Author: William H. Robbins
Publisher:
ISBN:
Category : Aerodynamics, Supersonic
Languages : en
Pages : 32
Book Description
A nuclear-rocket regenerative-cooling analysis was conducted over a range of reactor power of 46 to 1600 megawatts and is summarized herein. Although the propellant (hydrogen) is characterized by a large heat-sink capacity, an analysis of the local heat-flux capability of the coolant at the nozzle throat indicated that, for conventional values of system pressure drop, the cooling capability was inadequate to maintain a selected wall temperature of 1440 R. Several techniques for improving the cooling capability were discussed, for example, high pressure drop, high wall temperature, refractory wall coatings, thin highly conductive walls, and film cooling. In any specific design a combination of methods will probably be utilized to achieve successful cooling.
An Analysis of Nuclear-rocket Nozzle Cooling
Author: William H. Robbins
Publisher:
ISBN:
Category : Aerodynamics, Supersonic
Languages : en
Pages : 32
Book Description
A nuclear-rocket regenerative-cooling analysis was conducted over a range of reactor power of 46 to 1600 megawatts and is summarized herein. Although the propellant (hydrogen) is characterized by a large heat-sink capacity, an analysis of the local heat-flux capability of the coolant at the nozzle throat indicated that, for conventional values of system pressure drop, the cooling capability was inadequate to maintain a selected wall temperature of 1440 R. Several techniques for improving the cooling capability were discussed, for example, high pressure drop, high wall temperature, refractory wall coatings, thin highly conductive walls, and film cooling. In any specific design a combination of methods will probably be utilized to achieve successful cooling.
Publisher:
ISBN:
Category : Aerodynamics, Supersonic
Languages : en
Pages : 32
Book Description
A nuclear-rocket regenerative-cooling analysis was conducted over a range of reactor power of 46 to 1600 megawatts and is summarized herein. Although the propellant (hydrogen) is characterized by a large heat-sink capacity, an analysis of the local heat-flux capability of the coolant at the nozzle throat indicated that, for conventional values of system pressure drop, the cooling capability was inadequate to maintain a selected wall temperature of 1440 R. Several techniques for improving the cooling capability were discussed, for example, high pressure drop, high wall temperature, refractory wall coatings, thin highly conductive walls, and film cooling. In any specific design a combination of methods will probably be utilized to achieve successful cooling.
Analysis, Feasibility, and Wall-temperature Distribution of a Radiation-cooled Nuclear-rocket Nozzle
Author: William H. Robbins
Publisher:
ISBN:
Category : Fluid mechanics
Languages : en
Pages : 36
Book Description
Publisher:
ISBN:
Category : Fluid mechanics
Languages : en
Pages : 36
Book Description
A Design Study of a Regeneratively Cooled Nozzle for a Tungsten Water-moderated Nuclear Rocket System
Author: Richard L. Puthoff
Publisher:
ISBN:
Category : Liquid propellants
Languages : en
Pages : 44
Book Description
Publisher:
ISBN:
Category : Liquid propellants
Languages : en
Pages : 44
Book Description
Thermal Fatigue Analysis of a Cryogenically Cooled Rocket Nozzle
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 18
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 18
Book Description
An Analysis of Nuclear-rocket Nozzle Cooling
Author: William H. Robbins
Publisher:
ISBN:
Category : Aerodynamics, Supersonic
Languages : en
Pages : 28
Book Description
A nuclear-rocket regenerative-cooling analysis was conducted over a range of reactor power of 46 to 1600 megawatts and is summarized herein. Although the propellant (hydrogen) is characterized by a large heat-sink capacity, an analysis of the local heat-flux capability of the coolant at the nozzle throat indicated that, for conventional values of system pressure drop, the cooling capability was inadequate to maintain a selected wall temperature of 1440 R. Several techniques for improving the cooling capability were discussed, for example, high pressure drop, high wall temperature, refractory wall coatings, thin highly conductive walls, and film cooling. In any specific design a combination of methods will probably be utilized to achieve successful cooling.
Publisher:
ISBN:
Category : Aerodynamics, Supersonic
Languages : en
Pages : 28
Book Description
A nuclear-rocket regenerative-cooling analysis was conducted over a range of reactor power of 46 to 1600 megawatts and is summarized herein. Although the propellant (hydrogen) is characterized by a large heat-sink capacity, an analysis of the local heat-flux capability of the coolant at the nozzle throat indicated that, for conventional values of system pressure drop, the cooling capability was inadequate to maintain a selected wall temperature of 1440 R. Several techniques for improving the cooling capability were discussed, for example, high pressure drop, high wall temperature, refractory wall coatings, thin highly conductive walls, and film cooling. In any specific design a combination of methods will probably be utilized to achieve successful cooling.
Feasibility of Optimizing Nozzle Performance for Orbital-launch Nuclear Rockets
Author: John R. Jack
Publisher:
ISBN:
Category : Rockets (Aeronautics)
Languages : en
Pages : 36
Book Description
Publisher:
ISBN:
Category : Rockets (Aeronautics)
Languages : en
Pages : 36
Book Description
Analysis of Heat-transfer Effects in Rocket Nozzles Operating with Very High-temperature Hydrogen
Author: John R. Howell
Publisher:
ISBN:
Category : Energy transfer
Languages : en
Pages : 44
Book Description
An analytical technique suitable for & the solution of complex energy transfer problems involving coupled radiant and convective energy transfer is developed. Solutions for the coupled axial wall energy flax distribution in rocket nozzles using hydrogen as a propellant are presented. Flow rates and temperatures studied are near those forecast for gaseous-core nuclear-propulsion systems. Parameters varied are nozzle shape, inlet propellant temperature, mean reactor cavity temperature, and nozzle wall temperature level. The effects of variation of the propellant radiation absorption coefficient with pressure, temperature, and wavelength are presented, and real property variations are used where they appear to be significant. Comparison is made to a simplified, coupled solution using a modified second-order one-dimensional diffusion equation for the radiative transfer. At the temperature levels assumed, radiative transfer may account for a greater portion of the total energy transfer over important portions of the nozzle, and its effects cannot, therefore, be neglected. Extreme energy flaxes (near 3XlO to the 8 Btu/(hr)(sq ft)) are observed for certain cases, and this implies that new nozzle cooling techniques must be developed.
Publisher:
ISBN:
Category : Energy transfer
Languages : en
Pages : 44
Book Description
An analytical technique suitable for & the solution of complex energy transfer problems involving coupled radiant and convective energy transfer is developed. Solutions for the coupled axial wall energy flax distribution in rocket nozzles using hydrogen as a propellant are presented. Flow rates and temperatures studied are near those forecast for gaseous-core nuclear-propulsion systems. Parameters varied are nozzle shape, inlet propellant temperature, mean reactor cavity temperature, and nozzle wall temperature level. The effects of variation of the propellant radiation absorption coefficient with pressure, temperature, and wavelength are presented, and real property variations are used where they appear to be significant. Comparison is made to a simplified, coupled solution using a modified second-order one-dimensional diffusion equation for the radiative transfer. At the temperature levels assumed, radiative transfer may account for a greater portion of the total energy transfer over important portions of the nozzle, and its effects cannot, therefore, be neglected. Extreme energy flaxes (near 3XlO to the 8 Btu/(hr)(sq ft)) are observed for certain cases, and this implies that new nozzle cooling techniques must be developed.
Digital Codes for Design and Evaluation of Convectively Cooled Rocket Nozzle with Application to Nuclear-type Rocket
Author: John E. Rohde
Publisher:
ISBN:
Category : Rockets (Aeronautics)
Languages : en
Pages : 98
Book Description
Publisher:
ISBN:
Category : Rockets (Aeronautics)
Languages : en
Pages : 98
Book Description
Engine Cycle Analysis for a Particle Bed Reactor Nuclear Rocket
Author: David E. Suzuki
Publisher:
ISBN:
Category :
Languages : en
Pages : 62
Book Description
This report addresses three candidate engine cycles for a particle bed nuclear rocket; bleed cycle with uncooled carbon - carbon composite nozzle; bleed cycle with regeneratively cooled Aluminum nozzle; expander cycle with regeneratively cooled Aluminum nozzle. The analysis was performed using the SALT System Analysis Language Translator code with the following amendments; particle bed reactor was modeled as a simple heater; a regeneratively cooled nozzle model was added which includes the heating of the coolant due to hot exhaust gases and nuclear heating of nozzle. The conclusion of the analysis were the topping cycle should be pursued for Mars missions and the bleed cycle should be pursued for OTV (Orbital Transfer Vehicle) missions. This study indicates that a regeneratively cooled aluminum nozzle can be sufficiently cooled to allow its use with a PBR rocket engine. This result is based on nozzle heating due to hot exhaust gases at a maximum chamber temperature and nuclear heating effects. The highest temperatures occur at the nozzle throat, where a composite or alloy coating could protect the aluminum. Further investigation of nozzle cooling should include modeling the nozzle with more nodes, and including more accurate dimensions for the nozzle wall thicknesses and coolant flow passages. The study also indicates that an expander cycle with a cooled aluminum nozzle can operate with a high pressure PBR at realistic TPA efficiencies. Further investigation should include the improvements to the regeneratively cooled nozzle model and more accurate performance maps for the TPA components.
Publisher:
ISBN:
Category :
Languages : en
Pages : 62
Book Description
This report addresses three candidate engine cycles for a particle bed nuclear rocket; bleed cycle with uncooled carbon - carbon composite nozzle; bleed cycle with regeneratively cooled Aluminum nozzle; expander cycle with regeneratively cooled Aluminum nozzle. The analysis was performed using the SALT System Analysis Language Translator code with the following amendments; particle bed reactor was modeled as a simple heater; a regeneratively cooled nozzle model was added which includes the heating of the coolant due to hot exhaust gases and nuclear heating of nozzle. The conclusion of the analysis were the topping cycle should be pursued for Mars missions and the bleed cycle should be pursued for OTV (Orbital Transfer Vehicle) missions. This study indicates that a regeneratively cooled aluminum nozzle can be sufficiently cooled to allow its use with a PBR rocket engine. This result is based on nozzle heating due to hot exhaust gases at a maximum chamber temperature and nuclear heating effects. The highest temperatures occur at the nozzle throat, where a composite or alloy coating could protect the aluminum. Further investigation of nozzle cooling should include modeling the nozzle with more nodes, and including more accurate dimensions for the nozzle wall thicknesses and coolant flow passages. The study also indicates that an expander cycle with a cooled aluminum nozzle can operate with a high pressure PBR at realistic TPA efficiencies. Further investigation should include the improvements to the regeneratively cooled nozzle model and more accurate performance maps for the TPA components.
Nuclear Thermal Rocket Nozzle Testing and Evaluation Program
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 12
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 12
Book Description