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Hughes, R. D.

Publications and source records attributed to Hughes, R. D..

Design Procedure for the New 70-meter Antenna Subreflector Positioner

Design procedures are developed for determining Cassegrain type antenna subreflector positioner strength and displacements under wind and gravity loading conditions. The procedures are applied to the JPL 70-m antenna subreflector design, and the resulting design details are presented. The generalized analysis can be adapted to other antenna and subreflector-positioners. It is shown that the new design meets the strength and displacements criteria under worst case loading.

Hughes, R. D.

Subreflector Focusing Techniques Applied to New DSS-15 and DSS-45 34-meter Antennas

An improved technique to determine the subreflector translations required to properly focus a Cassegrainian antenna, under gravity loading, at a full range of elevation angles, is presented. This technique is applied to the 34-m antenna configuration installed at stations DSS-15 (Goldstone, California) and DSS-45 (Australia). The subreflector lateral and axial translations, to be stored into the antenna-control systems, are computed and tabulated. The relationships that govern the main parameters are also presented for future subreflector focusing analysis under wind and thermal loadings.

Hughes, R. D.

Antenna Radiation-Pattern Program

Effects of reflector deformations and feed characteristics computed. JPL Antenna Radiation Pattern computer program ANRAD, evaluates performance of radio-frequency antenna with paraboloidal main reflector by solving scalar far-field radiation pattern integral.

Hughes, R. D.

Thermal Analysis of the X-band 34-meter Antenna Feedcone

A thermal analysis was done to describe feedcone shell temperature profiles and induced thermal stresses in waveguide components. IMP-SS, a steady-state version of the thermal analysis computer program employing the implicit alterating-direction numerical technique documented in a previous report, was used to analyze the two dimensional regions of the feedcone. This portion of the analysis determined the free relative displacement of the feedcone for a worst-case thermal condition.

Hughes, R. D.

The Application of the Implicit Alternating-direction Numerical Technique to Thermal Analysis Involving Conduction and Convection

A computerized model was developed for analyzing the temperature distribution of a two dimensional body which is located at or near the soil surface and is partially exposed to solar radiation. The body may have one or more interior cavities containing air or another fluid. The methodology which evolved is also applicable to a general class of thermal analyses involving a body surrounded by a semi-infinite medium exposed to surface radiation energy. The theoretical analysis, numerical procedure, and a sample case are discussed.

Hughes, R. D.

Efficient computerized model for dynamic analysis of energy conversion systems

In searching for the optimum parameters that minimize the total life cycle cost of an energy conversion system, various combinations of components are examined and the resulting system performance and associated economics are studied. The systems performance and economics simulation computer program (SPECS) was developed to fill this need. The program simulates the fluid flow, thermal, and electrical characteristics of a system of components on a quasi-steady state basis for a variety of energy conversion systems. A unique approach is used in which the set of characteristic equations is solved by the Newton-Raphson technique. This approach eliminates the tedious iterative loops which are found in comparable programs such as TRNSYS or SOLTES-1. Several efficient features were also incorporated such as the centralized control and energy management scheme, and analogous treatment of energy flow in electrical and mechanical components, and the modeling of components of similar fundamental characteristics using generic subroutines. Initial tests indicate that this model can be used effectively with a relatively small number of time steps and low computer cost.

Hughes, R. D.

Potential availability of diesel waste heat at Echo Deep Space Station (DSS 12)

Energy consumption at the Goldstone Echo Deep Space Station (DSS 12) is predicted and quantified for a future station configuration which will involve implementation of proposed energy conservation modifications. Cogeneration by the utilization of diesel waste-heat to satisfy site heating and cooling requirements of the station is discussed. Scenarios involving expanded use of on-site diesel generators are presented.

Hughes, R. D.

A simplified solar cell array modelling program

As part of the energy conversion/self sufficiency efforts of DSN engineering, it was necessary to have a simplified computer model of a solar photovoltaic (PV) system. This article describes the analysis and simplifications employed in the development of a PV cell array computer model. The analysis of the incident solar radiation, steady state cell temperature and the current-voltage characteristics of a cell array are discussed. A sample cell array was modelled and the results are presented.

Hughes, R. D.

Reporting Capabilities and Management of the DSN Energy Data Base

The DSN Energy Data Base is a collection of computer files developed and maintained by DSN Engineering. The energy consumption data must be updated monthly and summarized and displayed in printed output as desired. The methods used to handle the data and perform these tasks are described.

Hughes, R. D.