摘要:

Heat transfer coefficients have been determined in a fluidized solids bed under a wide variety of conditions. The variables studied were particle size, bulk density under nonfluidized conditions, particle shape, and air velocity. Simple correlations have been established predicting the value ofhin the air flow range investigated. An equation predicting the minimum fluidizing velocity has also been derived.

ISSN:1923-4287    

DOI:10.1139/cjr50f-025

出版商:NRC Research Press    

年代:1950

数据来源: NRC

摘要:

Experiments are described which demonstrate that benzene becomes a knocking fuel when used in a spark ignition Otto cycle engine if operating conditions are such that the vapor–air mixture becomes impregnated with finely divided carbon. The carbon was obtained on the impingement of the flame of burning benzene on relatively cool surfaces in the combustion chamber and by the burning of liquid drops dispersed in a combustible vapor–air mixture. The droplets were obtained by wet carburation even when the over-all mixture was weak; the engine being run with low temperature coolant, low temperature air supply, and with the carburetor attached directly to the engine head.

ISSN:1923-4287    

DOI:10.1139/cjr50f-026

出版商:NRC Research Press    

年代:1950

数据来源: NRC

摘要:

A projector unit is described in which the film advance sprocket is driven by a reversible motor and the glass pressure plate is automatically released while the film is being moved. The film spools accommodate 100 ft. of 35 mm. film and take up slack in both directions. Several units may be used simultaneously for correlation of multiple records.

ISSN:1923-4287    

DOI:10.1139/cjr50f-027

出版商:NRC Research Press    

年代:1950

数据来源: NRC

摘要:

An electromechanical instrument has been developed, which adds, subtracts, multiplies, or divides the ordinates of two curves in Cartesian co-ordinates, plotting the resulting locus. This uses the principle of the Wheatstone bridge, and is semiautomatic; the curves are followed manually, but a phase-sensitive servo system keeps the bridge in balance. Attachments are provided for determining the area under the resulting curve, and also for the performance of certain logarithmic operations of interest in photometry. In the ordinary use of the computer, the accuracy is about 0.3% of full scale or better.

ISSN:1923-4287    

DOI:10.1139/cjr50f-028

出版商:NRC Research Press    

年代:1950

数据来源: NRC

摘要:

Measurement of air flow with variable orifice type flowmeters in laboratory experiments revealed discrepancies that could not be explained as errors arising from faulty calibration, leaks in the system, or failure to reduce readings to standard conditions of temperature and pressure. They were found to arise because of the occurrence of rapid pulsations in the air flow. A theoretical analysis of the effect showed that these instruments indicate root mean square rather than average flow rates. The results of experiments designed to test the theory were in reasonable agreement with the predicted values. It was found that errors arising from the occurrence of pulsations could be minimized by insertion of a suitable smoothing device between the pump and flowmeter. For example, an orifice with a pressure drop of 40 cm. of water reduced the flowmeter error to 5% of the true flow rate.

ISSN:1923-4287    

DOI:10.1139/cjr50f-029

出版商:NRC Research Press    

年代:1950

数据来源: NRC