My favorite part was "which will give you the wattage needed at the cylinders." Oh course since I am an engineering dummy, perhaps I should ask, "Is steam energy rated in watts?". ~ Gary
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Vance Bass Sent: Tuesday, October 20, 2009 10:08 AM To: Small-scale live steam discussions Subject: Re: [SSLiveSteam] Boiler design question Dave, The right way to do it is to estimate the weight of the train you expect to pull, then gauge the force needed to pull it, multiply that by the efficiency of the typical steam loco of that size, which will give you the wattage needed at the cylinders. Multiply that by the expected efficiency of the boiler, and you will have the wattage needed at the burner. Take that and divide by the energy provided by the fuel you choose and you'll have the fuel consumption rate you need at the burner. At that point, you'll probably have to experiment with burner tube sizes and wick packing to get the right consumption rate. Or, since you're going to have to experiment anyway, you could just build a burner and see if it's adequate. That seems to be standard procedure. I don't mean to be flip here. The first method is the correct engineering process and I've seen people quote watts output of burners, but in the end, it's probably not worth getting an engineering degree for. You see lots of meths-fired boilers with after-market burners (indicating that the original burner was under-powered) or with one of the wick tubes stopped up (the original was over-powered). Even the "pros" can get it wrong, it seems. So just give it a shot and see what works. If you overbuild, you can always plug up one of the wick tubes. Vance _______________________________________________ SSLiveSteam mailing list Send messages: [email protected] Cancel subscription: http://postfix.45mm.com/mailman/listinfo/sslivesteam Rules: http://www.45mm.com/sslivesteam_guide.html _______________________________________________ SSLiveSteam mailing list Send messages: [email protected] Cancel subscription: http://postfix.45mm.com/mailman/listinfo/sslivesteam Rules: http://www.45mm.com/sslivesteam_guide.html
