Physical Sciences

A system for storing and circulating a refrigerant liquid [R- 124 (chloro- tetrafluoroethane)] includes a reservoir and a subsystem that regulates the pressure of nitrogen gas in the head space of the reservoir. The purpose of the pressurization is to prevent cavitation in a pump...

Ellipsoidal reflectors have been proposed as collecting horns for ultrasonic leak detectors. Exploiting the classical focusing characteristics of ellipsoids, these reflectors would facilitate and enhance the detection of leaks in situations in which it is possible to bring leak-detecting...

A proposed infrared transmitting fiber-optic endoscope, which would partly resemble a visible-light fiber-optic endoscope, instrument could be used to perform thermal imaging in harsh environments and/or confined spaces in a variety of situations in aerospace, industrial, automotive, and medical settings.

Electrostatic dust- collection systems that comprise wire grids connected to lightweight, low-power high-voltage sources have been invented for preventing the accumulation of dust on surfaces. Intended originally for use in keeping spacecraft solar panels free of dust, these systems could also be used on...

The Hazardous Gas Detection System 2000 (HGDS 2000) is the latest in a series of instrumentation systems for detecting gases leaking from a space shuttle on a launch pad. The HGDS is a fully redundant system that includes analog and digital electronic control circuitry and a sub- system for...

Research at Langley Research Center has developed a special fiber- Bragg grating optical filter for use in aircraft or spaceborne differential absorption lidar (DIAL) systems for measuring water vapor in the atmosphere of the Earth. The filter is an optical fiber containing two Bragg...

A report discusses three designs of proposed low-power, zero-vibration coolers for infrared instruments planned to be flown aboard spacecraft to perform astrophysical observations far from Earth. The designs take advantage of the radiative precooling available in the projected deep-space operational...

A report presents an experimental study of time-resolved, temperature-dependent photoluminescence in InxGa1–x As/GaAs specimens containing In0.6Ga0.4As quantum dots (QDs) distributed at several different areal densities on a GaAs surface and capped with GaAs. The specimens were fabricated by...

This paper presents a study of area production in mixing layers undergoing transition to turbulence. These layers evolve from the mixing of two initially segregated counterflowing streams under supercritical conditions. The study may contribute to development of means to control area...

Missions to the surface of Mars pose unique thermal-control challenges to rover and lander systems. With diurnal temperature changes greater than 100 °C, the presence of a Mars atmosphere, and limited power for night-time heating, the thermal-control engineer is faced with a fundamental...

U-HUNTER (also called “UXOHUNTER”) is a computer program that affords knowledge-based real-time sensor- fusion and display capabilities for detecting buried objects and materials of interest. U-HUNTER is intended especially for inferring the presence of buried unexploded ordnance and...

Aircraft anti-icing systems of a proposed type would utilize static electric fields to reduce or eliminate the electrostatic forces that bond ice and water to metal surfaces. These would be lightweight, low-power-consumption, inexpensive systems that would be installed on the surfaces of...