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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
NASA NTRS1968

Processing and manufacture of composite propellants

This paper is a chemical engineering unit processing treatment of the steps involved in the manufacture of solid propellant motors. The author treats the major processes of raw material preparation, mixing, casting and curing by describing equipment, the processing, steps and some engineering considerations associated therewith. The three simultaneous processes occurring within the solid propellant nixing, namely, homogenization, wetting and curing, are discussed in more detail, briefly touching on control of these reactions and the engineering trade-offs among them.

J F Tormey↗
NASA NTRS1970

Liquid rocket technology for the ch. e.

Liquid rocket technology for chemical engineers, discussing propellant tanks, lines and valves, tank pressurization, turbopumps and combustion chamber problems

Priem, R. J.↗
NASA NTRS1975

Chemical research projects office functions accomplishments programs

Basic and applied research in the fields of polymer chemistry, polymeric composites, chemical engineering, and biophysical chemistry is summarized. Emphasis is placed on fire safety and human survivability as they relate to commercial and military aircraft, high-rise buildings, mines and rapid transit transportation. Materials systems and other fire control systems developed for aerospace applications and applied to national domestic needs are described along with bench-scale and full-scale tests conducted to demonstrate the improvements in performance obtained through the utilization of these materials and fire control measures.

Heimbuch, A. H.↗
NASA NTRS1976

Simulation of fluidized bed combustors. I - Combustion efficiency and temperature profile

A chemical engineering analysis is made of fluidized-bed combustor (FBC) performance, with FBC models developed to aid estimation of combustion efficiency and axial temperature profiles. The FBC is intended for combustion of pulverized coal and a pressurized FBC version is intended for firing gas turbines by burning coal. Transport phenomena are analyzed at length: circulation, mixing models, drifting, bubble wake lift, heat transfer, division of the FB reactor into idealized mixing cells. Some disadvantages of a coal FBC are pointed out: erosion of immersed heat-transfer tubing, complex feed systems, carryover of unburned coal particles, high particulate emission in off-streams. The low-temperature bed (800-950 C) contains limestone, and flue-gas-entrained SO2 and NOx can be kept within acceptable limits.

Horio, M.↗
NASA NTRS1977

Cloud physics laboratory project science and applications working group

The conditions of the expansion chamber under zero gravity environment were simulated. The following three branches of fluid mechanics simulation under low gravity environment were accomplished: (1) oscillation of the water droplet which characterizes the nuclear oscillation in nuclear physics, bubble oscillation of two phase flow in chemical engineering, and water drop oscillation in meteorology; (2) rotation of the droplet which characterizes nuclear fission in nuclear physics, formation of binary stars and rotating stars in astrophysics, and breakup of the water droplet in meteorology; and (3) collision and coalescence of the water droplets which characterizes nuclear fusion in nuclear physics and processes of rain formation in meteorology.

Hung, R. J.↗
NASA NTRS1978

Process feasibility study in support of silicon material task 1

Initial results for gas thermal conductivity of silicon tetrafluoride and trichlorosilane are reported in respective temperature ranges of 25 to 400 C and 50 to 400 C. For chemical engineering analyses, the preliminary process design for the original silane process of Union Carbide was completed for Cases A and B, Regular and Minimum Process Storage. Included are raw material usage, utility requirements, major process equipment lists, and production labor requirements. Because of the large differences in surge tankage between major unit operations the fixed capital investment varied from $19,094,000 to $11,138,000 for Cases A and B, respectively. For the silane process the original flowsheet was revised for a more optimum arrangement of major equipment, raw materials and operating conditions. The initial issue of the revised flowsheet (Case C) for the silane process indicated favorable cost benefits over the original scheme.

Fang, C. S.↗
NASA NTRS1979

Chemical processing of lunar materials

The paper highlights recent work on the general problem of processing lunar materials. The discussion covers lunar source materials, refined products, motivations for using lunar materials, and general considerations for a lunar or space processing plant. Attention is given to chemical processing through various techniques, including electrolysis of molten silicates, carbothermic/silicothermic reduction, carbo-chlorination process, NaOH basic-leach process, and HF acid-leach process. Several options for chemical processing of lunar materials are well within the state of the art of applied chemistry and chemical engineering to begin development based on the extensive knowledge of lunar materials.

Criswell, D. R.↗
NASA NTRS1980

An equation of state for liquids

Closed expression for volume as function of pressure and temperature has been verified for over 250 liquids. Equation can assist chemical engineers, soild-state researchers, and others with interest in thermodynamic behavior of liquids.

Fedors, R. F.↗
NASA NTRS1980

Low-thrust chemical propulsion

Results from investigations leading to the definition of low thrust chemical engine concepts are described. From the thrust chamber cooling analyses, regenerative/radiation-cooled LO2/H2 thrust chambers offered the largest thrust and chamber pressure operational envelope primarily due to the superior cooling capability of hydrogen and its low critical pressure. Regenerative/radiation-cooled LO2/CH4 offered the next largest operational envelope. The maximum chamber pressure for film/radiation-cooling was significantly lower than for regenerative/radiation-cooling. As in regeneration-cooling, LO2/H2 thrust chambers achieved the highest maximum chamber pressure, LO2/CH4 film/radiation-cooling was found not feasible and LO2/RP-1 film/radiation-cooling was extremely limited. In the engine cycle/configuration evaluation, the engine cycle matrix was defined through the incorporation of the heat transfer results. Engine cycle limits were established with the fuel-cell power cycle achieving the highest chamber pressure; however, the fuel cell system weights were excessive. The staged combustion cycle achieved the next highest chamber pressure but the preburner operational feasibility was in question.

Shoji, J. M.↗
NASA NTRS1979

Low cost processes for silicon

The paper describes the multiple process development of low cost processes for manufacture of silicon. A support program includes subtasks for the modeling of reactions and reactors, chemical engineering and solid-state physics studies, and development of impurity concentration measurement procedures. The preliminary economic analyses indicate total product costs ranging from $5.00 to $8.73/kg based on 1000 MT/yr plants. In the studies of impurity effects, a model which considers that degradations of solar cell performance by impurities are primarily due to decreases in base diffusion length was constructed from experimental data.

Lutwack, R.↗
NASA NTRS1981

Silicon production process evaluations

The chemical engineering analysis of the preliminary process design of a process for producing solar cell grade silicon from dichlorosilane is presented. A plant to produce 1,000 MT/yr of silicon is analyzed. Progress and status for the plant design are reported for the primary activities of base case conditions (60 percent), reaction chemistry (50 percent), process flow diagram (35 percent), energy balance (10 percent), property data (10 percent) and equipment design (5 percent).

Source record↗
NASA NTRS1982

Silicon production process evaluations

Chemical engineering analysis was continued for the HSC process (Hemlock Semiconductor Corporation) in which solar cell silicon is produced in a 1,000 MT/yr plant. Progress and status are reported for the primary engineering activities involved in the preliminary process engineering design of the plant base case conditions (96%), reaction chemistry (96%), process flow diagram (85%), material balance (85%), energy balance (60%), property data (60%), equipment design (40%), major equipment list (30%) and labor requirements (10%). Engineering design of the second distillation column (D-02, TCS column) in the process was completed. The design is based on a 97% recovery of the light key (TCS, trichlorosilane) in the distillate and a 97% recovery of the heavy key (TET, silicon tetrachloride) in the bottoms. At a reflux ratio of 2, the specified recovery of TCS and TET is achieved with 20 trays (equilibrium stages, N=20). Respective feed tray locations are 9, 12 and 15 (NF sub 1 = 9, NF sub 2 = 12,, and NF sub 3 = 15). A total condenser is used for the distillation which is conducted at a pressure of 90 psia.

Source record↗
NASA NTRS1988

Microgravity nucleation and particle coagulation experiments support

Researchers at NASA Goddard Space Flight Center have embarked on a program to study the formation and growth of cosmic grains. This includes experiments on the homogeneous nucleation of refractory vapors of materials such as magnesium, lead, tin, and silicon oxides. As part of this program, the Chemical Engineering Department of the University of Virginia has undertaken to develop a math model for these experiments, to assist in the design and construction of the apparatus, and to analyze the data once the experiments have begun. Status Reports 1 and 2 addressed the design of the apparatus and the development of math models for temperature and concentration fields. The bulk of this report discusses the continued refinement of these models, and the assembly and testing of the nucleation chamber along with its ancillary equipment, which began in the spring of 1988.

Lilleleht, L. U.↗
NASA NTRS1991

A mathematical model of the maximum power density attainable in an alkaline hydrogen/oxygen fuel cell

A mathematical model of a hydrogen/oxygen alkaline fuel cell is presented that can be used to predict the polarization behavior under various power loads. The major limitations to achieving high power densities are indicated and methods to increase the maximum attainable power density are suggested. The alkaline fuel cell model describes the phenomena occurring in the solid, liquid, and gaseous phases of the anode, separator, and cathode regions based on porous electrode theory applied to three phases. Fundamental equations of chemical engineering that describe conservation of mass and charge, species transport, and kinetic phenomena are used to develop the model by treating all phases as a homogeneous continuum.

Kimble, Michael C.↗
NASA NTRS1990

Human exploration - Moon/Mars mission

The Space Eploration Initiative launched by the Bush Administration in May, 1990, will intensively explore alternative mission architectures involving the use of the moon as a staging post for manned exploration of Mars. The advanced technologies to be analyzed by the 'Pathfinder' program for prospective use in the alternative missions thus far defined encompass aerobraking, space-based chemical engines, cryogenic fluid systems, space nuclear power, nuclear-thermal and nuclear-electric propulsion, high-rate communications, and planetary photonics. Extensive use of robotics is anticipated in both the lunar and Martian components of the missions being studied.

O'Handley, Douglas A.↗
NASA NTRS1992

Advanced Manufacturing and Value-added Products from US Agriculture

An objective of the US Department of Agriculture (USDA) Agriculture Research Service (ARS) is to develop technology leading to a broad portfolio of value-added marketable products. Modern scientific disciplines such as chemical engineering are brought into play to develop processes for converting bulk commodities into high-margin products. To accomplish this, the extremely sophisticated processing devices which form the basis of modern biotechnology, namely, genes and enzymes, can be tailored to perform the required functions. The USDA/ARS is a leader in the development of intelligent processing equipment (IPE) for agriculture in the broadest sense. Applications of IPE are found in the production, processing, grading, and marketing aspects of agriculture. Various biotechnology applications of IPE are discussed.

Villet, Ruxton H.↗
NASA NTRS1993

Advanced expander test bed program

The Advanced Expander Test Bed (AETB) is a key element in NASA's Space Chemical Engine Technology Program for development and demonstration of expander cycle oxygen/hydrogen engine and advanced component technologies applicable to space engines as well as launch vehicle upper stage engines. The AETB will be used to validate the high-pressure expander cycle concept, investigate system interactions, and conduct investigations of advanced mission focused components and new health monitoring techniques in an engine system environment. The split expander cycle AETB will operate at combustion chamber pressures up to 1200 psia with propellant flow rates equivalent to 20,000 lbf vacuum thrust. Contract work began 27 Apr. 1990. During 1992, a major milestone was achieved with the review of the final design of the oxidizer turbopump in Sep. 1992.

Riccardi, D. P.↗
NASA NTRS1991

Lunar mission design using Nuclear Thermal Rockets

The NERVA-class Nuclear Thermal Rocket (NTR), with performance nearly double that of advanced chemical engines, has long been considered an enabling technology for human missions to Mars. NTR engines address the demanding trip time and payload delivery needs of both cargo-only and piloted flights. But NTR can also reduce the Earth launch requirements for manned lunar missions. First use of NTR for the Moon would be less demanding and would provide a test-bed for early operations experience with this powerful technology. Study of application and design options indicates that NTR propulsion can be integrated with the Space Exploration Initiative scenarios to deliver performance gains while managing controlled, long-term disposal of spent reactors to highly stable orbits.

Stancati, Michael L.↗