Abstract: An apparatus and method for determining the thermal stability of fluids, particularly for testing the deposition characteristics of fuels, comprising a conduit system which connects in series; a test fluid reservoir having a movable piston capable of discharging the fluid, a heater section in which is mounted a heated tubular member, a time reactor of a sufficient volume to increase the residence time of the fluid therein, and a water displacement reservoir. The system also incorporates a filter located at an outlet of the heater section designed to trap deposits which may form due to the heating, and a similar filter located at an outlet of the time reactor designed to trap further deposits that may form with additional time. A differential pressure measuring device is connected across each of these filters to measure the pressure drop therethrough.

Abstract: An apparatus and method for determining the freezing point of substances, particularly liquids, that are likely to be used in environments that subject them to temperatures at or near their freezing points. The apparatus and method achieve a determination of the freezing point of the substance without the necessity of rigidly controlling the warming and cooling of the substance and without mistaking errant fluctuations in the thermal behavior of the substance for the freezing point. The apparatus includes a test sample cell that is cooled by direct contact with a rapidly expanding gas and a means for recording and analyzing temperature and time data for a test sample within the test sample cell. Means for controlling the test and displaying the information/data are also provided. The method utilizes a numerical analysis means to arrive at a freezing point value without the necessity of complex differentiating electronics or calculations.

Abstract: A short wavelength light beam such as the blue/green emission lines of an argon-ion laser, is projected through a narrow slit into a chamber onto a metal tube of the kind typically used to receive deposits in fuel testing. The spuriously reflected light is absorbed into the interior chamber wall. The beam spot on the tube is imaged by a short focal length lens onto a photodetector such as a photomultiplier tube. The radiation passing to the detector is filtered to block out all radiation except that having a wave length longer than the incident light. By this means, fluorescence from the deposits on such metal tubes, induced by the incident light beam, is quantified and is used as a proportional indication of the deposit thickness. The metal tube is simultaneously rotated and translated to scan the entire tube and thereby obtain a map of the tube deposits in order to establish a test rating for the fuel.

Abstract: An apparatus and method for determining the freezing point of substances, particularly liquids, that are likely to be used in environments that subject them to temperatures at or near their freezing points. The apparatus and method achieve a determination of the freezing point of the substance without the necessity of rigidly controlling the warming and cooling of the substance and without mistaking errant fluctuations in the thermal behavior of the substance for the freezing point. The apparatus includes a test sample cell that is cooled by direct contact with a rapidly expanding gas and a means for recording and analyzing temperature and time data for a test sample within the test sample cell. Means for controlling the test and displaying the information/data are also provided. The method utilizes a numerical analysis means to arrive at a freezing point value without the necessity of complex differentiating electronics or calculations.

Abstract: An apparatus for determining the thermal stability of fluids, particularly for testing the deposition characteristics of fuels, comprising a conduit system which connects in series; a reservoir to contain fresh fluid having within it a movable piston capable of discharging the fluid, a heater tube housing in which is mounted a heated tubular member, a time reactor housing of a sufficient volume to decrease the flow of the fluid therethrough, a spent fluid reservoir, a filter located at an outlet of the heater tube housing designed to trap deposits which may be formed due to the heating and remain suspended in the fluid, a similar filter located at an outlet of the time reactor housing designed to trap further deposits that may form with additional time, a differential pressure measuring device connected across each of these filters to measure the pressure drop therethrough, and a valved bypass around each of these filters.

Abstract: A piezoelectric device is used to determine the viscosity of a fluid. A piezoelectric driver is resiliently attached to a base that is isolated from vibrations. A piezoelectric receiver and a probe are resiliently attached to the piezoelectric driver so that the receiver and probe move in response to motion of the piezoelectric driver, and the piezoelectric receiver gives an electric signal out proportional to motion of the system. The entire system is set to operate near the resonant frequency for the receiver/probe. By applying an oscillating sine wave voltage such as 140 hertz, to the piezoelectric driver, and immersing the probe first in a fluid of known high viscosity, and then in a fluid of known low viscosity, calibrated outputs are obtained from the piezoelectric receiver. Next by exchanging a fluid of unknown viscosity for the known fluids, a third output is obtained that represents the unknown viscosity.

Abstract: An oven for heating a distillable material in a preselected gas atmosphere. The oven comprises an inner heating chamber adapted to receive a spherical gravity lid, the heating chamber being connected to and in communication with a gas exhaust tube having a condensate trap at the termination thereof. The inner heating chamber is also in communication with and surrounded by an outer gas flow chamber, the outer gas flow chamber having a plurality of heater elements therein. The gas exhaust tube is surrounded by an ante chamber which is in communication with the outer chamber. The heater elements are continuously monitored by a programmable controller and a thermocouple in communication therewith. During oven operation, a purge gas is introduced to the ante chamber and flows therefrom into the outer gas flow chamber around the heater elements and into the top of the inner heating chamber.

Abstract: A piezoelectric device is used to determine a ratio of a second weight with an original weight where the second weight is less than the original weight. A piezoelectric driver is resiliently attached to a base that is isolated from vibrations. A piezoelectric receiver and a reed are resiliently attached to the piezoelectric driver so that (1) the read is moved in response to motion of the piezoelectric driver, and (2) the piezoelectric receiver gives an electric signal out proportional to motion of the system. The entire system is set to operate on the leading edge of the resonant frequency for the system. By applying an oscillating sine wave voltage, such as 140 hertz, to the piezoelectric driver, and by applying an unknown mass to the tip of the reed, a first output is obtained from the piezoelectric receiver which represents the original weight. Next by removing part of the mass by any convenient means, such as heat, a second output is obtained that represents the second weight.

Abstract: An oven for heating a distillable material in a preselected gas atmosphere. The oven comprises an inner heating chamber adapted to receive a spherical gravity lid, the heating chamber being connected to and in communication with a gas exhaust tube having a condensate trap at the termination thereof. The inner heating chamber is also in communication with and surrounded by an outer gas flow chamber, the outer gas flow chamber having a plurality of heater elements therein. The gas exhaust tube is surrounded by an ante chamber which is in communication with the outer chamber. The heater elements are continuously monitored by a programmable controller and a thermocouple in communication therewith. During oven operation, a purge gas is introduced to the ante chamber and flows therefrom into the outer gas flow chamber around the heater elements and into the top of the inner heating chamber.