A plain bearing used in industrial application operates at high speed under very high loads. All elements of this plain bearing (bearing and journal) are made of 080M40 steel. In order to prolong the life of the mattress, you are asked to replace one element of the plain bearing with the materials in the list below (journal or bearing will replace only one). Why which material would you choose?

1. Rice
2. Bullet
3. Teflon

Note to question 1: To reach the answer to the question, you will draw conclusions from the results by using a number of formulas to reach the behavior of different materials in contact.

I need 7 to 12 page report on this topic

Discuss the difference between the ideal and the actual indicator diagrams of four stroke SI engine.

Consider a steam power plant that operates on a reheat Rankine cycle and has a net power output of 80 MW. Steam enters the high-pressure turbine at 10 MPa and 500°C and the low-pressure turbine at 1 MPa and 500°C. Steam leaves the condenser as a saturated liquid at a pressure of 10 kPa. The isentropic efficiency of the turbine is 76 percent and that of the pump is 95 percent.

A: Determine the quality (or temperature, if superheated) of the steam at the turbine exit.

B: The thermal efficiency of the cycle.

C: The mass flow rate of the steam

A cylindrical bronze sleeve (2) is held in compression against a rigid machine wall by a high-strength steel bolt (1), as shown in the figure. The steel [E = 199 GPa; α = 11.7 × 10^-6/°C] bolt has a diameter of 24 mm. The bronze [E = 110 GPa; α = 22.0 × 10^-6/°C] sleeve has an outside diameter of 73 mm, a wall thickness of 9 mm, and a length of L = 550 mm. The end of the sleeve is capped by a rigid washer with a thickness of t = 4 mm. At an initial temperature of T₁ = 14°C, the nut is hand-tightened on the bolt until the bolt, washers, and sleeve are just snug, meaning that all slack has been removed from the assembly, but no stress has yet been induced. If the assembly is heated to T₂ = 88°C, calculate

(a) the normal stress (positive if tensile and negative if compressive) in the bronze sleeve.
(b) the normal strain (positive if stretched and negative if compressed) in the bronze sleeve.

What is the equation for the thermal time constant? What is the physical significance of the thermal time constant? Can you determine the validity of lumped capacitance from the thermal time constant if given the Fourier number?

in a crank and slotted lever quick return mechanism, as shown in figure the driving crank length is 75mm. the distance between the fixed centres is 200mm and the length of the slotted lever is 500mm. find the ratio of the times taken on the cutting and idle strokes. determine the effective stroke also

6. Water steadily enters an extremely thin 100 m stainless steel pipe with a diameter of 10 cm at a mass flow rate of 31.4 kg/s at 80 °C at 100 kPa. The convection heat transfer coefficient between the ambient air (20 °C) and water pipe is ℎ = 120 ?/(?^2)?. You can ignore the heat loss by radiation and assume the temperature of the water and pipe surface are almost same but the temperature Difference is very small but enough for conduction heat transfer. Please find the variation of the water Temperature with length of pipe (from entrance), the heat loss from water to ambient air when passing through this pipe. You can assume the specific heat of water is 4.2 kJ/(kg*Celsius). Please keep in mind that the temperature of the pipe surface is a function of the length, so that heat loss through convection is not constant but a function of pipe surface temperature. In solving this question, you can assume the water in this pipe consists of a series of small elements (discs). For each element (disc), the heat loss through side (pipe) surface by convection is equal to the change of thermal energy (temperature change noted as dT) of water flowing through this element (disc). This will lead to the development of a differential equation: ?? ?? = ?? + ?. You can find the temperature as a function of x noted as ? = ?(?), and heat transfer as a function of ?(?) = ?(?).

Discuss a minimum of two complex systems that you have encountered in your profession. Define why you think that they were complex.

A shaft cycles such that each bearing undergoes the radial loads of 30% of the time at 20kN, 50% of the time at 25kN, and 20% of the time at 30kN. If the design life of a bearing is to be at least 5e6 revolutions, select the smallest 03 series cylindrical roller bearing that will accomplish this.

Explain in details the environmental impact of ballast water in ship operation and discuss the role of the International Convention for the Control and Management of Ships' Ballast Water and Sediments (Ballast Water Management Convention or BWM Convention). Your answer should not be more than 2 pages (typed).

3. Use oil-tempered 0.060” diameter wire to make a spring with squared and closed ends, a
spring index of 4, and solid length of 1.25”. Use a load factor of safety of 1.05 and make the free
length 1.75 inches.

e) What is the force to close to solid, Fs?
f) What is the critical frequency?
g) What is the factor of safety, solid, ns?

1. Activity network diagram is used to develop a work schedule for the facilities design effort. Activity A to K is descried as follows: A with a duration of 2 month; B has immediate predecessor of A with total duration of 4 month; C has immediate predecessor of (A) with total duration of 2 month; (D) has immediate predecessor of B with total duration of 2month; (E) has immediate predecessor of B and C with total duration of 4 month; (F) has immediate predecessor of A and E with total duration of 6 month; (G) has immediate predecessor of D with total duration of 4 month; (H) has immediate predecessor of D, E, F with total duration of 2 month; (I) has immediate predecessor of H, F with total duration of 6 month; (J ) has immediate predecessor of H and F with total duration of 6 month, (K) has immediate predecessor of H, I, J with total duration of 4 month. What is the project duration and the critical activities?

3. If you are required to build Wind Turbine for industrial application, which factors will you consider? Hint: Approach the question through creative thinking.

Food security is among one of the key priority areas for many nations worldwide. Significant climate change resulting from global warming such as erratic weather patterns, prolonged draught and flooding present tremendous challenges to traditional farming. While conventional farming methods have sustained mankind since eons ago, these methods increasingly struggle to feed the burgeoning world population. Many uncertain factors faced by conventional methods include unpredictable weather or climate, rising material and labour costs, pestilence and disease as well as competition of land and water resources with the current population. Overfishing, waste plastic contamination, water pollution and dense aquaculture have led to dwindling supply and potentially contaminated seafood. High demand for poultry also resulted in the rising cost of feed and dubious supplements to enhance animal growth. Among the negative consequences include unequal food distribution (hunger or malnourishment versus food spoilage or waste at different locations), air and water contamination, extinction of wildlife, increased consumption of resources (water, land) and potentially, rise in overall food prices with shortage of food supply.

Select and briefly analyze two (2) challenges for a nation to maintain food security. Subsequently, design a control system that can help to address these challenges of food security. You are recommended to accomplish this task by fulfilling the following: (a) Illustrate the control system via a sketch. (b) Justify the selection of the major components of the control system (c) Explain the working principle of the control system.