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PROJECT CHARGE: 1706 PROJECT TITLE: TOBACCO PHYSICS PROJECT LEADER: D. B. Losee I r Ii L PERIOD COVERER: July 1- 31, 1981 DATE OF REPORT: July 31, 1981 APPLICATION OF TECHNOLOGY (1,2,3,4,5,6) Equations to simulate'beat.transfer to tobacco while in the expansion tower are being developed. Equations for the temperature of the gas and tobacco have been written and converted to finite difference form. The heat transfer coeffi- cients will be estimated from velocities based on Dr. J. Washington's calculated tower-particle-velocities. Research coatinues on the measurement of heat transferred from a smoldering cigarette. A calculation of the heat generated as the cigarette smolders indi- cates that only approximately 2% of the total heat is sensed by the metal band in close contact with the cigarette. Despite this small amount of detectable heat, differences can be found between experimental cigarettes. These cigarettes, pro- vided by Development, differed in tobacco type, cigarette parameters and cigarette paper treatment. In addition, from a study of ten selected commercial cigarettes preliminary results suggest that one can infer ignition propensities from the measured heat transferred. Work continues on the refinement of the measurement technique. Correlations that exist between igaition propensities and the heat transferred from the smoldering cigarette will be pursued. The mason-jar-heat-treatment experiments have been completed. Bright tobacco samples heated in sealed mason jars at 94°C for selected times over a .48 hour period are now equilibrating in the humidity chamber. Evolved gases were collected on each sample. The tobacco sample from each time period will be distributed for OV, CV, SV and reducing sugar. determination as well as'to Dr. R. Morgan for Ca2+ extraction rate data. Samples for the seven component blend analysis were prepared. Data collection will begin after repair of the spectrophotometer. MODELS FOR COMBUSTION/PYROLYSIS (3,4,7,8,5) Data collection for the mass balance study has been completed. The data set now consists of the gases not captured by the TPM pads in the evolved TPM tube

Monthly Progress Report D. B. Losee (1706) July 31, 1981 furnace experiment, the TPM weights and the tobacco residue weights; all collected as a function of 25°C temperature intervals at a heating rate of 1°C/min. and a flow rate of 60cc/min. This study will provide a check on the quality of our current accounting of the evolving mass as a function of temperature. A comparison of this mass breakdown with published whole cigarette smoke should provide a handle on how accurate a model our pyrolysis studies.are for cigarettes. A study_of the evolution.of.nicotine as a function of temperature fraction and flow rate during tube furnace;pyrolysis of.bright.tobacco-has been completed. In contrast with pyrolysis TPM evolution, nicotine evolution is flow rate inde- pendent with a peak evolution occurring at 200°C. In earlier~studies the amouat of TPM evolved below.325°C was flow independent while above this temperature the TPM was flow dependent. Agreement with earlier-studies on much larger samples from a much larger tube furnace indicate that wide range of sample sizes may be pyrolyzed under similar tube furnace.conditions without effecting the temperature profiles of major pyrolytic products. Inorganic salts have been found to evolve at a flow rate of only 200cc/min. in the 800°-925°C temperature range during pyrolysis of bright tobacco. Contrary to a previous report this evolution does not appear to be flow rate dependent. Weight loss experiments continue on cellulose treated with a wide range of inorganic salts in the temperature range of.125°-215°C.and oven times of 2 hours. References: 1. D. L. Simpson, Notebook 7585 2. C. 0. Tiller, Notebook 7603 3. K. R. Squire, Notebook 7440 4. B. E. Waymack, Notebook 7562 5. A. Lewis, Notebook 7666 6. P. A. Wilson, Notebook 7365 7. J. F. Bebbs, Notebook 7449 8. P. E. Phillips, Notebook 7587 M0(