Steam Locomotive - Extended HUD

Aim - To describe the information found on the extended heads up display (HUD) for a steam locomotive in Open Rails.

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Index

Introduction

Key Inputs

Steam Production

Steam Usage

Fireman

Performance

Slip Monitoring


Introduction

In relation to the driving of a steam locomotive, the heads up display (HUD) provides information for the locomotive driver that assists them in determining the current state and performance of the locomotive. There are two HUD types in Open Rails, the main HUD which provides sufficient information on the current status of the locomotive for the purpose of driving the locomotive, and the extended steam HUD which provides more detailed information which is primarily desgined for advanced users to configure a locomotive or debug performance issues. For information on the main HUD refer to the Open Rails manual. The information and significance of the detail on the extended steam locomotive HUD will be described below.

The extended steam HUD can be accessed, once the main HUD is visible, pressing "Shft F5" a number of times until it appears. It will look like the picture below.

Extended Steam HUD

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Key Inputs

Provides information of the key input parameters read from the ENG file.

Line 1 - Locomotive Type

This line describes the type of steam locomotive that Open Rails has loaded. The type of locomotive is based upon user defined ENG file parameters, if these are not present in the ENG file, OR will make assumptiuons in reagrd to the type of locomotive.

Line 2 - Input

This line provides information related to the key inputs used to define the locomotive, and will confirm the values that Open Rails is using.

They are from left to right:

  • Evap - the evaporation area in sq ft. This will determine the effectiveness of steam production.
  • Grate - the grate area of the firebox.
  • Boil - Boiler - the volume of the boiler. If this value is too small, then the ability to maintain water levels might be an issue.
  • Sup - Superheater Area - size of the superheater element.
  • FuelCal - Fuel calorific.
Line 3 - Adj (Adjustments)

This line provides information related to the values assigned to "advanced configuration" physics parameters.

They are from left to right:

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Steam Production

Provides information related to the production of steam within the locomotive. The figure shown level with the steam production heading is the total current steam generation rate. If this value is exceeded by the steam usage rate for long periods, then steam pressure will drop.

Line 1 - Boiler

This line provides information related to the boiler.

They are from left to right:

  • Power - the calculated current power of the boiler.
  • Mass - the current mass of water and steam in the boiler.
  • Out - the maximum estimated steam generation rate.
  • BoilerEff - current boiler efficiency factor (between 0.0 - 1.0).
Line 2 - Heat

This line provides related to the boiler heat.

They are from left to right:

  • In - the amount of heat being added to the boiler.
  • Out - the amount of heat being taken from the boiler.
  • Stored - the current total heat in the boiler. Ideally this should be maintained below the value in the next HUD parameter.
  • Max - the maximum calculated heat in the boiler at the maximum working pressure of the boiler.
Line 3 - Temp

This line provides related to the working temperatures of the boiler.

They are from left to right:

  • Flue - the flue temperature.
  • Water - the water temperature.
  • MaxSupH - the maximum superheat temperature that the locomotive will operate at.
  • CurSupH - the current superheat temperature of the locomotive.
  • SupFact - SuperheaterSteamUsageFactor - reduces steam usage for superheating or increases it for allowance for cylinder steam condensation.

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Steam Usage

Provides information related to the usage of the steam within the locomotive. The figure shown level with the steam usage heading is the summed total steam usage.

Line 1 - Usage

This line provides the actual steam usage figures in lbs/h for the various devices that use steam.

They are from left to right:

  • Cyl - steam cylinder - usage will increase dependent upon speed of the locomotive and cutoff (reverser).
  • Blower - Blower - typically only used when the locomotive is stationary.
  • Radiation - Radiation loss - Equivalent loss of heat due to radiation from boiler - a constant value.
  • Comprsr - Air compressor - steam usage.
  • SafetyV - Safety valve - Steam exhausted through the safety valves - only occurs when in manual firing mode, and will be dependent upon the assessed number of valves venting and their size.
  • CylCock - Cylinder cock - Steam escaping from the cylinder cock.
  • Genertr - Generator - steam usage for generate used to produce electricity for lighting, etc.
  • Stoke - Mechanical Stoker - Steam used by the mechanical stoker - only occurs when a mechanical stoker fitted.
  • MaxSafe - Safety Valves Installed - shows the maximum possible amount of steam exhaust that can be released to the air if the steam safety valves "let go". The figures in the brackets indicate the number and size of safety valves assumed to be fitted to the locomotive.
Line 2 - Press

This line provides a view of the steam pressures associated with the operation of the locomotive. In particular, steam pressures relevant to the steam indicator drawing are shown in this line.

They are from left to right:

Line 3 - Status

This line provides the status of various steam usage events.

They are from left to right:

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Fireman

Provides information related to the fireman and how combustion is working within the locomotive.

Line 1 - Fire

This line provides the status of various information related to the fire.

They are from left to right:

  • Ideal - Ideal Fire Mass - this indicates the ideal fire mass of fuel given the size of the grate area.
  • Actual - Actual Fire Mass - this is the current fuel mass. If this fire is less then the ideal mass, then the fire will be "too thin" and burn too quickly, alternatively if it is higher then the ideal, the fire will be "too thick", and will burn slower as the draught will be limited due to the fire thickness.
  • MaxFireR - Maximum Firing Rate - this is the maximum rate that the fireman can feed fuel onto the fire. At high speeds the fireman may find it difficult to keep fuel up to the fire.
  • FeedRate - Fuel rate - indicates the current rate of fuel being added to the fire. Changes in this rate are not instantaneous, as it would take time for the fireman to adjust to altered conditions.
  • BurnRate - indicates the current rate at which fuel is burning in the firebox. Changes in this rate are not instantaneous, as it takes time for the fuel to burn.
  • Combust - indicates the current combustion rate per grate size.
Line 2 - Injector

This line provides various information on the operation of the injectors which add water to the boiler.

They are from left to right:

  • Max - indicates the maximum amount of water that the injectors can inject into the boiler in an hour, and the size of the injectors selected for the locomotive.
  • Inj1 - Injector 1 - provides information of the amount of water and the temperature of the water flowing into the boiler. The lower the temperature of the water the more heat "lost", and required to be replaced by the fire.
  • Inj2 - Injector 2 - provides information of the amount of water and the temperature of the water flowing into the boiler. The lower the temperature of the water the more heat "lost", and required to be replaced by the fire.
Line 3 - Tender

This line provides various information related to the locomotive fuel.

They are from left to right:

  • Coal - indicates amount of caol remaining in the tender or coal bunker.
  • Water - indicates the amount of water left in the tender or water tank.
Line 4 - Status

This line provides the status of various events related to the firemans performance.

They are from left to right:

  • CoalOut - indicates that all the coal has been used up in the tender or coal bunker.
  • WaterOut - indicates that all the water has been used up in the tender or water tank.
  • FireOut - indicates that the fire has been allowed to go out.
  • Stoker - indicates locomotive is fitted with a mechanical stoker.
  • Boost - indicates that the fireman is in "boost" mode. Typically a single fireman could only shovel a certain amount of coal per hour. In boost mode the fireman can exceed the normal hourly rate for small periods of time, but not indefinitely.
  • BstReset - indicates that the fireman's boost period has reset.

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Performance

Provides information related to the performance of the locomotive, and mainly focuses on the relevant forces associated with the locomotive.

Line 1 - Power

This line provides information on the power of the locomotive.

They are from left to right:

  • MaxInd - Maximum Indicated Power - indicates the maximum theoretical indicated power of the locomotive.
  • Ind - Indicated power - actual current indicated power that the locomotive is operating at.
  • Drawbar - Drawbar power - indicates the current Drawbar power that the locomotive is operating at.
Line 2 - Force

This line provides information on the relevant forces of the locomotive.

They are from left to right:

  • TheorTE - Theoretical Tractive Effort - is the maximum theoretical tractive effort of the locomotive.
  • StartTE - Starting Tractive Effort - is the measured tractive effort when the locomotive starts to move.
  • TE - Tractive Effort - indicates the current tractive effort as the locomotive is in operation.
  • Draw - Drawbar Force - indicates the current force at the drawbar as the locomotive is operating.
  • Critic - Critical Speed Tractive Effort - indicates calculated tractive effort at the critical speed of the locomotive.
  • Crit Speed - Critical Speed - indicates the calculated critical speed of the locomotive. This is the point where maximum power was reached, and was based upon the capabilities of the piston. Typically a saturated locomotive reached this point when the psiton was operating at 700 ft/min, and a superheated locomotive when piston speed was 1000 ft/min.
Line 3 - Move

This line provides information related to the movement of the locomotive.

They are from left to right:

  • Piston - Piston Speed - indicates the current speed of the steam piston.
  • SpdFact - Speed Factor - indicates current speed factor of the locomotive.
  • DrvWhl - Drivewheel Revolutions - indicates the current drivewheel revolutions.
  • MF-Gear - Motive Force Gear Factor - indicates the factor used to adjust tractive effort due any gearing of the locomotive.

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Slip Monitor

Provides information related to the possibility of the locomotive slipping. This is a monitoring only function at the moment.

Line 1 - Slip

This line provides information on the forces that may cause the locomotive to slip.

They are from left to right:

  • Piston - Piston Force - indicates the current force exerted by the steam piston.
  • Tang(c) - Wheel cranking force - indicates current cranking force applied to the wheel.
  • Tang(t) - Wheel tread force - indicates the current force at the wheel tread.
  • Static - Wheel Static Friction Force - indicates the force on the adhesive force on the wheel due to adhesion.
  • Coeff - Coefficient of Friction - indicates current coefficient of friction. This will vary depending upon whether the rails are wet or dry, etc.
  • Slip - Slip Indicator - indicates whether the locomotive is slipping or not. Slip will occur if Wheel tread force > Wheel Static Friction Force.
  • WheelM - Drive Wheel mass - weight on the drive wheels.
  • FoA - Factor of Adhesion - indicates the calculated factor of adhesion for the locomotive, ideally to prevent slippage this should be between 4 - 5.

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