 So, what we'll do, we'll take a look at the two different feedwaters separately. The first one that we will look at is the open feedwater heater, so this is part of the regenerative ranking. So, with the open feedwater heater, what we're doing is we're taking steam from the turbine and we're mixing that with the compressed water at state 2 and the mixture is coming together. Another thing that the open feedwater heater does is it helps degasify the feedwater. Remember we talked about saying that you can have corrosion within your boiler due to oxygen being present within the feedwater and with the open feedwater heater, what we're able to do is by agitating through the injection of steam we're able to liberate some of that oxygen or air that might be in the boiler feedwater and consequently through this process what we do is we reduce corrosion within the boiler which is an important thing that we want to be able to do. So, the next thing that we're going to do here is we're going to take a look, a closer look at both the process schematic as well as the process diagram for the Rankin cycle using the regenerative with an open feedwater heater. So, what we have here is our process schematic and diagram and this is very different from the Rankin that we looked at before for the reason that we're stripping fluid off at 0.6 which is coming out of our turbine and what we're going to do is we will say we'll introduce a new parameter here and it'll be a little y and it is going to be equal to the mass flow rate at 6 divided by the mass flow rate of fluid going into the boiler at 5 and consequently what we will be able to do now we'll be able to say that this fluid stream here at 6 is percentage mass fraction y and the fluid normally leaving our turbine will be mass fraction 1 minus y and so we can carry that through and then you'll notice that when we come into our open feedwater heater so let me just circle that we come into the open feedwater heater and we have fluid at y and 1 minus y those come together and based on the way that we've defined the mass flow rate when we exit there we come back to 100% of the mass flow rate so we then show I'll put a little one here don't get a confused mistake one but it's denoting the fact that we're back at 100% mass flow rate and that is what this number one up here signifies that is the mass flow rate of fluid going through the boiler and we denote that as being 1 but then when we strip it off we have to be able to have a way to account for the fact we don't have the full mass flow rate so that's what we're doing there and then if you look at the TS diagram one thing that I'll say whatever you're drawing these always make sure that you go to the saturated a liquid point that's always the starting point for any of these cycles and it will make your life simpler if you ensure that you go to that point so we go there and with this idea of mass fraction y what we have going from 7 to 1 we can write 1 minus y and then what is going from 6 down to 3 is y and so that would be the percentage of mass that we are stripping out and is then going into our open feed water heater so that is the TS diagram as well as the process schematic with the open feed water heater and what is going on here is pump one notice that we have two pumps that's right we have pump one we have pump two that's another thing that's different from what we've looked at before and pump one does not take us all the way up to the boiler pressure pump one only takes us up to state 2 so it's taking us to the intermediate pressure which is the pressure at which we're bleeding the steam off of the turbine so that's an important point of the open feed water regenerative so pump one is taking the liquid up to the pressure of the bleed steam these two liquid streams are coming together and mixing in the open feed water heater they need to be at the same pressure so that's one point that you want to remember so that is the introduction to the cycle the next thing that I want to do and it's going to take a little bit of time is to take a look at the first law and apply it to the open feed water heater and see how the equations change from just the standard rank and cycle so that's what we'll do in the next segment