LINK that lets you connect to an already-computed GT PRO, GT MASTER, STEAM PRO, STEAM MASTER, or THERMOFLEX file. The file’s outputs and also its inputs are accessible from Excel with this feature, and you can use this to drive the Thermoflow program through multiple computations if you choose. See the E-LINK segment of the Volume 4 manual, Applications and Utilities.
FAQ - GT PRO
My gas turbine is not in the GT Selection List.
With over 350 models in place, our GT Selection list is extensive, but it cannot be all-inclusive or prescient. Several responses may apply, depending on circumstances.
1. If the gas turbine is too new to have been included in the list, you’ll need to obtain data from the vendor for your ambient conditions, fuel, expected steam or water injection, and expected inlet and exhaust losses. You can impose their power, heat rate, exhaust flow, and exhaust temperature for any given operating condition in our User-defined gas turbine specification, selected from near the top of the GT Selection list. This specification is useful only at the operating point for which it is defined. Please advise Thermoflow that you are interested in having a model of that engine included, and please also advise the vendor that it would be helpful to you if Thermoflow were provided with enough data to add that model to our list.
2. If the new engine is a minor uprate from an earlier machine, you may be able to ‘tweak’ the model of the earlier engine to represent the performance of the new machine, using the ‘Model Adjustments’ tab of the [GT Inputs] topic. Visit that tab and press the <F1> key of your keyboard to summon HELP.
3. If you have both nominal data and performance correction curves for the engine, then you can use the GT Template program to establish a curve-based model for the engine. When you’ve completed the entries and saved the model, you can select to use that GT Template model from within the [GT Selection] topic of GT PRO or GT MASTER. See the GT Template section of the Volume 4 manual, Applications & Utilities.
GT PRO assumes methane as the fuel, but my natural gas is only partly methane.
Reselect the fuel, at the [GT Inputs] topic. Select ‘User-defined’ from the Fuel Selection entry box, and then click on the ‘Modify Fuel’ button that is enabled. This will bring you to an extensive Fuel Library, which includes the option to specify the fuel yourself by its composition.
Can I preheat the fuel with heat from elsewhere in the plant?
Of course; visit the ‘Fuel Heating and GT Cooling’ tab of the [GT Inputs] topic, and select ‘User-defined’ for the fuel heating model. You’ll be able to specify the desired fuel temperature and direct which hot fluid stream will be tapped to provide heat to the fuel. For further clarification, click <F1> for HELP while in that display. The results will be displayed in a table near the top of the “Gas Turbine” text output.
FAQ - GT MASTER
Newer gas turbine vendor performance figures – how do I use them in GT MASTER?
As in GT PRO, if you know performance figures at just one or a small number of operating conditions, you can re-select the gas turbine to be a User-defined gas turbine and enter the power, heat rate, exhaust flow rate and exhaust temperature for each of the particular cases. If you have performance correction curves, you may want to produce a GT Template representation of the gas turbine. If the performance has minor changes from the existing model, you may be able to ‘tweak’ the model with the ‘Model Adjustments’ tab of the [GT Inputs] topic.
Can I impose degradation on the gas turbine’s performance?
Three separate entries exist to degrade gas turbine performance. These are a reduction in inlet airflow, a reduction in compressor efficiency, and a reduction in turbine (expander) efficiency. Any one, or all, of these will lead to degraded performance. These three effects constitute the first three entries in the the ‘Model Adjustments’ tab of the [GT Inputs] topic.
Can I part load just one of my two gas turbines, keeping the other at full power?
To help keep GT MASTER quick and robust, multiple gas turbines are treated as identical, so part-loading one will cause both to be equally part-loaded. Only one exception exists, when a gas turbine is completely shut down, as directed in the [Main Inputs] topic. THERMOFLEX, however, will let you operate gas turbines independently. To use THERMOFLEX instead of GT MASTER, return to the precursor GT PRO file, import that file to THERMOFLEX, carry it through the design computations and set it to off-design. You will then be able to manage the gas turbines and their HRSGs quite independently.
Can I model auto-extraction in a steam turbine to maintain a constant extraction pressure?
Certainly, by specifying that the steam turbine section downstream of the extraction will have controlled inlet pressure, either in the GT PRO file used as a precursor to the GT MASTER file, or in the GT MASTER file itself. This is done in the ‘Stage Groups and Controls’ tab of the [ST Inputs] topic.
How can I make the model produce a particular amount of net power without iterating on gas turbine loading or duct firing?
Because the net power is a computed output, dependent upon the parameters you cite, it is a candidate for use as the target value of GT MASTER’s Control Loop, which you can invoke from the menu bar while in the GT MASTER input screens. The computation is still iterative, but it lets the computer drive the iteration for you in an automated way.
FAQ - STEAM PRO
How do I make the boiler a CFB (circulating fluidized bed) boiler?
STEAM PRO lets you select a CFB at the beginning [New Session] topic. Either automatically, or with your direction, a limestone is provided with an appropriate flow rate to serve as a sorbent.
STEAM PRO lets you select the primary and alternate fuels from an extensive Fuel Library at the [Plant Criteria] topic. Select from a large number of fuels within the library or select to specify the fuel as a User-defined fuel.
FAQ - STEAM MASTER
When I part load the plant, the computed reheat temperature changes.
This generally occurs when the user has paid little attention to the design of the boiler. The resulting hardware model may have poor regulation of the reheat temperature at conditions other than the nominal full load. If the boiler’s behavior is important to you, then visit the superheater and reheater hardware inputs to revise them. If the boiler’s behavior is not the focus of your efforts, you may instead want to select ‘Black Box’at the Boiler Model selection on the [Main Inputs] topic.
FAQ - THERMOFLEX
The program warns that the desired process flow isn’t delivered. What can I do?
The Process component lets you specify the flow you want, but the program’s internal hierarchy of “flow dictators” will, in some cases, overrule that component’s specification. Typically, if your process stream is fed directly from an evaporator, whose thermodynamic conditions determine the steam production rate, the evaporator’s flow will dictate the flow to the process. To get a better understanding of the workings of this flow dictator hierarchy, please see Chapter 6 of the THERMOFLEX manual.
Is there some way to minimize the time of building a model with many identical groups of components ?
Yes, for repeating groups of components, you will do well to lay out one such group. Select the group, in the Draw mode, by dragging the mouse to produce a rectangle surrounding the group and then press the <F8> key or select Edit/Copy from the menu bar. To save time entering input values for such repeating groups, advance from the Draw mode to the Edit Inputs mode, and specify input values for the original group, then retreat to the Draw mode to copy. The copies produced will include the input values you imposed.