Gas Concentration Calculator

Project Overview

The Gas Concentration Calculator is a web application that visualizes the concentration of a gas in a confined space over time. It considers the space volume, gas input flow rate, and ventilation rate to calculate and display the gas concentration evolution.

Mathematical Model

Core Equations

• The concentration change is modeled using mass balance principles.
• [ \frac{dC}{dt} = \left(\frac{Q_{in}}{V}\right) - \left(\frac{Q_{out}}{V}\right) \cdot C ] where:
  • ( C ) = Concentration (ppm)
  • ( t ) = Time (minutes)
  • ( Q_{in} ) = Input flow rate (L/min)
  • ( Q_{out} ) = Ventilation rate (L/min)
  • ( V ) = Space volume (m³)

Assumptions

• Perfect mixing of gas in the space.
• Constant temperature and pressure.
• Initial concentration is zero.
• No chemical reactions or absorption.
• Steady input and ventilation rates.

Units and Conversions

• Space volume: cubic meters (m³)
• Flow rates: liters per minute (L/min)
• Concentration: parts per million (ppm)
• Time: minutes
• Flow rate conversion: 1 m³ = 1000 L

User Interface Requirements

Input Fields

• Space volume (m³)
• Gas input flow rate (L/min)
• Ventilation rate (L/min)
• Simulation duration (up to 6 hours)

Output Display

• Interactive graph showing:
  • X-axis: Time (minutes)
  • Y-axis: Concentration (ppm)
• Real-time calculation updates
• Clear visualization of concentration changes

Functional Requirements

Core Functions

• Input validation for all user entries.
• Calculation of concentration at 5-minute intervals.
• Dynamic graph generation and updates.
• Error handling and user feedback.

Data Processing

• Calculate concentration values for each time step.
• Store calculated values for plotting.
• Update graph in real-time.

Validation Rules

• All input values must be positive numbers.
• Volume must be > 0 m³.
• Flow rates must be ≥ 0 L/min.
• Maximum simulation time: 6 hours (360 minutes).

Technical Specifications

Technologies

• Frontend: HTML5, CSS3, JavaScript
• Graphing: Chart.js or similar library
• No backend required (client-side calculations).

Performance Requirements

• Calculations completed within 1 second.
• Smooth graph updates.
• Responsive design for various screen sizes.

Browser Compatibility

• Support for modern browsers (Chrome, Firefox, Safari, Edge).
• Mobile-responsive design.

Future Considerations

• Additional gas types.
• Variable flow rates.
• Temperature and pressure effects.
• Multiple gas sources.
• Export data functionality.
• Save/load simulation scenarios.

Setup Instructions

1. Clone the repository:

   git clone https://github.com/your-repo/gascalc.git
   cd gascalc

2. Open index.html in a modern web browser to use the application.