Martin Griffith

Hi Neil, You can get the Error List to reappear by clicking on the yellow (or red) status bar at the bottom of the main form. Out of curiosity, how big is your model and what simulation option are you running?

Hi Görkem, We're not sure how this would have happened. Your settings may have been corrupted. We have released a new version of Pumpsim (version 3.1.4.2) which has re-enabled the opton in the right-click menu and which also automatically enables the toolbars on launch. Install this version and the problem should go away. The new version can be found here: https://pumpsim.com/currentdownloads/ Apologies for the inconvenience caused, please let us know if the problem continues. Martin

If the reference layer being converted has been assigned to a primary or secondary layer (through the option in the import window or by editing the reference layer) then converting it will ask the question if you want the airway layers to inherit from the reference graphics layers. So the Ventsim model you are working with probably has had the reference layers assigned. We will make an improvement for the next version. We can make it so that the question is only ever asked once every time you open Ventsim (similar to the message when you first use the StageLock). And then it can be changed later through the settings if needed. If you have any other suggestions, please let me know. Otherwise, I will update you again when the new version is available

Hi Kingsley, This is a new feature we recently added, where you can break up an imported reference layer by colour and automatically add it to primary and secondary layers. Then when you convert to centreline, you click yes to the question and your airways are automatically assigned to primary and secondary layers. This option should only trigger when the reference layers have been assigned to a primary or secondary layer. To avoid it, when importing the centrelines, make sure that the option highlighted below (Create P/S Layers) is unchecked. I hope this makes the problem go away. If not, please let us know; there are a limited number of circumstances where it may still appear; if so, we will come up with a solution.

Are you able to tell me which version of the software you are using? If possible I would suggest upgrading to the latest version: https://pumpsim.com/currentdownloads/ This should fix the problem. If your license is out of maintenance, then please contact us at ventsim.support@howden.com, telling us what version of the software you are using and your license number.

Hi, Can you send us a screenshot of the problem? Do you have any pumps in the pump database (Tools | Pumps)?

Hi Xiao, When simulating with natural ventilation ONLY, then there can be some inconsistency in results; for example in some circumstances the flow may go in a certain direction only because it began in that direction before starting the simulation. Generally, we recommend turning on the natural ventilation option in a model only once you have a well-configured and reasonably accurate Heat Simulation, since ultimately the flow is driven by differences in air density, created by different temperatures. This would be even more important if it is a natural ventilation ONLY model. For your model, I suggest reviewing your Heat Simulation. You will need to configure the Rock Strata heat correctly, as well as account for any heat sources from underground vehicles or equipment. I suggest the following thread for some tips on configuring the Heat Simulation: That would be the first step. Let us know how you go. Feel free to send through any questions or model.

Hi, At the end of the Fire Simulation, you have the option to return the model to its original state. If you don't, then the very hot temperatures that you might have had from a fire will remain and these can significantly affect the results. That would be my main guess why; check if the temperatures are still very high. If so, you can reset the model or run a new Heat Simulation to get back to normal operating temperatures. That would be my best guess as to what is going on. Let me know how you go.

Hi, I might be wrong, but it looks like the rollback has not been cleared yet in the final screenshot. If the rollback remains in the model and with the very hot fire temperatures, then the Air Simulation will simulate flow through there. Go to Clear Rollback in the menu under the Draw Tool. If that doesn't revert the rollback back to its original form, then you may have to delete the rollback yourself and rebuild the dead end.

We don't have a simple way to do this unfortunately. We are aware that this is an important type of diagram in some countries, so it is something that we are looking to develop in Ventsim in the near future. I will keep you posted on developments we make here.

Hi Xiao, you have a few options. You can set the colours and text to Airflow | Quantity and see the results in the viewer. You can also select the airways you are interested in and then launch the spreadsheet tool (Tools | Spreadsheet). There you can access any properties on the airways and export them to Excel if you want. Or you can select the airways with the Measure tool and generate a graph. Is this the sort of thing you need?

Hi, that doesn't sound good. If you like, send us the model and we can try to to recreate the problem. Or perhaps some screenshots. Fire in a low airflow area can be tricky to model.

Hi, This is a tricky challenge for the fire modelling because there is no initial airflow; in reality the airflow is generated directly from the fire. So you need to introduce some airflow to the fire somehow. One way to do this is to use the Rollback feature. This feature basically breaks up airways into two levels, so that they can have airflow flowing in different directions along the ceiling and along the floor of an airway. Select the dead end, and the under the Draw tool select Construct Rollback. You'll see the airway split up. Try the Fire Simulation now and have a play with it, try different things. Once finished you can Clear Rollback.

Hi Calen, thanks for your message. Firstly, you can extend the dynamic simulation as long as you like with the highlighted button: As for initial concentration and decay time: the concentration of 100 units is a concentration in the airway airflow, it doesn't reflect (directly) the volume of gas in the bottle. To work out the resultant concentration from a given bottle assuming a release over 30 seconds, you would need to know the amount of stench gas in the bottle; ideally a volume at standard density, or a weight. Do you have such information? If so, we should be able to calculate the correct concentration for a given release time and decay. For the questions: i) You can add ethyl mercaptan as a gas if you want. However, the concentrations are generally so low, that other gas concentration do not need to be significantly altered to account for it. The only reason you would model it as a gas is if you simply prefer using the Gas Simulation, or you are running the stench gas simulations alongside some other simulation involving gases, such as a fire simulation. If you want to model it as a gas, then you need to change one of the customisable gas names. There are 5 gases that you can rename; go to the settings to do it. You can't change the units of the gas, you will have to pick the one that has your preferred unit (in your case H2S, HCN and SO2 use ppm, so one of those) Note, that if you stick with the Contaminant Simulation, you can change the Contaminant unit in the Contaminant Settings, if you want. The contaminant can be used to represent anything, a CO ppm, for example. ii) You could rename H2S, HCN and SO2 to different stench gases. But again, your concentrations will tend to be low, so I think it would be fine to run the simulations from different sources independently. iii) Not too sure on this. I think you could try to increase your Dynamic Increment as well. Note that you can control the decimal places on the contaminant in the Unit Settings. Not too sure I follow the problem. Feel free to send a model to ventsim.support@howden.com and will take a look. iv) Not sure I can help with this. I would check with the product manufacturer first. I'll take a look and see if I can find anything.

Hi Jason, Ventsim files are always saved in metric SI units, and then the display units are customisable through the Ventsim UI. So as Florian has said, it is best to export from Deswik in SI metric, open in Ventsim and then change to Imperial in Ventsim. Let us know how this goes.

Hi Calen, thanks for letting us know, we will take a look at this and get back to you.

The new version of Ventsim 5.4.4.4 has this change included. You can download it here: https://ventsim.com/download/minor-releases/ Thank you for your feedback on this.

Ventsim version 5.4.4.4 is available to download here: https://ventsim.com/download/minor-releases/ In this version, Utilization Factors are backwards-compatible. This means models opened in versions earlier than 5.4.3.3 will get the correct adjusted heat (but lose the Utilization Factor).

Hi Manuel, To do this, you just need to build the duct several times, adjusting the horizontal offset. To do three like in your image, you would build three times, with horizontal offsets of -2, 0 and 2.

Hi Kevin, that does look odd. If possible, would you mind sending me the model at ventsim.support@howden.com ? (all models sent are treated confidentially and only used for debugging purposes)

Hi Kevin, Thanks for your question. The two quantities refer to different things. The Outlet Quantity in the Fan Database refers to the quantity airflow discharged from the jet fan (usually expelled at high velocity). The Flow reported in the Fan tab Info box in the Edit Box refers to the airflow in the airway. This airflow will also be dependent on other factors in the model besides the jet fan. As for the power, in the Jet Fan database, the power entered is the Absorbed Power, not the Electrical Power. The value reported in the Fan tab info box is the electrical power, which adjusts for an electric motor efficiency, usually 90 or 95% (Settings | General | Airway Defaults | Efficiency Fan Motor). This should be clearer; in the next version, I will add a note to the Fan Tab Info box that the power reported is electrical.

Ventsim version 5.4.4.4 will be available next week with this change. I'll post here again when the official 5.4.4.4 is available and get you to update to it. Let us know how it goes.

Hi John, Thanks for the suggestion. I've sought to do this in the next version of Ventsim. Currently, it is only the properties Heat | New Heat Input and Heat | Point Diesel Power which do not include inputs from the Activity Tracks (New Latent Heat(/L), New Sensible Heat(/L), and New Total Heat/L already include Activity Track heat). In the next version I will make Heat | New Heat Input and Heat | Point Diesel Power include the Activity Track heat. I will also change the name to Heat | Diesel Power. This should be out tomorrow.

Buenos dias Pablo, Gracias por su sugerencia. Empiezo por enumerar los recursos disponibles actualmente, a pesar de que es posible que ya los conozca: 1/ Hay el webinar de Pumpsim en espanol disponbile aqui: https://ventsim.com/es/webinars/ . Este webinar incluye informacion sobre la programacion desde el minuto cincuenta 2/ Hay el manual. Si su version de Pumpsim no puede acceder al manual espanol, por favor de descargar y instalar la ultima version de Pumpsim, disponible aqui: https://pumpsim.com/es/currentdownloads/ Tambien, vamos a explorar posibilidades de mejorar el interfacie de este parte. Estamos contentos de recibir sugerencias o responder a cualquier duda que tiene. Hay alguna caracteristica especifica que no funciona como le gustaria? Martin

Thanks John, from the next version out this week, models opened in older versions will still lose the Utilization Factor, but the total heat will be adjusted.