What effect does convection have on evaporation if you leave a petri dish of agar in the fume hood instead of uncovered on the bench (both dry air at 293 K and 1.013 x 105Pa), when you compare mass transfer coefficients (kc fumehood Vs kc_room) and kc_rfumehood). Water evaporates from the exposed area into the still lab air at a rate of 5.73 x 10-6 mole/s (WA_room). In the fume hood, it evaporates into a dry air stream at a rate of 2.29 x 104 mole/s (WA_Fumehood). O No difference O About 2.5 times more O About 10 times more O About 25 times more O About 40 times more

A 10 cm thick piece of beef steak will be frozen in the freezer room -40 ° C. This product has a moisture content of 73%, a density of 970 kg / m³, and a thermal conductivity (frozen) of 1.1 W / (m K). Estimate the freezing time. using the Plank equation. This product has an initial freezing temperature of -1.75 ° C, and the movement of air in the freezing room gives a convective heat transfer coefficient of 15 W / (m² K). t f =       hour

Estimate the thermal conductivity of tomato juice at 35 ° C. (Water content = 87.0% wet basis). Thermal conductivity of material = AnswerW / m ° C

Heat Conduction The wall (thickness L) of a furnace, with inside temperature 800° C, is comprised of brick material [thermal conductivity = 0.02 W m-¹ K-¹)]. Given that the wall thickness is 12 cm, the atmospheric temperature is 0° C, the density and heat capacity of the brick material are 1.9 gm cm-³ and 6.0 J kg ¹ K¹ respectively, estimate the temperature profile within the brick wall after 2 hours. Solve the partial differential equation ƏT = pc at Ə əx (NOT) k subject to the initial condition TX 2L and = T(x,0) = 800 sin and boundary conditions at the inner (x = L) and outer (x = 0) walls of T = 0 x = 0 = 0 ƏT at x = L əx Find the temperature profile at T = 7200 seconds at = 2 hours.

The plot to the right shows the 1-D steady-state solution to the Pennes bioheat equation with T = 37°C at x = 0 (body core) and T = 43°C at x = 0.01 (body surface). The thermal conductivity is 0.5 W m-l °C-'. This scenario describes some surface tissue thermal conductivity (WI(m°C)) 0.5 blood perfusion rate (1/5) T("C) 43 heating (e.g., laser). Which trace represents the highest value of the blood perfusion rate. 42 41 A 40 А. А В. В 39 38 E С.С 0.002 X(m) 0.010 0.004 0.006 0.008 D. D Е. Е

a piece of beef steak 7 cm thick will be frozen in the freezer room -40 degrees Celsius This product has a moisture content of 73% density 970 kg / m³ and a thermal conductivity of 1.1 W / (m K) frozen using the plank equation. This product has an initial freezing temperature of -1.75 degrees Celsius and the movement of air in the raw chamber gives a convection heat transfer coefficient of 10 W / (m² K). tf =

A piece of beef steak 7 cm thick will be frozen in the freezer room -30 ° C. This product has a moisture content of 73%, a density of 970 kg / m³, and a thermal conductivity (frozen) of 1.1 W / (m K). Estimate the freezing time. using the Plank equation. This product has an initial freezing temperature of -1.75 ° C, and the movement of air in the freezing room gives a convective heat transfer coefficient of 15 W / (m² K). t f = ... hour.

The results of air temperature measurement obtained a dry bulb temperature of 29 ° C and a wet bulb temperature of 26.5 ° C. Using a psychometric chart, determine the properties of the air as follows:a. Humidityb. Water contentc. Specific volumed. Enthalpye. Condensation temperatureIf the air is in the space of 162 m3, determine:f. Air weight (dry air and moisture)g. The amount of water content in the room