The advantages of ejectors - simplicity, reliability, low weight and low capital cost - can be diminished when condensers are used and a water ring pump is added, particularly in view of the high consumption levels of cooling water or power.

JetSelect 3.0 has been developed to take the guesswork out of purchasing vacuum producers.
 

• Facilitates effective selection of vacuum producers at the pre-purchase stage.
• Establishes the optimum configuration of ejectors/condensers and a water ring pump, if desired, for your requirements.
• Evaluates operating costs in context of forecast maintenance costs and life expectancy of the vacuum producer.
• Ensures efficient use of resources used to achieve performance requirements.
• Eliminates the time spent performing tedious and complicated calculations when evaluating the merits of purchasing a new system.
• Multi-currency facility allows costs to be calculated in US$, British pounds or any other user defined currency.

JetSelect will be of particular use to process engineers, plant engineers and energy managers with an interest in saving money and achieving better plant performance.

Software Specification
The software comprises a number of dedicated multi-page spreadsheets which are run under Microsoft Excel 2000 or 2003 for Windows 95/98/NT4/2000/XP based IBM compatible PCs.

Four versions of JetSelect 3.0 are supplied:

1. JetSelect with Surface Condensers
2. JetSelect with Direct Condensers
3. JetSelect with Surface Condensers with Water Ring Pump
4. JetSelect with Direct Condensers with Water Ring Pump

All software is supplied on CD or via email.
A 30 day e-mail and fax support service is provided.
The software comes with comprehensive electronic documentation and examples.
Please note that Microsoft Excel is not supplied with JetSelect.

Click here to download an example. File size is 466Kb.

Software Application
Click here to view a list of applications for which JetSelect can be used.

Four Stage Systems
In-line arrangements of ejectors and inter-stage condenser with an after-condenser (direct or surface) can be evaluated for suitability and value for money.

The compression of each stage is limited to the key practical values between 1.6 and 10. Motive steam expansion is limited to values between 10 and 8000. Condensers are water-cooled and parallel water supply used. Separate programs are provided for systems with surface and direct condensers and those using water ring pump for the final stage.

Five Stage Systems
A separate page allows an independent single stage to be examined for compression between 5 and 10 and for motive steam expansion between 8000 and 1,000,000. This can be used to evaluate 5 stage ejector systems where the above limitations practically apply.

Principle of Operation
This system’s modus operandi is to establish the optimum value for pressure at each outlet stage against the parameter that it is desired to optimise, usually the monetary parameter. Motive steam consumption, although frequently used as a performance yardstick, is not an indicator of lowest costs of operation. Other factors must be taken into account, namely, all the major costs of a vacuum producer and the actual cooling water costs. If required, process plant and vacuum producer air leakages can be introduced and their effect tested.

Source of Data
The performance of the ejectors is based on the graphical correlation of compression with motive steam expansion to produce the entrainment ratio. The raw data is based on practical performance data published in International Chemical Engineering and has been tested against ejector manufacturers and other published data.

Please Note: This software is not a design tool for ejectors or condensers but evaluates the different aspects of ejector sizing. Where the system proposed input values these should only be treated as guideline values. Only the conventional single nozzle designs, in-line with conical inlet and exit are considered.
 

• SC1 Summary sheet - general contents of the spreadsheets
• SC2 Input gas composition and conditions - on this sheet the composition and the conditions of the suction mixture are selected.
• SC3 Operating parameters of ejectors and condensers - the ejectors and condenser are selected and modifies to establish a preferred arrangement; up to 4 ejectors in series can be chosen; three inter-stage condensers and one after-condenser can be added.
• SC4 Summary of arrangement of component parts of vacuum producer, their main thermal parameters, utility requirements and operating costs. This sheet can be used from the very beginning, as it will demonstrate the progress to the complete system. As all the cost are added the cost of the total operation will emerge.
• SC5 Cost relationships of Ejectors, condensers and CW pumps - The costs of these component parts of the system can be selected considering different materials of construction.: the installation factors can also be selected and approximated costs for the system determined.
• SC6 Operating costs of ejector systems - the costs of the utilities are entered in this sheet; the factors for determination of annualised plant and its maintenance costs can be determined.
• SC7 Estimate of approximate sizes of ejectors - the sizes for the different components are given: the size of the steam nozzle and the diffuser details can be checked as well as the inlet/outlet nozzle sizes as well as entry and exit pressure losses are evaluated.
• SC8 High expansion ejector stage - 5^th stage - this independent sheet allows the user to consider the possibility of adding an additional front stage. The addition of this stage would extent the application of a vacuum producing system to 0.01 mbar.
• SC9 Selection of optimal conditions - in this sheet, using the One and Two Data Inputs Tables or the Solver with the input and calculated data from sheet SC3 are used for optimisation. The calculated relationships can be tabulated and then used for graphic presentation The Excel is very useful in this kind of evaluations.
• SC10 Testing of an ejector stage - this stand alone sheet can be used to examine an ejector stage for its performance in isolation.
• SC11 Air leakage in vacuum tightness - three different and simple methods is given to estimate and determine the level of air leakage. The calculated air leakage values can be considered in the main system calculations in sheet SC3.
• SC12 Saturation in vapour/gas mixtures - the composition of the gas/vapour mixtures generally and at the condensers are evaluated with the aid of this sheet. Condensation conditions for some other selected vapours than water vapour can also be considered. Other vapours where vapour pressure vs. temperature relationships are known can be added.

• ESW1 Summary sheet - general contents of the spreadsheets
• ESW2 Input gas composition and conditions - on this sheet the composition and the conditions of the suction mixture are selected.
• ESW3 Operating parameters of ejectors, Water Ring Pump (WRP) and condensers - the ejectors and condenser are selected and modified to establish a preferred arrangement; up to 3 ejectors in series can be chosen; three inter-stage condensers can be added. The WRP is in the last stage. The WRP can be a single or a double stage.
• ESW4 Summary of arrangement of component parts of vacuum producer, their main thermal parameters, utility requirements and operating costs. This sheet can be used from the very beginning, as it will demonstrate the progress to the complete system. As all the cost are added the cost of the total operation will emerge.
• ESW5 Cost relationships of Ejectors, condensers and CW pumps - The costs of these component parts of the system can be selected considering different materials of construction.: the installation factors can also be selected and approximated costs for the system determined.
• ESW6 Operating costs of ejector systems - the costs of the utilities are entered in this sheet; the factors for determination of annualised plant and its maintenance costs can be determined.
• ESW7 Estimate of approximate sizes of ejectors - the sizes for the different components are given: the size of the steam nozzle and the diffuser details can be checked as well as the inlet/outlet nozzle sizes as well as entry and exit pressure losses are evaluated.
• ESW8 High expansion ejector stage - 5^th stage - this independent sheet allows the user to consider the possibility of adding an additional front stage. The addition of this stage would extent the application of a vacuum producing system to 0.005 mbar.
• ESW9 Selection of optimal conditions - in this sheet, using the One and Two Data Inputs Tables or the Solver and the input and calculated data from sheet SC3 are used for optimisation. The calculated relationships can be tabulated and then used for graphic presentation The Excel is very useful in this kind of evaluations.
• ESW10 Testing of an ejector stage - this stand alone sheet can be used to examine an ejector stage for its performance in isolation.
• ESW11 Air leakage in vacuum tightness - three different and simple methods is given to estimate and determine the level of air leakage. The calculated air leakage values can be considered in the main system calculations in sheet SC3.
• ESW12 Saturation in vapour/gas mixtures - the composition of the gas/vapour mixtures generally and at the condensers are evaluated with the aid of this sheet. Condensation conditions for some other selected vapours than water vapour can also be considered. Other vapours where vapour pressure vs. temperature relationships are known can be added.

• ECD1 Summary sheet - general contents of the spreadsheets
• ECD2 Input gas composition and conditions - on this sheet the composition and the conditions of the suction mixture are selected.
• ECD3 Operating parameters of ejectors and condensers - the ejectors and condenser are selected and modifies to establish a preferred arrangement; up to 4 ejectors in series can be chosen; three inter-stage condensers and one after condenser can be added.
• ECD4 Summary of arrangement of component parts of vacuum producer, their main thermal parameters, utility requirements and operating costs. This sheet can be used from the very beginning, as it will demonstrate the progress to the complete system. As all the cost are added the cost of the total operation will emerge.
• ECD5 Cost relationships of Ejectors, condensers and CW pumps - The costs of these component parts of the system can be selected considering different materials of construction.: the installation factors can also be selected and approximated costs for the system determined.
• ECD6 Operating costs of ejector systems - the costs of the utilities are entered in this sheet; the factors for determination of annualised plant and its maintenance costs can be determined.
• ECD7 Estimate of approximate sizes of ejectors - the sizes for the different components are given: the size of the steam nozzle and the diffuser details can be checked as well as the inlet/outlet nozzle sizes as well as entry and exit pressure losses are evaluated.
• ECD8 High expansion ejector stage - 5^th stage - this independent sheet allows the user to consider the possibility of adding an additional front stage. The addition of this stage would extent the application of a vacuum producing system to 0.01 mbar.
• ECD9 Selection of optimal conditions - in this sheet, using the One and Two Data Inputs Tables or the Solver and the input and calculated data from sheet SC3 are used for optimisation. The calculated relationships can be tabulated and then used for graphic presentation The Excel is very useful in this kind of evaluations.
• ECD10 Air leakage in vacuum tightness - three different and simple methods is given to estimate and determine the level of air leakage. The calculated air leakage values can be considered in the main system calculations in sheet SC3.
• ECD11 Saturation in vapour/gas mixtures - the composition of the gas/vapour mixtures generally and at the condensers are evaluated with the aid of this sheet. Condensation conditions for some other selected vapours than water vapour can also be considered. Other vapours where vapour pressure vs. temperature relationships are known can be added.

• EDW1 Summary sheet - general contents of the spreadsheets
• EDW2 Input gas composition and conditions - on this sheet the composition and the conditions of the suction mixture are selected.
• EDW3 Operating parameters of ejectors, water ring pumps (WRP) and condensers - the ejectors and condenser are selected and modified to establish a preferred arrangement; up to 3 ejectors in series can be chosen; three inter-stage condensers can be added. The water ring pump is the last in any arrangement.
• EDW4 Summary of arrangement of component parts of vacuum producer, their main thermal parameters, utility requirements and operating costs. This sheet can be used from the very beginning, as it will demonstrate the progress to the complete system. As all the cost are added the cost of the total operation will emerge.
• EDW5 Cost relationships of Ejectors, WRP, condensers and CW pumps - The costs of these component parts of the system can be selected considering different materials of construction.: the installation factors can also be selected and approximated costs for the system determined.
• EDW6 Operating costs of ejector systems - the costs of the utilities are entered in this sheet; the factors for determination of annualised plant and its maintenance costs can be determined.
• EDW7 Estimate of approximate sizes of ejectors - the sizes for the different components are given: the size of the steam nozzle and the diffuser details can be checked as well as the inlet/outlet nozzle sizes as well as entry d exit pressure losses are evaluated.
• EDW8 High expansion ejector stage - 5^th stage - this independent sheet allows the user to consider the possibility of adding an additional front stage. The addition of this stage would extent the application of a vacuum producing system to 0.01 mbar.
• EDW9 Selection of optimal conditions - in this sheet, using the One and Two Data Inputs Tables or the Solver and the input and calculated data from sheet SC3 are used for optimisation. The calculated relationships can be tabulated and then used for graphic presentation The Excel is very useful in this kind of evaluations.
• EDW10 Air leakage in vacuum tightness - three different and simple methods is given to estimate and determine the level of air leakage. The calculated air leakage values can be considered in the main system calculations in sheet SC3.
• EDW11 Saturation in vapour/gas mixtures - the composition of the gas/vapour mixtures generally and at the condensers are evaluated with the aid of this sheet. Condensation conditions for some other selected vapours than water vapour can also be considered. Other vapours where vapour pressure vs. temperature relationships are known can be added.