MIL-PRF-83282 Thermal Expansion Calculator

MIL-PRF-83282 Volumetric Thermal Expansion Coefficient (β)

MIL-PRF-83282 volumetric thermal expansion coefficient vs temperature in degrees F, compared with MIL-PRF-5606

β = −(1/ρ)(dρ/dT), derived from the straight-line fit to the four NADC-79248-60 Table 2 atmospheric densities. The curve is drawn only from 38 °C to 204 °C (100.4–399.2 °F); nothing is extrapolated.

Circles are the four tabulated β values at 38, 93, 149 and 204 °C. The dotted line is the NADC report's own average cubical expansion, 8.3 × 10⁻⁴ /°C over 38–149 °C, shown as a cross-check only. The blue MIL-PRF-5606 series is derived the same way from its own NADC densities, over the same 38–204 °C range. The NADC data are for the 1980 NADC reference lot of MIL-H-83282 (lot and revision not stated).

Toggle data sets by clicking the legend.

MIL-PRF-83282 Percent Volume Change Relative to 100.4 °F (38 °C)

MIL-PRF-83282 percent volume change vs temperature in degrees F relative to 100.4 F, compared with MIL-PRF-5606

ΔV/V₀ = (ρ₀ − ρ) / ρ × 100%, referenced to 100.4 °F (38 °C) where ρ₀ = 829.03 kg/m³ from the same density fit. Negative values mean the oil is denser (contracted) relative to 38 °C.

The reference is 100.4 °F (38 °C) because 38 °C is the lowest temperature with a measured MIL-PRF-83282 density; nothing is extrapolated below it. The blue MIL-PRF-5606 line uses its own 38 °C density as the reference.

Valid 38–204 °C (100.4–399.2 °F) only. Circles are the four tabulated temperatures.

Toggle data sets by clicking the legend.

MIL-PRF-83282 Thermal Expansion Calculator

Degrees (°F):

Degrees (°C):

β × 10⁻⁴ (1/K):

β × 10⁻⁵ (1/K):

β × 10⁻⁶ (ppm/K):

β (1/K):

β (1/°R):

Density, linear fit (kg/m³):

% Vol. Change from 100.4°F:

MIL-PRF-5606 β × 10⁻⁴ (1/K):

Calculator valid 100.4 °F to 399.2 °F (38 °C to 204 °C) only, using the derived fit to the NADC-79248-60 atmospheric densities. Outside that range the result is "Out of Range". The MIL-PRF-5606 row uses its own NADC density fit over the same range.

Thermal Expansion of MIL-PRF-83282 Fire-Resistant Hydraulic Fluid

Volumetric Thermal Expansion Coefficient — β (derived)

The volumetric thermal expansion coefficient β describes how much a fluid expands per degree of temperature rise at constant pressure:

\[ \beta = -\frac{1}{\rho}\,\frac{d\rho}{dT} \]

NADC-79248-60 does not tabulate β for MIL-H-83282. β is therefore derived from its atmospheric density data. The four Table 2 densities are fitted with a least-squares straight line, ρ = 854.002 − 0.65704 · T_°C kg/m³, and because the fit is linear the derivative is constant, giving

\[ \beta(T) = \frac{0.65704}{854.002 - 0.65704\,T_{\text{°C}}}\ \text{1/K} \]

β rises slowly with temperature as density falls: about 7.925 × 10⁻⁴ 1/K at 38 °C (100 °F) and about 9.126 × 10⁻⁴ 1/K at 204 °C (399 °F). MIL-PRF-83282 is a fire-resistant, synthetic hydrocarbon aircraft hydraulic fluid. Like most oils it expands by about 0.08 to 0.09 % per kelvin. The curve is valid only between those two temperatures, the range of the measured densities.

Cross-Check Against the Report's Average

NADC-79248-60 (p.15) gives a single average cubical expansion coefficient of 8.3 × 10⁻⁴ /°C (4.6 × 10⁻⁴ /°F) over 38–149 °C (100–300 °F), with no point values. The average of the derived β over the same interval is 8.296 × 10⁻⁴ /°C, which agrees with the report's value to within 0.1 %. The report does not state how its average was computed, so this is a consistency check only.

Data Source and Range

The density fit is built from the MIL-H-83282 atmospheric column of Table 2 in NADC-79248-60, at 38, 93, 149 and 204 °C (100, 200, 300 and 400 °F). The report's Table 9 covers Nadraul MS-6 rather than MIL-H-83282. No density or expansion data below 38 °C were found in the sources used, so the chart and calculator are not extended below 100.4 °F. Nothing is extrapolated above 399.2 °F either. The report gives no uncertainty for its measurements, and the lot and specification revision are not stated (the 1980 NADC reference lot of MIL-H-83282).

MIL-PRF-83282 — Thermal Expansion vs. Temperature

Temp (°C)	Temp (°F)	Density, linear fit (kg/m³)	β × 10⁻⁴ (1/K)	ΔV/V₀ (%) vs 38 °C	Notes
38	100.4	829.0	7.925	0.000	Tabulated (NADC Table 2, derived)
50	122.0	821.1	8.001	0.960	Fit
60	140.0	814.6	8.066	1.775	Fit
70	158.0	808.0	8.132	2.602	Fit
93	199.4	792.9	8.287	4.558	Tabulated (NADC Table 2, derived)
100	212.0	788.3	8.335	5.168	Fit
125	257.0	771.9	8.512	7.406	Fit
149	300.2	756.1	8.690	9.646	Tabulated (NADC Table 2, derived)
175	347.0	739.0	8.891	12.180	Fit
204	399.2	720.0	9.126	15.149	Tabulated (NADC Table 2, derived)

β = −(1/ρ)(dρ/dT) with ρ = 854.002 − 0.65704 T_°C kg/m³ (straight-line fit to the NADC-79248-60 Table 2 atmospheric densities), valid 38–204 °C only. Tabulated rows are the four β values from the derived data set.

Cross-Check: NADC Average vs. Derived Average

Quantity	Range (°C)	β × 10⁻⁴ (1/K)	Basis
NADC-79248-60 average cubical expansion	38–149	8.3	Report text, p.15 (no method stated)
Mean of derived β over the same range	38–149	8.296	Computed from the density fit

The derived mean is the average of β over the interval, equal to (1/ΔT)·ln(ρ₃₈/ρ₁₄₉) from the same fit. The two values agree to within 0.1 %.

MIL-PRF-83282 vs MIL-PRF-5606

MIL-PRF-83282 is a synthetic hydrocarbon fluid; MIL-PRF-5606 is a petroleum (mineral oil) hydraulic fluid. Both are derived from the same NADC Table 2. Over 38–204 °C, MIL-PRF-83282 has the lower β, by about 0.54 × 10⁻⁴ 1/K (6 %) at 38 °C, narrowing to 0.72 × 10⁻⁴ 1/K (7 %) at 204 °C. Its density slope is a little smaller (−0.657 against −0.713 kg·m⁻³·K⁻¹) and its density is a little lower (about 829 against 842 kg/m³ at 38 °C).

Temp (°C)	Temp (°F)	MIL-PRF-83282 β × 10⁻⁴ (1/K)	MIL-PRF-5606 β × 10⁻⁴ (1/K)	Difference (× 10⁻⁴ 1/K)	Difference (% of MIL-PRF-5606)
38	100.4	7.925	8.463	-0.538	-6.4 %
50	122.0	8.001	8.550	-0.548	-6.4 %
70	158.0	8.132	8.699	-0.567	-6.5 %
93	199.4	8.287	8.876	-0.590	-6.6 %
125	257.0	8.512	9.136	-0.623	-6.8 %
149	300.2	8.690	9.341	-0.651	-7.0 %
175	347.0	8.891	9.573	-0.682	-7.1 %
204	399.2	9.126	9.846	-0.720	-7.3 %

Both columns use the derived fits to the NADC-79248-60 Table 2 atmospheric densities, 38–204 °C only. The MIL-PRF-5606 fit is ρ = 869.517 − 0.71295 · T_°C kg/m³. The lot and specification revision are not stated for either fluid. Differences are computed from the values shown.

Sources

A. A. Conte Jr. and J. L. Hammond, Development of a High Temperature Silicone Base Fire-Resistant Hydraulic Fluid, NADC-79248-60, Naval Air Development Center, Warminster PA, 5 Feb 1980. DTIC ADA081597. apps.dtic.mil/sti/tr/pdf/ADA081597.pdf. Table 2 (MIL-H-83282 and MIL-H-83282 columns) and p.15 (average cubical expansion), accessed 25 Oct 2026.
US Department of Defense, MIL-PRF-83282D, Performance Specification: Hydraulic Fluid, Fire Resistant, Synthetic Hydrocarbon Base, Metric, NATO Code Number H-537, 30 September 1997, with Amendment 1. everyspec.com. Identification of the fluid; no finished-fluid density limit.

The NADC report does not state the specification revision or lot of the MIL-H-83282 tested, and gives no measurement uncertainty. No manufacturer data sheet gives thermal expansion data, and none is used on this page.

MIL-PRF-83282 Fire-Resistant Synthetic Hydrocarbon Hydraulic Fluid Thermal Expansion Coefficient Calculator

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