When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Liquid hydrogen - Wikipedia

    en.wikipedia.org/wiki/Liquid_hydrogen

    The density of liquid hydrogen is only 70.85 kg/m 3 (at 20 K), a relative density of just 0.07. Although the specific energy is more than twice that of other fuels, this gives it a remarkably low volumetric energy density, many fold lower.

  3. Energy density Extended Reference Table - Wikipedia

    en.wikipedia.org/wiki/Energy_density_Extended...

    1.80 [16] 1.26: battery, Fluoride-ion [citation needed] 1.7: 2.8: battery, Hydrogen closed cycle H fuel cell [17] 1.62: Hydrazine decomposition (as monopropellant) 1.6: 1.6: Ammonium nitrate decomposition (as monopropellant) 1.4: 2.5: Thermal Energy Capacity of Molten Salt: 1 [citation needed] 98% [18] Molecular spring approximate [citation ...

  4. Densities of the elements (data page) - Wikipedia

    en.wikipedia.org/wiki/Densities_of_the_elements...

    — "Values ranging from 21.3 to 21.5 gm/cm 3 at 20 °C have been reported for the density of annealed platinum; the best value being about 21.45 gm/cm 3 at 20 °C." 21.46 g/cm 3 — Rose, T. Kirke. The Precious Metals, Comprising Gold, Silver and Platinum .

  5. Hydrogen storage - Wikipedia

    en.wikipedia.org/wiki/Hydrogen_storage

    Chemical storage could offer high storage performance due to the high storage densities. For example, supercritical hydrogen at 30 °C and 500 bar only has a density of 15.0 mol/L while methanol has a hydrogen density of 49.5 mol H 2 /L methanol and saturated dimethyl ether at 30 °C and 7 bar has a density of 42.1 mol H 2 /L dimethyl ether.

  6. Kilogram per cubic metre - Wikipedia

    en.wikipedia.org/wiki/Kilogram_per_cubic_metre

    The kilogram per cubic metre (symbol: kg·m −3, or kg/m 3) is the unit of density in the International System of Units (SI). It is defined by dividing the SI unit of mass, the kilogram, by the SI unit of volume, the cubic metre. [1]

  7. Prandtl number - Wikipedia

    en.wikipedia.org/wiki/Prandtl_number

    0.065 for molten lithium at 975 K [1] around 0.16–0.7 for mixtures of noble gases or noble gases with hydrogen; 0.63 for oxygen [1] around 0.71 for air and many other gases; 1.38 for gaseous ammonia [1] between 4 and 5 for R-12 refrigerant; around 7.56 for water (At 18 °C) 13.4 and 7.2 for seawater (At 0 °C and 20 °C respectively) 50 for n ...

  8. Dimensionless numbers in fluid mechanics - Wikipedia

    en.wikipedia.org/wiki/Dimensionless_numbers_in...

    Dimensionless numbers (or characteristic numbers) have an important role in analyzing the behavior of fluids and their flow as well as in other transport phenomena. [1] They include the Reynolds and the Mach numbers, which describe as ratios the relative magnitude of fluid and physical system characteristics, such as density, viscosity, speed of sound, and flow speed.

  9. Lifting gas - Wikipedia

    en.wikipedia.org/wiki/Lifting_gas

    The amount of mass that can be lifted by hydrogen in air per unit volume at sea level, equal to the density difference between hydrogen and air, is: (1.292 - 0.090) kg/m 3 = 1.202 kg/m 3. and the buoyant force for one m 3 of hydrogen in air at sea level is: 1 m 3 × 1.202 kg/m 3 × 9.8 N/kg= 11.8 N