A 15-cm-diameter aluminum ball is to be heated form
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Heat and Mass Transfer: Fundamentals and Applications
- During the process of raising steam in a boiler, when the pressure was 1.9 bar gauge the temperature inside the boiler was130°C and when the pressure was 6.25 bar gauge (0.625 MPa) the temperature was 165°C. If the volume of the steam space is constant at 4.25 m. Calculate the mass of steam. Steam Properties : Steam at 130°C P 2.7 bar Vg 0.6686 m3/kg 5.356 kg 4.356 kg 6.356 kg 3.356 kgarrow_forward41.394 kg per second of water at 0.03398675 kbarg and internal energy of 15000 kW is heated at constant pressure to saturated vapor and further heated at constant volume process until the pressure is quadrupled. Determine the ratio of the heat added during the constant volume process to the heat added during the constant pressure process. For the steam table, please refer to the green book entitled " Thermodynamic Properties of Water Including Vapor, Liquid, and Solid Phases"arrow_forwardAs the insulation around an adiabatic and frictionless piston-cylinder system is removed, 42500 J heat is lost to the surrounding. As a result, the gas in the cylinder contracts and hence 400 dm3 volume of the gas in the cylinder becomes half. Having that the atmospheric pressure is 100 kPa and the weight on the piston exerts additional 5 kPa, determine the change in the internal energy of the gas during this process.arrow_forward
- 2. 3 mol of air are contained in a piston-cylinder system with a surface of S = 5 m², loaded with a spring. The piston-cylinder system lies in a vertical plane, such that gravity acts on the piston. The initial pressure and temperature of the system are 25 kPa and 750 K, respectively. In the initial condition, the spring is unstretched. Heat is transferred from the air in the cylinder, which is cooled down to 200 K. In this quasi-static process, the volume is reduced to a third of the original one, stretching the spring. At the end of the cooling process, the spring snaps and the piston falls down, compressing the gas. This transformation happens fast, so that no heat is exchanged, but the transformation is non-quasi static. The end state of this compression is an equilibrium, with a volume equal to 85% of its value at the end of the quasi-static cooling process. Find: i) the heat that is transferred from the air within the cylinder during the quasi-static cooling, before the snapping…arrow_forwardThere is an 500g container made out of aluminum holding 300g of water. The Water and Aluminum have reached thermal equilibrium at 40 degrees Celsius. A 200g block of iron at a temperature of 0 degrees Celsius is later dropped into the water. Using the specific heat for water=4180J/kg/C. The specific heat for aluminum is 900 J/kg/C. The specific heat for iron is 450 J/kg/C. The final temperature of the three materials will be degrees celsius. The thermal energy of the water changes by Joules. (give an amount and include a + if it increases and a - if it decreases) The thermal energy of the aluminum changes by Joules. (give an amount and include a + if it increases and a - if it decreases) The thermal energy of the iron changes by Joules. (give an amount and unit and include a + if it increases and a - if the value decreases)arrow_forwardInitially saturated water liquid at 200°C is contained in a piston-cylinder. The water is then heated isothermally until its volume is 100 times larger than its initial volume. 1. Determine the increase in energy (kl/kg) of the water. 2. Determine the work transfer (kJ/kg) and indicate whether it is into or out of the system. 3. Determine the heat transfer (kJ/kg) and indicate whether it is into or out of the system. saturated water 200arrow_forward
- A cylinder contains 3 kg of oxygen at 5 bar pressure and temperature of 27°C. Determine the volume of the cylinder. A closed system receives 105 kJ of heat whila it performs 130 kJ of work. Determine the change in internal energy.arrow_forwardAmount of gas is contained in a piston-cylinder assembly with initial volume V1 = 0.9 m3. Now, it expands to V2 = 1.4 m3. During the expansion process, the gas pressure maintains constant at p = 0.2 MPa. The internal energy of gas is increased by 12 kJ during the expansion process. Determine: (1) The heat transfer of gas during the process, in kJ. (2) The velocity of the piston at the final state, if the piston has the mass of 20 kg and initially is stationary.arrow_forwardDetermine the internal energy change for carbon monoxide, in kJ/kg, as it is heated from 312° K to 1456° K, using the ideal gas properties tablearrow_forward
- Initially saturated water liquid at 200°C is contained in a piston-cylinder. The water is then heated isothermally until its volume is 100 times larger than its initial volume. 1. Determine the increase in energy (kJ/kg) of the water. 2. Determine the work transfer (kJ/kg) and indicate whether it is into or out of the system. 3. Determine the heat transfer (kJ/kg) and indicate whether it is into or out of the system. saturated water 2000 Earrow_forwardA student living in a 4-m x 6-m x 6-m dormitory room turns on her 150-W fan before she leaves the room on a summer day, hoping that the room will be cooler when she comes back in the evening. Assuming all the doors and windows are tightly closed and disregarding any heat transfer through the walls and the windows, determine the temperature in the room when she comes back 10 h later. Use specific heat values at room temperature, and assume the room to be at 100 kPa and 15°C in the morning when she leaves. ANS. 58.2 Carrow_forwardA student living in a 4-m x 6-m x 6-m dormitory room turns on her 150-W fan before she leaves the room on a summer day, hoping that the room will be cooler when she comes back in the evening. Assuming all the doors and windows are tightly closed and disregarding any heat transfer through the walls and the windows, determine the temperature in the room when she comes back 10 h later. Use specific heat values at room temperature, and assume the room to be at 100 kPa and 15°C in the morning when she leaves.arrow_forward
- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning