1. What is Diesel Index?

Definition: Diesel Index is defined as a measure of the ignition quality of a diesel fuel.

Purpose: It helps evaluate the combustion characteristics of diesel fuels, with higher values indicating better ignition quality.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( DI \) — Diesel Index
• \( °API \) — API Gravity (measure of how heavy/light petroleum is compared to water)
• \( AP \) — Diesel Aniline Point in °F (lowest temperature where aniline and diesel mix completely)

Explanation: The API Gravity is multiplied by the Aniline Point (divided by 100) to determine the Diesel Index.

3. Importance of Diesel Index

Details: Diesel Index is crucial for determining fuel quality, with higher values indicating better ignition performance and cetane number.

4. Using the Calculator

Tips: Enter the API Gravity and Diesel Aniline Point in °F. Both values must be greater than 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a good Diesel Index value?
A: Typically, values above 45 indicate good ignition quality, while values below 35 may cause engine knocking.

Q2: How does API Gravity affect diesel quality?
A: Higher API Gravity indicates lighter petroleum fractions which generally have better ignition characteristics.

Q3: What does Aniline Point indicate?
A: Higher Aniline Points correlate with more paraffinic (better burning) and less aromatic (worse burning) content.

Q4: How is Diesel Index related to Cetane Number?
A: Diesel Index is approximately 60-70% of the Cetane Number for most diesel fuels.

Q5: What's the typical range for Diesel Index?
A: Most automotive diesel fuels have Diesel Index values between 30 and 60.