GB/T 2429-1988 Calculation method for net heat of combustion of aviation fuels

AI-translated method card — human verification pending. This is not an official translation of the standard. Unclear source values remain unverified; check the original standard and product certificate before use.

Card type: Test method

1. Method number / full title / English name / replacement relationship

• Standard number: GB 2429-88
• Chinese title: Calculation method for net heat of combustion of aviation fuels
• English title: Ariation fuels-Calculation of net heat of combustion (as in the source text, suspected to be an error for Aviation, requires confirmation against the source standard (source-text extraction))
• Replacement relationship: replaces GB 2429-81
• Reference adoption: international standard ISO 3648—1976 "Estimation method for net heat of combustion of aviation fuels"
• UDC number: UDC 85.52; 734061.4 (as in the source text, requires confirmation against the source standard (source-text extraction))
• Approval/implementation: approved by China Petrochemical Corporation 1988-07-27, implemented on 1989-06-01

2. Scope of application and non-applicability

• This standard specifies the method for calculating the net heat of combustion of aviation fuels from their density and aniline point.
• This standard applies to aviation gasoline and various types of jet fuel.
• Not applicable: not provided in the available source.

3. Method principle

This method uses the measured density and aniline point of aviation fuel to calculate, by empirical formulas, the net heat of combustion of aviation gasoline and various types of jet fuel.

4. Reagents and materials (purity / preparation)

Not provided in the available source.

5. Instruments and equipment

Not provided in the available source (only the test method standards GB 1884, GB 262, GB 380 are cited; no specific instruments are listed).

6. Recommended operating conditions

Not provided in the available source.

7. Sampling and sample preparation

Not provided in the available source.

8. Analytical procedure

• 4.1 Determine the density of the test sample according to GB 1884, reading accurately to 0.0002 g/cm³. From the obtained 20℃ density, find the API degree (60°F) from Table 1, taking it accurately to 0.1.
• 4.2 Determine the aniline point of the test sample according to GB 262, reading accurately to 0.1℃. Convert to Fahrenheit aniline point (°F), 1°F = 1.8C (C is the Celsius aniline point) + 32.
• 4.3 Determine the sulfur content of the test sample according to GB 380, taking it accurately to 0.02% (m/m).

9. Qualitative and quantitative determination and calculation formulas

5.1 The net heat of combustion Q of aviation gasoline and various types of jet fuel (Qp or Qr, MJ/kg) is calculated according to the following formula:

5.1.1 The calculation formulas for the net heat of combustion of sulfur-free test samples are shown in Table 2:

Where: Qp— is the net heat of combustion of the sulfur-free test sample, MJ/kg; A— is the Fahrenheit aniline point, °F; G— is API degree (60°F).

5.1.2 The net heat of combustion of a sulfur-containing test sample is calculated according to formula (5): Qr = Qp (1 - 0.01S) + 0.1016S Where: Qr— net heat of combustion of the sulfur-containing test sample, MJ/kg; S— sulfur content of the test sample, % (m/m); 0.1016— thermochemical constant of sulfur compounds.

5.1.3 The net heat of combustion Q of the test sample (MJ/kg) may also be converted to kcal/kg according to the relationship of formula (6) or formula (7): Q = 4.1868×10⁻³ MJ/kg = 1 kcal/kg (International Steam Calorie)……(6) Q = 4.1816×10⁻³ MJ/kg = 1 kcal/kg (20℃ calorie)……(7) (Note: the exponent source-text extraction in the source text is displayed as 10~3; according to the dimensions it should be 10⁻³, requires confirmation against the source standard (source-text extraction))

5.2 The net heat of combustion of aviation gasoline and various types of jet fuel can be found from the aniline gravity product (A×G) and sulfur content of each test sample according to Table 3, 4, 5 and Table 6 (MJ/kg), or according to Table 7, 8, 9 and Table 10 (kcal/kg).

10. Precision

Judge the reliability of the test results according to the following provisions (95% confidence level).

• 6.1 Repeatability: the difference between two results obtained by the same operator in repeated determinations shall not be greater than 0.012 MJ/kg or 3 kcal/kg.
• 6.2 Reproducibility: the difference between two results submitted by two laboratories shall not be greater than 0.035 MJ/kg or 8 kcal/kg.

11. Report

Take the arithmetic mean of the two results of repeated determinations as the net heat of combustion of the test sample.

12. Referenced documents

• GB 262 Test method for aniline point of petroleum products
• GB 380 Test method for sulfur content of petroleum products (lamp method)
• GB 1884 Test method for density of petroleum and liquid petroleum products (hydrometer method)
• ISO 3648—1976 "Estimation method for net heat of combustion of aviation fuels" (reference adoption)

13. Source and verification

This page is an AI translation of the available Chinese method card. Human verification is pending. It is not an official translation of the standard. Check the source standard and product certificate before use.

14. Quick reference Q&A