DH4 Guide - Derail Valley Simulator

hi guys school here and welcome to another derail Valley simulator video on this one we're going to focus on one of the new locomotives in Dira Valley simulator which is this the dh4 the dh4 is a four axle diesel hydraulic locomotive what does that mean how does this Loco produce propulsion let's find out so the dh4 has a diesel internal combustion engine and that's what produces the power but how does the power get down to the wheels well the diesel engine is connected via a hydraulic transmission hence the term diesel hydraulic how does that actually work well the hydraulic transmission is basically a torque converter in the case of the dh4 it actually has three torque converters but what exactly is a torque converter and how does it work well let's get us started up first and then we'll discuss right so welcome to the cab of the dh4 it's proper old school isn't it isn't it lovely right it's okay so let's start back here so the handbrake is on it's here this is uh the circuit breaker such that it is there's only two the electrics and the starter so we'll pop we'll pop both of those on then we come down to here and we can see that it has a starter button and a fuel cut off so a bit of a strange position because you can accidentally press one instead of the other but hey ho you hold the start button down and you'll see a few things happen we'll come back to this dial in a second but briefly you've got the sand the fuel and the oil levels you've then got the oil temperature again we'll discuss that in a second and then we discussed the brake pipe in the main reservoir in the braking video so over here cab lights on so we can see what we're doing we'll put one stage of forward and one stage of backward lights wipers we don't need and sander we don't need there's also the speedometer that's how we get it started basic controls we have the independent brake over here and we have the train brake over here down here we have the throttle and reverser and then we also have the dynamic brake which we'll cover in a second finally down here we have a wheel slip light if you're getting a wheel slip the brake pipe pressure is built up but you know the lights flashing because the hand brakes on so we'll turn that off oh that's pretty much it okay so let's discuss how a torque converter works okay so in order to understand what these two dials are telling you and how to drive this locomotive we need to understand what the torque converter is so the torque converter basically uses fluid to transmit the rotating mechanical Power of the engine to the drive Wheels it's an enclosed device at one end is an impeller pump that impeller pump is spun or driven by the engine at the other end is a turbine which is like a big fan and that drives the wheels and in between is fluid and fluid connects to two so when you operate this throttle here it will cause the engine RPM to rise and the engine RPM is shown here by the white needle it's currently idling if you then Engage The reverser that will then cause that pump to start spinning so the engine will start to turn the pump when it turns the pump it starts to spin the fluid inside the torque converter and the spinning of the fluid then starts to press up against the turbine and spin that which causes the wheels to turn hopefully that made some sense so what that means is the engine and the wheels are not directly mechanically linked they're linked by this fluid but it also means that the engine runs independently of the wheels and therefore the engine can't stall what this needle down here shows you is the engine RPM or how quickly you're spinning the the engine so if the reverse is engaged how quickly you're spinning the fluid in the torque converter and then at the other side of that torque converter is how quickly the turbine is now spinning that's trying to drive the wheels now normally the white one will be ahead of the red one because the engine is trying to spin the fluid and this thing will be trying to catch up via the fluid spin so what we'll do is we'll have a quick demonstration we'll release the brakes and we'll well I've already engaged the the reverser so I'll put the throttle let me just sit back so you can see all of what's going on here we'll bring the throttle back into the first position you can watch the engine RPM will start to rise and then what you'll see is the turbine try and catch up and as it tries to catch up it will be spinning the wheels don't forget the red is connected to the wheels so we'll pin that back up goes the RPM and notice the turbine speed is starting to rise as it tries to catch up to the speed of the spinning fluid which is driven by the engine equally if we press it a bit more it will try to spin up a bit more and then we'll just back off and now the wheels are spinning and the fluid is spinning the wheels will never quite catch up with the engine RPM usually but that's like the basics of how it works so let's just head the brakes in so we'll put this into reverse and we'll start to do the same thing I'll release the brake now even though we're going reverse the principles are all the same the engine RPM the turbine RPM it's all the same it's still spinning the fluid inside the torque converter what we're going to do is we're going to reverse back here and we'll attach to some cars and then I'll show you what it's like when it's driving under load now the important things to understand is that the higher the difference between these two needles in other words at the end of the of the torque converter the fluid is spinning that quickly and at the other end is spinning that quickly the bigger the difference the greater the fluid friction inside the torque converter and the more rapidly heat will be generated now due to some kind of weird fluid dynamics when the wheels are going quite slowly and the engine RPMs start to increase what the torque converter actually does is increase its torque output it's it's like I say it's all fluid Dynamic Shenanigans which you don't need to worry about but the bottom line is that this thing is like this weird automatic gear oops we need to come back in that and shove it back a little bit I seems to have bounced so yeah when this thing starts to move it actually increases its torque amounts inside the torque converter so it has more pulling power so the heavier the load the more Target starts to generate but because of the big difference between those needles it also starts to generate a lot of heat and what that means for you as an operator practically speaking I can just flick that and flick that is that you have to keep your eye on the heat that's being generated by the fluid inside the torque converter because if the temperature gets high enough you'll actually destroy the torque converter and that will be very expensive indeed so once the brakes are released we shall head out okay brakes are released put the reverser into the four position I'm gonna throttle it up and I'm going to throttle it up quite a bit what I want you to pay attention to is how high the engine RPMs start to get relative to this this will take a while to come up now because we've got a lot of load behind it so it's going to take a lot of time to spin the wheels and thus the turbine but the engine RPMs are going to increase rapidly and they're going to produce a lot of torque but watch that temperature needle start to climb [Music] there we go so high temperature is being generated very quickly imagine if you're going up a hill it won't take a long time for this thing to start to heat up so you'll have to govern how much throttle you give it just like any Hill Climb because your transmission fluid the fluid inside the torque converter will start to generate a lot of heat when there's a big difference between those two needles and that is basically how you operate the diesel hydraulic I mentioned earlier that the dh4 has a dynamic brake like most dynamic brakes it's not that effective at low speeds but it can break the assist you trying to control your speed on a long descent such as what we can up to now and the way it works is is quite simple first of all you remove all your throttle second thing is you make sure your verses go in the direction of your travel and the next thing that you do is engage the dynamic break so you'll see our speed here is starting to pick up as we go down this descent so I'll operate the dynamic brake there's a few stages you can go through but I'll just put it on Max just to show you what happens pay attention to the temperature needle which is starting to rise it generates heat when we do this but you'll see that light come on shortly when the cooling fan activates so whether you're generating heat because you're operating the engine or whether you're generating heat because you're using the dynamic brake the cooling fan will help to keep your temperature under control but obviously there are limits how does this Dynamic brake work well what actually happens it's a bit technical but it modifies the structure of the coupling in the torque converter so that it basically shrinks the fluid housing volume which introduces extra friction to the fluid that's trying to move inside and that fluid that well the friction slows the wheels down but that generates a lot of heat and that heat you can see dissipates here if you're wondering where the fan is it's actually on the uh as far as I could tell it doesn't actually spin when you look at it but you can see it's pretty effective so that's the dynamic break just don't forget to uh turn it off when you want to carry on I mentioned earlier that the dh4 actually has three torque converters so how do you use them what are they used for well each of them effectively are like big gears they have different ratios so the way that you operate them is actually quite interesting there's no switch or lever in here to operate the torque converters and change one to the other it's all automated it's quite clever actually so what we'll do is we will start by let me get rid of the controls here we'll put the reverser into forward and we shall basically throttle up but what I want you to do is look at the white needle so the white needle Rises it's using the first torque converter the wheels are starting to catch up notice that drop and then a rise again that's like a gear shift that's basically it moving from the first torque converter to the second and if you watch again it does the same again so that's Now using the third torque converter this happens automatically as speed picks up you can see we're already doing 60ks there's nothing after the third one so the maximum speed is dictated by the ratio of that third tall converter but you can see we're already doing 70 which in derail Valley is absolutely plenty but that makes this thing easy to drive there's no gears to worry about all you've got to do is throttle up and pay attention to the temperatures a really nice drive to drive this thing no you may also be wondering when we're traveling at speed what happens if we back off on the throttle what happens to those needles well we'll just back off before we overheat the engine and you can see the white needle at the bottom here which is the engine RPM is now lower than the turbines RPM remember the fluid is still spinning so the engine RPM can't fully come back down to its normal idle of about 600 but equally the turbine RPM is slowly coming back as the vehicle slows down they always try and stay together but they're never actually quite managed to achieve it so in summary the dh4 is in fact a really fun locomotive to drive it's available in the game at 50 000 license which basically is more than the dm3 the dm3 is what we'll look at next the dm3 costs 30 000 but it's more complicated to drive the dn3 for fifty thousand dollars this is now a great intermediate step between the de2 and the D6 this thing is simple to operate fairly easy to understand and it's a lot of fun to drive that is the dh4 hope you enjoyed the video guys give me a thumbs up if you did on to the next one happy training

Channel: Squirrel

Views: 78,028

Keywords: simulator, gameplay, commentary, walkthrough, tutorial, asus

Id: 976I6nF4tIw

Length: 13min 33sec (813 seconds)

Published: Mon Jun 26 2023