Discharge In Stream By Constant Rate Injection Method Calculator

Formula Used:

\[ Q_s = Q_f \times \frac{(C_1 - C_2)}{(C_2 - C_0)} \]

Constant Discharge Rate at C1 (Qf):

m³/s

High Concentration of Tracer at Section 1 (C1):

Concentration Profile of Tracer at Section 2 (C2):

Initial Concentration of Tracer (C0):

Discharge in Stream (Qs):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is the Constant Rate Injection Method?

The Constant Rate Injection Method is a dilution technique used to measure stream discharge by injecting a tracer at a constant rate and measuring its concentration at different sections downstream. This method provides accurate discharge measurements in various flow conditions.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ Q_s = Q_f \times \frac{(C_1 - C_2)}{(C_2 - C_0)} \]

Where:

\( Q_s \) — Discharge in Stream (m³/s)
\( Q_f \) — Constant Discharge Rate at C1 (m³/s)
\( C_1 \) — High Concentration of Tracer at Section 1
\( C_2 \) — Concentration Profile of Tracer at Section 2
\( C_0 \) — Initial Concentration of Tracer

Explanation: The formula calculates stream discharge based on the principle of mass conservation, where the injected tracer mass equals the mass in the stream flow.

3. Importance of Stream Discharge Measurement

Details: Accurate stream discharge measurement is crucial for water resource management, flood forecasting, environmental monitoring, and hydraulic engineering projects.

4. Using the Calculator

Tips: Enter all concentration values in consistent units. Ensure C2 > C0 for valid calculation. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What types of tracers are commonly used?
A: Common tracers include fluorescent dyes, salts (like NaCl), and radioactive isotopes, depending on the specific application and environmental regulations.

Q2: How far should the measurement sections be apart?
A: Sections should be sufficiently far apart to ensure complete mixing of the tracer, typically 10-20 times the stream width.

Q3: What are the advantages of this method?
A: This method provides accurate results, is relatively simple to implement, and can be used in various stream conditions.

Q4: Are there limitations to this method?
A: The method requires complete mixing of the tracer, may not be suitable for very large rivers, and requires careful measurement of tracer concentrations.

Q5: How does this compare to other discharge measurement methods?
A: Compared to velocity-area methods, this technique often provides more accurate results, especially in complex flow conditions.