| Author | Suministrado, Delfin Coronado |
| Call Number | AIT Thesis no.AE-79-24 |
| Subject(s) | Rice--Thermal properties
|
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Abstract | Surface area, specific heat, thermal conductivity and thermal diffusivity of rough rice were determined experimentally.
Surface area values determined by the coating method were found to be dependent on the grain size of the sample, amount of the varnish and the size
distribution of the metal powder used. The surf ace area values ranged between 17.34 cm,2/gm. and 20.32 cm,2/gm/ Specific heat values determined from the method of mixture were found
to increase with the moisture content and temperature of the test sample, A generalized equation was developed for the specific heat as a function of
the temperature and moisture content. At 8%, 13%, 20% and 25% moisture content (wet basis) and at initial temperatures of 28°c, 4ooc, 50°C and 60°c,
the specific heat values were between .4089 cal./gm.ํc and .5768 cal./gm.0c. Thermal conductivity measurement using the steady-state method resulted in higher values than the values based on the transient method. It took
long hours to attain the steady-state conditions in the test apparatus. As a result, considerable moisture changes were observed in the sample during the process of thermal conductivity determination. The thermal conductivity
determined by the steady-state method and the transient method increased linearly with the sample moisture content and temperature. The effect of temperature on the thermal conductivity from steady-state method was more predominant
than the effect of moisture content. The thermal conductivity values from
transient method were more influenced by the m0isture content. Comparatively,
thermal conductivity values from transient method are 50% lower than the
values found by steady-state method. Values of thermal conductivity determined
by steady-state method ranged between .1752 watt/m.0c to .. 2551 watt/m.0c at
8%, 13% and 20% moisture .content l evels and mean temperatures of 38.5°c,
42.0°c and 47.5°C. Values of thermal conductivity determined by transient
method ranged between .0814 watt/m.°C and .1239 watt/m. 0c.
Thermal diffusivity values cal culated from the steady-state thermal
conductivity values and the specific heat decreased linearly with moisture
content but increased linearly with temperature. However, thermal diffusivity
values were observed to be insensitive to variation of moisture content and
temperature when using the thermal conductivity values based on the transient
method. Thermal diffusivity values from steady-state thermal conductivity
values were between ,0005979 m.2/hr. and .0007154 m; 2/hr. at 8%, 13% and
20% moisture content levels and at mean temperatures of 38.5°c, 42.2°c and 47.5°c. From transient method, the values were between ,0002777 m. /hr. and .0003100 m. /hr.at moisture content levels at 8%, 13%,20% and 25% and initial
temperatures of 28°c, 40°c, 50°c and 60°c. |
| Year | 1979 |
| Type | Thesis |
| School | School of Environment, Resources, and Development |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Agricultural and Food Engineering (AE) |
| Chairperson(s) | Jindal, Vinod Kumar |
| Examination Committee(s) | Gee-Clough, D. ;Exell, Robert H.B.
|
| Scholarship Donor(s) | USAID/RED |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1979 |