# GoldSim Applications

## Models Illustrating the Use of GoldSim in Specific Application Areas

The models in this section of the Model Library illustrate the use of GoldSim within different application areas.

Each model in the Library is assigned to one or more categories. You can narrow the list by selecting a specific category.

# Engineered Systems Modeling

(The categories are also listed in the left navigation panel).

You can also filter the list by entering keywords or phrases into the search field:

• #### Monthly Cumulative Flows

This example shows how to use a vector constructor to generate a vector of month flow rates for integration and other calculations

• #### Population Model Objects

This example illustrates an efficient way (using cloned containers) to model multiple objects of the same type without having to manually reimplement identical model logic.

• #### Earthquake Response

Computation of building displacement or response to the signal created by earthquake ground motion using a Convolution element

• #### Computing Warranty Costs

This model illustrates how to use the Convolution element to compute cumulative warranty costs.

• #### Moving Discrete Items

This simple model illustrates how to move discrete items from one state to another.

• #### Trucking Shipments

This example combines both continuous and discrete dynamics to model the transport of a material by truck to a dock where the material is loaded onto ships.

• #### Managing a Bank Queue

This is a simple discrete events model of the number of tellers and the size of a queue of customers at a bank.

• #### Discrete Model for Manufacturing

This model describes a manufacturing process with the following stages: (1) casting, (2) pre-finish, (3) ‘solution oven’ heat treatment, (4) ‘aging oven’ heat treatment and (5) a finishing process.

• #### Hydropower Revenue Optimization

Demonstration of GoldSim optimization capabilities using a simple reservoir and hydropower model

• #### Gauss-Newton Trend Line Fitting

This model illustrates how to fit a trend line to data using the Gauss-Newton method.

• #### Ito-Process Random Walk Model

A History Generator Element is used to model an Ito-process random walk. The distribution of the future value is lognormal with mean and variance that both increase linearly with time.

• #### Simulating an ATM Queue using Resources

This is a simulation for an ATM machine installed at an event location, where there are frequent customer visits

• #### Mono Lake Water Balance

Water balance model illustrating a negative feedback loop and of the use of scenarios with a dashboard

• #### Pressure, Productivity and Quality

Example model illustrating feedback from pressure and fatigue on productivity and quality

• #### Polya Urn Problem

This simple model simulates the classic Polya urn problem in which stones, either black or white, are randomly selected (with replacement and addition) from a pot.

• #### Inventory Management

A simple inventory management model that illustrates the structural differences between how such a model is constructed in GoldSim, and how it would be constructed using a classic System Dynamics code.

• #### Time Shifting a Time Series

The purpose of this model is to demonstrate time shifting historic data in a Time Series element. This type of model makes it easy to show summary statistics like exceedance probability of annual peak flow rate or mean annual flow rate.

• #### Time Series Shifting Options

This model includes 4 different methods of time shifting to be used in a wider array of applications.

• #### Time Series Element Lookup Functions

This model illustrates how you can reference a Time Series like a lookup function to access future or past values.

• #### Time Series Data Preprocessing

In this example, a SubModel is used to calculate average monthly rainfall amounts from a Time Series element containing rainfall rate data

• #### Comparing Alternatives

Comparison of two alternative technologies accounting for uncertainty and using Scenarios

• #### Marketing Program Pick

Three different types of promotional campaigns are compared across a 180 day campaign period.

• #### Project Simulator

This model illustrate how conditional containers can be used to simulate projects.

• #### Staff Forecast Model

This model simulates employee supply for a company with complex and lengthy training requirements.

• #### FDA Approval Process

This model simulates the process of obtaining FDA approval for a new drug.

• #### eLearning Project

This model simulates 3 tasks within a project and the associated cost to complete it using conditional containers.

• #### What-If Simulation Case Study

Simple ECommerce, decision-making case study using GoldSim "what-if" simulation

• #### Population Dynamics and Chaos

This model illustrates perhaps the most famous example of chaotic behavior: that exhibited by the ´logistic difference´ equation to describe the growth of a population subject to a carrying capacity.

• #### Predator-Prey Models

This example implements several predator-prey models taken from "Modeling the Environment" by Andrew Ford.

• #### Salmon Life Cycle

This is a simple model that simulates the life cycle of a salmon population as it migrates from the stream, to the ocean, and back to the stream. Although the data and model structure are fictional, it does provide a simple example of how such a model could be constructed.

• #### Acute Infection Model

These two models (continuous and discrete) simulate the spread of an acute infection through a population

• #### Pilot Plant Example

Economic analysis of production expansion stratagies including uncertainty

• #### Highway Access Management

Package of models that allows the user to adjust highway access control measures and view the effect of these measures

• #### Population Growth Aging Chain

Example model illustrating population dynamics modeling with Discrete Change elements and Integrator arrays

• #### Aging Chain

Simulate an aging chain using various methods to keep track of the age structure of a stock of material or items.

• #### Adoption and Diffusion of Technology

A logistic growth curve model is employed to simulate the adoption and diffusion of a new idea or technology

• #### Water Supply Trade-Off Analysis

Use GoldSim's scenarios functionality to create a decision support framework for your next project.

• #### College Planner

Simulate the growth of a money market fund plus savings account that represents a college fund. What is the chance of saving enough for your child?

• #### Probability of Buying a Bike

Tutorial model that calculates the probability that Jason can buy a bike given his income and spending

• #### Depreciation Methods

Calculation and comparison of three different depreciation methods

• #### Mortgage Calculator

This simple model can be used to calculate the monthly payment of a fixed-rate mortgage.

• #### Dashboard-Controlled Currencies

This model demonstrates how a user of a dashboard can control currency exchange rates and select which currency to use in a model.

• #### Pricing European Options

This model prices the value of European (fixed exercise date) call and put options for a stock.

• #### Withdrawing From a Retirement Account

Calculate the number of years you can withdraw money from a retirement account with interest and inflation

• #### Adjustable Outlet Structure Discharge

The purpose of this model is to demonstrate how GoldSim can calculate hydraulic functions dynamically.

• #### Fluid Flow in a Countercurrent Pipe Network

This model demonstrates how GoldSim can be used to model fluid flow in a counter-current flow network.

• #### Fluid Flow in a Parallel Flow Pipe Network

This model demonstrates how GoldSim can be used to model fluid flow in a parallel flow network

A script element is used to solve for pumping flow as a function of the total dynamic head on the pump due to headloss.

• #### Trapezoidal Stormwater Drain Design

This model allows design of stormwater drainage channels used to convey design flood discharges associated with storm runoff from the catchment.

• #### Hydrodynamic Force on a Pipe Bend

Calculate the headloss through this pipe bend and the hydrodynamic force on the pipe

• #### Rectangular Sharp-Crested Weir

Calculate flow rate over a sharp-crested rectangular weir and check for proper sizing

• #### Normal Depth in an Open Channel

This static GoldSim model calculates the normal depth in an open channel assuming uniform flow conditions.

• #### Markov Process Rainfall Model

This model simulates a Markov process that randomly switches between a wet state and a dry state to simulate rainfall given some key historic statistics.

• #### Australian Water Balance Model

The GoldSim 11.0 implementation of AWBM for calculating runoff from rainfall on a watershed. This model is used for water yield and water management studies.

• #### Snowmelt Runoff Model (SRM)

This is a GoldSim impleneation of the NRCS WinSRM model for calculating runoff from a snowmelt driven watershed.

• #### Calibrate Snowmelt Runoff

This model demonstrates the use of GoldSim's optimization feature to calibrate a snowmelt model by automatically adjusting parameters to achieve correlation between historic streamflow record and streamflow calculated in the model.

• #### Reservoir - Groundwater Interaction

The interaction between a reservoir and a large aquifer is simulating using a simple seepage model

• #### Muskingum Channel Routing

Reusable model providing a modified Muskingum hydrologic routing formulation

• #### Muskingum Routing with Reservoir Elements

Commonly used Muskingum hydrologic routing is implemented in GoldSim with Reservoir elements

• #### Multiple Catchment Runoff

Watershed runoff is calculated for three catchments using the same function but different inputs

• #### Probabilistic Detention Pond Model

This model presents a pond discharge versus pond capacity optimization problem.

• #### HSPF in GoldSim

This model provides a native GoldSim implementation of the Hydrological Simulation Program Fortran (HSPF).

• #### Generation of a Stochastic Precipitation Record

This model illustrates one way in which GoldSim can be used to generate a stochastic precipitation record.

• #### WGEN Weather Generation Model

Use Markov process to simulate stochastic precipitation events based on a wet state and dry state.

• #### Vector HSPF in GoldSim

This model provides a native GoldSim implementation of the Hydrological Simulation Program Fortran (HSPF) and divides the watershed into multiple subcatchments.

• #### Australian Water Balance Model (Vectors)

Exactly the same implementation as the original AWBM except this has added capability to incorporate multiple subcatchments using GoldSim's array label sets.

• #### Rainfall Generator Calibration

Using the GoldSim optimization module, a rainfall generator is calibrated using historical data

• #### Groundwater Inflow Recharge

This model accounts for rainfall recharge when calculating groundwater inflow in a mine pit using the Dupuit-Forchheimer equation.

• #### Detention Pond With Orifice Outlet

Simulates the inflow and outflow from a pond that controls discharge using a simple orifice in a riser outlet works

• #### Runoff from Multiple Subbasins

Simulate runoff from multiple subbasins in a watershed using AWBM in GoldSim

• #### Triangular Unit Hydrograph

Calculate the direct runoff hydrograph using a triangular unit hydrograph and direct precipitation

• #### Flood Frequency Analysis

Use GoldSim to perform a flood frequency analysis of daily streamflow records using the Log Pearson III distribution

• #### Diving Bell

Simulation of a diving bell released at a specified depth and moving towards the surface where it emerges above the water

• #### Counter-Current Heat Exchanger

This model describes heat transfer in a double-pipe heat exchanger operated in counter-current flow.

• #### Parallel Flow Heat Exchanger

This model describes heat transfer in a double-pipe heat exchanger operated in parallel flow.

• #### Conduction Plates

This model simulates the heating of circuit boards with hot air over four minutes.

• #### Cooling Coffee Example

This is a simple heat transfer model of a cooling cup of coffee.

• #### Parallel Pumps

This model shows how reliability elements can be used to model throughput in an oil pumping facility. Pumps are turned on and off as the desired flow rate changes and pumps fail and are repaired.

• #### Modeling Losses through a System of Pumps

Simple model of calculating production losses through a set of three parallel pumps each with failures and repairs

• #### Widget Processor Model

In this simple model, widgets are processed at a warehouse for 30 days. The widgets arrive at a rate of about once every two hours. It takes a certain amount of time (1.8 hrs) to process each widget and ship it out, and only one widget can be processed at a time.

• #### Grinding Mill Circuit

This reliability model illustrates a typical closed circuit grinding mill circuit, used in many mine processing plants.

• #### Heat Transfer from a Pipeline

This model demonstrates how GoldSim can be used to model heat transfer from a pipeline to the ambient environment.

• #### BTEX Vapor Migration

This model simulates air concentrations of BTEX at a former gas station site.

• #### Performance Assessment Model

Radiological performance assessment (PA) model incorporating many features and processes typical of a PA for a disposal facility for low-level radioactive waste (LLW).

• #### Competing Demands on a Reservoir

This simple model shows one method for allocating competing demands on a Reservoir.

• #### Reservoir with Operating Pools

Operating rules control outflows from a reservoir that contains operating zones divided into surcharge, flood control, conservation, and dead pool zones.

• #### Controlling Reservoir Discharge

This model explores 3 different methods of controlling discharge from a reservoir. The difference between these methods is important to understand for models that contain multiple reservoirs where discharge from one is being sent to another.

• #### Dam Breach Hydrograph

Simulate the breach in a dam as it grows through time and the resulting discharge hydrograph

• #### Dam Breach Risk

Monte Carlo Simulation of the Dam Breach algorithm to calculate risk of failure

• #### Single Pool Reservoir

Simulate the operation of a simple reservoir with an overflow spillway.

• #### Hydropower Model

This model is based on the Great Falls Project, a series of five hydroelectric dams near Great Falls, Montana.

• #### Flow Between Two Reservoirs

This simple example simulates the flow between and the levels of a two-tank system using Bernoulli's theorem.

• #### Simple Reservoir Operations

This model illustrates how several methods for calculating a reservoir discharge can be combined into a single model. The methods includes calculations based on fluid physics, lookup tables and volumetrically under low-level conditions.

• #### Mass Balance Check

Check that inflows, outflows, and changes in storage within your flow model balance.

• #### Reservoir Spillway

Example model illustrating a weir flow calculation for spillway outflow which is limited by available volume for use with long time steps

• #### On - Off Reservoir Discharge

This model demonstrates the use of a Status element to control discharges from a reservoir.

• #### Rio Chama Flow Alternatives

This model incorporates the Scenario Manager to assist with stakeholder evaluations of environmental flow alternatives.

• #### Annual Recurrence Interval

Using a submodel, calculate the recurrence interval and exceedence probability of annual reservoir spill events

• #### Risk Assessment of Lunar Base

This is a model that simulates the performance of a lunar base over its planned 20 year lifespan. It illustrates how GoldSim's Reliability Module can be use to carry out a probabilistic risk assessment of a complex system.

• #### Risk Assessment of Planetary Mission

This is a model that simulates an unmanned scientific mission to another planet. It illustrates how GoldSim's Reliability Module can be used to carry out a probabilistic risk assessment of a complex system.

• #### Number of Days Which Failure Occurs

This model counts the number of days in which some failure occurs. A failure event is defined as a reservoir overflow occurrence for any duration within a single day.

• #### One-Armed Bandit Model

This model simulates a slot machine with 3 reels each having 5 images that wins money if you end up with 3 in a row.

• #### Simple Inventory Models

This model file includes 5 variations on a simple inventory model. In each case, there is an initial inventory, a sinusoidal demand and a production rate that is constant, stochastic or influenced by feedback.

• #### Auto Supply Chain Model

This is a demonstration model of an automobile supply chain. It represents two links in the chain: the OEM and a major tier 1 supplier (in this case, power trains).

• #### Ships with Containers

This model simulates ships entering the harbor where each ship carries a random number of containers.

• #### Forecasted Water Demand

Calculate future, monthly water demands based on current usage and an annual projection

• #### Simulating a Water Conservation Program

Simulate the feedback loop between water sales revenues and funding a conservation program.

• #### Annual Demand Forecast Submodel

This model uses a submodel to estimate a possible shortfall for the coming year in order to set a supply curtailment if needed.

• #### Pond Flow Network

The purpose of this model is to demonstrate the use of GoldSim elements to represent a flow network of multiple storage elements that distribute water for water use. Water enters the system via "Inflow_Data".

• #### Mine Water Balance

Simple but realistic water balance model for a mine

• #### Allocator Element Priorities

Example model providing demonstration of two different priority implementations in an allocator element

• #### Municipal Water Demand

Forecast water demand for multiple entities based on assumed starting conditions and projected rates of change such as population, water prices, and seasonal use adjustments.

• #### Simple Stream Diversion Model

This model demonstrates a simple continuous stream diversion and and a diversion operating for a fixed amount of time each week.

• #### Septage Water & Solids Balance

Simulates filling, operations, and cleaning of septic impoundments after the material is allowed to dry out followed by final disposal at a landfill.

• #### Water Treatment for Acid Mine Drainage

Example of integrating equilibrium chemical processes into GoldSim to represent water treatment for acid mine drainage

• #### One-Dimensional Lake Stratification

Estimation of dynamic lake stratification using a one-dimensional model

• #### Simple Mass Balance

Illustration of a simple mass balance calculation for a flow network for an inert constituent.

• #### Nonpoint Pollutant Buildup and Washoff

This model provides simulation of nonpoint source pollutant buildup and washoff with automated calibration.

• #### Lake Biogeochemical Food Web Model

This is a model of nitrogen, phytoplankton, zooplankton and dissolved oxygen dynamics in a stratified lake.

• #### Pollution Caused by Leachate from Spoil Heap

This model illustrates the simulation of transport and mixing of two contaminants sourced from a spoils heap.

• #### Simple Mixing Chemistry Equilibria Using Lookup Tables

Simple mixing chemistry equilibria model which uses lookup tables to link to PHREEQC

• #### Solubility Calculation

Example model showing an approach for calculating the solubility of an element based on equilibrium chemistry

• #### Simple Financial Model

This model provides a simple financial simulation of a company.

• #### Cash Flow Alternatives

Simulating production scenarios to help decide whether to replace or repair a widget production system

• #### Operate Two Out of Three Machines

Illustration of logic to keep a specified number of Reliability Module components operating at given times

• #### Simulating Failure Risk of a Pump Station

Use the Reliability Module of GoldSim to calculate the failure modes of various components of a pumping station and water delivery system.