Expert in Thermal and Fluid Systems Engineering Design, Analysis, Sizing, and Project Management
Expert notes that the spacecraft thermal radiator is a heat exchanger that transfers the waste heat from the spacecraft coolant fluid to the radiation temperature environment of space. Thermal radiation is the dominant mode of heat transfer in a spacecraft radiator but forced convection inside the coolant fluid flow tubes and conduction through the panels are also important. Radiation heat flux values are relatively low for the typical temperatures of the waste heat and thus large areas are normally required to reject the heat. This imposes a significant weight penalty to the spacecraft and thus, optimization of the design is a high priority. The panels are typically coated with materials with high thermal radiation emissivity (i.e. emits large amount of energy in the infrared wave length) and low solar absorptivity (i.e. a good reflector of solar energy). Since the thermal radiation environments are cyclical in earth orbit, going from warmer on the sun side of the orbit and usually colder on the dark side, transient heat transfer is important in sizing a space radiator.
Expert led the program to design, develop, qualify and produce the International Space Station Heat Rejection Subsystem Radiator Assembly. Because of the developing nature of the International Space Station, the Radiator Assembly thermal design was redefined several times as the Space Station and interfacing systems configurations were changed by NASA and the prime contractors. Designs considered for the International Space Station as the Space Station configuration and assembly philosophy developed included:
1) Body mounted heat pipe radiators and pumped liquid radiators attached to the outside of the modules.
2) Large radiator array assembled in orbit from many (70) smaller elements, each one foot wide by 50 feet long and each containing two high capacity heat pipes. The assembled panels interfaced the two-phase condensing ammonia coolant fluid with a contact conductance heat exchanger.
3) The final design and the one now in orbit for International Space Station consists of six radiator assemblies, each stowed for launch in a volume of 9 feet by 12 feet by 2.7 feet and deployed in orbit to provide radiation heat transfer area of 1500 square feet and 11.7 kW of heat rejection (70 kW for six units). Heat is transported within the radiator system by circulated liquid ammonia. Many complex issues were addressed during the development of the final design, including whether to utilize a single phase or two-phase ammonia heat transport system, design of the system to continue operation at low heat load conditions with environments below ammonia freezing temperatures, the design of the system for deploying radiator panels, and how to best protect the fluid passages from micrometeoroid and space debris impacts.
Expert may consult nationally and internationally, and is also local to the following cities: Dallas, Texas - Fort Worth, Texas - Arlington, Texas - Plano, Texas - Garland, Texas - Irving, Texas - Grand Prairie, Texas - Mesquite, Texas - Waco, Texas - Carrollton, Texas
|Year: 1964||Degree: M.S.||Subject: Mechanical Engineering||Institution: University of Southern California|
|Year: 1961||Degree: B.S.||Subject: Mechanical Engineering||Institution: Oklahoma State University|
|Years: 2000 to 2005||Employer: Oren Engineering Consulting (Self Employed)||Title: Thermal Engineering Consultant||Department:||Responsibilities: Expert is the owner and principal consultant specializing in thermal and fluid systems engineering.|
|Years: 1964 to 2000||Employer: Lockheed Martin||Title: Program Manager||Department: Missiles and Fire Controls||Responsibilities: Expert had the following responsibilities during employment with Lockheed Martin (formerly Loral and LTV Aerospace):
Program Manager for the International Space Station Heat Rejection Subsystem (HRS) Radiators - October 1989 through September 2000. Directed all aspects of the HRS Radiator program including design, development, qualification, fabrication, cost/schedule and delivery. Six radiator assemblies delivered each weighing 2470 lbs with 1500 ft2 of radiation area when deployed in space.
Technical Project Manager for the International Space Station Heat Rejection conceptual and preliminary designs - September 1983 through October 1989. Performed design trade studies to optimize heat rejection system concepts in concert with the changing Prime Contractor Space Station concepts. Considered the latest technologies including two-phase heat transport systems, heat pipes, thermal storage, and capillary pumped loops. Prepared proposals for flight Heat Rejection System deployed radiator program. (Contract awarded.)
Technical Supervisor of a thermal control and fluid systems advanced design group - February 1976 through September 1983. Directed the development of new thermal control technologies, advanced thermal control system designs for large manned spacecraft, and spacecraft refrigeration systems designs including thermoelectric devices.
Assistant Project Engineer for the Space Shuttle Heat Rejection System - January 1975 through January 1976. Directed the development of fluid temperature control system and radiator system Freon coolant flow design. Managed fluid system component suppliers.
Thermal Engineer - August 1964 through December 1974. Performed mission simulation thermal modeling and analyses for the Space Shuttle Orbiter Radiator System, the Shuttle Freon Coolant Loop, the Apollo Fuel Cell System and Radiator and many other programs.
|Years: 1961 to 1964||Employer: Rockwell International Corporation (Now Boeing)||Title: Research Engineer||Department: Rocketdyne Division||Responsibilities: Expert's responsibilities at Rocketdyne consisted of development and testing of design modifications for centrifugal liquid propellant feed turbopumps for the Atlas and Saturn Rocket Engines.|
|Associations / Societies|
|Expert has now or has had the following professional association memberships: member of ASME for 24 years; member of SAE SC9 Thermal Control Committee for past 10 years; and, he served a three year term (maximum duration) on the AIAA Thermophysics Committee.|
|Licenses / Certifications|
|He is a Registered Professional Engineer in the State of Texas.|
|Awards / Recognition|
| Expert has received:
Defense Contractor Management Commander Outstanding Achievement Award (September 2000) for work on the International Space Station Heat Rejection Subsystem Contract
Loral Vought Systems Corp. Directors Appreciation Award (October 1993) for "Can Do" Attitude in conducting the Space Station Contract
NASA Certificate of Recognition for "Passive Self-Reprime Design for Arterial Heat Pipe", April 1991
LTV Missiles and Electronics Group Quarterly Outstanding Achievement Award for 1st Quarter 0f 1990
NASA Certificate of Recognition for "Round High Capacity Heat Pipe Evaporator Section", August 1987
NASA Apollo Achievement Award for Contributions to Apollo 11 successful mission (1969)
|Publications and Patents Summary|
|He has published over 16 NASA and Air Force contractor reports and six technical papers in the field of spacecraft thermal control.|
|Training / Seminars|
|Expert participated in teaching a continuing education course on Aerospace Thermal Control at Lockheed Martin through Mountain View Community College for two separate semesters. Expert taught half the course in each of the two semesters, covering (1) Spacecraft Thermal Control and (2) Heat Pipe Theory. (The other half of the course, Aerodynamic Heating and Thermal Stress Analysis, covered under the same course, was taught by another individual for both semesters.)|
|He was involved for many years selecting vendors for components and subsystems for thermal control systems. Some of the components for which vendors were selected were thermal control valves, heat pipes, heat exchangers, gearboxes, stepping motors, DC motors, and basic materials such as aluminum honeycomb and aluminum sheet materials, structural extrusions, and thermal control coatings.|
|Expert was involved in marketing and sales of thermal control systems to potential government and prime contractors for many years. His efforts were directly responsible for the award of the International Space Station heat rejection system radiators to Lockheed Martin in 1989.|
|Other Relevant Experience|
|He developed several general computer programs for thermal analysis of combined thermal and fluid systems, and he developed a computer program to automatically adjust the elements of a thermal model based upon sparse test data.|