Gate 3 - Product Analysis

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Contents

Project Management: Coordination Review

Cause for Corrective Action

As we continue to advance in the project, our group maintains successful work ethics and teamwork as we communicate amongst one another with any questions, concerns or suggestions we might have. In completing this gate we came across a few challenges that were, for the most part, resolved while analyzing our engine in greater detail.

The first challenge we faced was not having the proper tools in the laboratory to determine precisely how large our individual components were. We were seeking the weight of such components like our intake manifold cover and piston, as well as the dimensions of the intake manifold cover and connecting rod. To complete this task we had to use the resources available to us as well as the method of estimation. There was a small ruler in the lab that we were able to get some of the dimensions from while with others we had to use an approximated guess. For instance with the intake manifold cover we were able to eye ball the dimensions based off of prior knowledge and experience such as knowing a piece of paper is usually 8.5 inches by 11 inches long so we compared the lengths of a piece of loose leaf paper to the length, width and height of the cover. Same as for the weight, we know how heavy for instance a textbook is so we approximated the weight of our components that way.

A second challenge in this gate was locating the model/part numbers of each component. This posed to be an issue because most of our parts seemed to be "fit", which means they are exact in measurements to the engine in which they belong, and due to the wear of our engine and its components, no serial numbers could be seen. This challenge is considered to be resolved as well as unresolved; part numbers were found based off the type of engine we have and matched up with similar physical characteristics but no definite part used in the Vortec 4300 was found.

Shape description of the components came off as a minor challenge to us. To clearly and effectively illustrate the appearance of the components took some creative thinking on our part. We resolved this by referencing other common shapes and adding adjectives to them to create the best visual for the reader. For instance we described the shape of the rocker arm as an elongated bell shape.

During gate 2 one of our unresolved challenges dealt with the further examination of the valve train. This remains an unresolved challenge due to time constraint and being unable to access a valve compressor.

The last and what seemed to be a major challenge in this gate was creating our solid model using CAD. The issue with this was not having full access to the computers on campus that we were told had the solid modeling programs needed to complete this task. After continually logging-in to numerous computers we were still unable to access these programs. This lead us to have to download inventor from the Autodesk website onto one of our personal laptops in order to complete this section of the gate.

Again we as a group used teamwork and prior knowledge and skills to resolve the challenges we encountered. We worked together to find a reasonable solution we could all agree upon to complete the tasks at hand.

Product Archaeology

Product Analysis

This section was answered based off of the question given in Table 1:Component Assessment Questions, given in Gate 3.

Timing System

Component Function
Timing Chain Timing (Cam) Gear
Image IMG 2962.jpg IMG 2962.jpg
Function Connects the cam gear to the timing gear so that they rotate with one another Rotate the camshaft according to the crankshaft in order for the car to perform well
Energy Flow Mechanical energy Mechanical, rotational energy
Environment Variable pressures Located on exterior of engine block, encased in oil
Component Form
Timing Chain Timing (Cam) Gear
General Shape Single link- symmetrical, All together- free formed circle A circle, with teeth on the edge so that chain will fit in place, radial symmetry
Dimensional 2 dimensional 2 dimensional
Size 2 feet long 5 inch diameter and ½ inch thickness
Relation to function Needs to be circular in order to wrap around the two gears Must be circular to deliver rotational energy
Weight 2 pounds 1 pound
Aesthetics Unpainted flat metal finish Unpainted steel, flat metal finish
Manufacturing Methods
Timing Chain Timing (Cam) Gear
Method Forging Die cast
Reasoning The steel pieces are too small to make by die cast so must be forged with metal Because of its simple shape, it would be the easiest to use this process
Impact of Material None None
Impact of Shape Yes it did because the single pieces of steel are very small None


Component Complexity
Timing Chain Timing (Cam) Gear
Complexity Not very complex Not complex
Scale A single piece is approximately the size of thumb From 1 to 10, 10 being the hardest, a 3
Impact of Previous Categories None A gear is simple to make
Complexity of Interactions Fairly simple The interactions are not very complex


Valve Train

Component Function
Valve
Function Intake fuel and air and expel exhaust gases
Mass Flow Air, Fuel, Exhaust gases
Environment Variable pressure, High Temperature
Component Form
Valve
General Shape Elongated bell - Symmetrical about one axis
Dimensional Two dimensional
Size 1.5in diameter and is 5in long
Relation to function Shape allows for complete seal of combustion chamber
Weight 8 ounces
Aesthetics Unpainted aluminum
Surface Finish Smooth, to reducing friction and seal combustion chamber
Manufacturing Methods
Valve
Method Turned
Reasoning Axial symmetry
Impact of Material Turned because of shape not material
Impact of Shape The part must have axial symmetry
Component Complexity
Valve
Complexity Not very high because of its axial symmetry and small size
Scale From 1 to 10, 10 being the most complex, 1
Impact of Previous Categories Because of the shape and material, it is very simple to create this product
Complexity of Interactions Not very complex, In comparison to the other parts of the engine, valves are very simple


Rotational Assembly

Component Function
Oil Pan/ Oil Pump Connecting Rods Piston
Image IMG 2964.jpg IMG 2972.jpg IMG 2972.jpg
Function Lubricates the camshaft and other parts Attach the piston to the crankshaft Conversion of pneumatic energy to translational linear energy - Change the pressure in the cylinder to allow the auto cycle to function correctly
Flows Mass Flow - moves oil around engine Energy - Mechanical, linear energies Mass - Air, Fuel, Exhaust

Energy - Heat, Pneumatic, Linear

Environment High temperatures, beneath engine High temperatures and constant movement in the engine block Variable pressures and high temperatures


Component Form
Oil Pan/ Oil Pump Connecting Rods Piston
General Shape Pan- a square attached to a rectangle; Pump- abstract shape A symmetrical, two pronged fork Short Cylinder - Perfectly circular, two small impressions where the valves would open
Dimensional 3 dimensional 2 dimensional 2 dimensional
Size 1.5 ft X 1 ft X 1 ft 6 inches long and ½ inch thick, 1 inch at skinniest point and 4 inches at its widest point Radius of 5.5cm and a height of 7.5cm
Relation to function Shape must make it possible to fit underneath engine and enclose the bottom Must be able to wrap around the crankshaft and support the piston’s movements Piston is circular because the bores of the cylinders are circular
Weight 5 pounds (altogether) 1 pound About 5 pounds
Aesthetics Unpainted metal, silver because it is on the bottom of the engine where it is not visible Unpainted steel because cannot be seen Silver, unpainted with a poor finish from casting


Manufacturing Methods
Oil Pan/ Oil Pump Connecting Rods Piston
Method Pan - Die Cast; Pump - Machining Die cast Casting and machining
Reasoning This would be the easiest way to manufacture this product Easiest way to achieve shape of connecting rod Rough surface finish were it does not come in contact with other components
Impact of Material None None Aluminum because for it low density and good thermal loading
Impact of Shape Yes, because of the odd shapes of both objects Yes None


Component Complexity
Oil Pan/ Oil Pump Connecting Rods Piston
Complexity Fairly complex shapes but simple purpose Fairly simple Fairly complex, good amount or surfaces and sub-components
Scale From 1 to 10, 10 being the most difficult, 3 From 1 to 10, 10 being the most complex, a 2 From 1 to 10, 10 being the most complex, a 6
Impact of Previous Categories They do not Does not significantly impact the complexity It must be made of a good, strong metal and must be manufactured well because of the amount of friction applied to the product
Complexity of Interactions Simple, compared to other systems of the vehicle Compared to other parts of the engine, connecting rods are fairly simple Not very complex interactions in comparison to other parts of the engine


Cooling System

Component Function
Water Pump Thermostat Electric Water Sensor
Image IMG 3018.jpg IMG 3018.jpg IMG 3018.jpg
Function It circulates the water/coolant throughout the engine and the radiator, keeping your engine from overheating To bring and maintain the engine up to optimum operating temperature Measures the engine coolant temp and responds to change in ECT by way of the ECM (engine control module)
Materials Used Iron and brass Iron (stainless steel) Brass housing
Manufacturing process Casting and machining Casting Casting

Solid Model Assembly

Autodesk Inventor was used to model the valve train of the engine. This program was used since Matt is familiar with this software from previous use. The valve, spring, washer, rocker arm, push rod, and lifter were chosen due to their close positioning in the engine and their importance to the overall function. Each part is shown separately below along with an assembly and a link to a video. A link to a .zip file of the CAD models is also shown below.

Valvetrain Assembly

File of CAD Models

CAD Valvetrain Assembly

Part CAD Image
Lifter

CAD Lifter.jpg

Push Rod

CAD Push Rod.jpg

Rocker Arm

CAD Rocker Arm.jpg

Washer

CAD Washer.jpg

Spring

CAD Spring.jpg

Valve

CAD Valve.jpg

Engineering Analysis

The main function of an engine, which is to produce usable power that a vehicle can use to move, is what all of the engine's sub functions and components support. An engineering analysis can be applied to any sub system of the engine, but more globally, can be applied to the entire engine itself. This type of analysis would be to determine important overall specifications of the engine before the engine was going to actually be manufactured. Some of these important engine specifications would be power and mean effective pressure.

Problem Statement:

The problem statement associated with this type of analysis would vary depending on what the engineer wanted to test. In this particular example, we will be establishing the power developed by a certain brake mean effective pressure of the cylinder. Thus the problem statement would display that while saying the mean effective pressure being tested, and for this example we will use a b.m.e.p. of 150 psi. This is a high brake mean effective pressure, which can be used in this engine due to the high strength of the block and pistons.

System Diagram

Assumptions:

The assumptions of the analysis can vary extremely depending on what variables an engineer is attempting to test. In this analysis we are testing a particular brake mean effective pressure, therefore it will be an assumption. Conversion factors that will be used in the analysis are also very important. In this analysis our assumptions are:

  • Brake Mean Effective Pressure = 150 psi
  • 1 hp = .7457 kW
  • Swept Volume = Engine displacement = 4300cc = .0043 cubic meters
  • Maximum RPM = 55000 rpm
  • Assume Four Stoke Engine
  • 1 bar = 14.5 psi

Governing Equations:

For this section of the analysis there is only really only one equation, the equation for power of an engine. However the conversion into horsepower and conversion of b.m.e.p. into bar is also important.

  • 1 bar = 14.5 psi
  • 1 hp = .7457 kW
  • Power Output = 50 X b.m.e.p. (bar) X Swept Volume (cubic meters) X Revolutions per Second (rps) X Cycles per Rotation

Calculations:

  • 1 bar = 14.5 psi
  • (150psi)(1bar/14.5psi)
  • (150psi)(1bar/14.5psi)= 10.35 bar


  • Power Output = 50 X b.m.e.p. (bar) X Swept Volume (cubic meters) X Revolutions per Second (rps) X Cycles per Rotation
  • Power Output = 50 X (10.35 bar) X (.0043 cubic meters) X (5500rpm/60s) X (2 cycles)
  • Power Output = 407.9 kW
  • Power Output = 547 hp

Solution Check:

Here we will use what is called a unit check, in order to check to ensure the units of the equation work.

  • Power Output = 50 X b.m.e.p. (psi) X Swept Volume (cubic meters) X Revolutions per Second (rps) X Cycles per Rotation
  • Power Output = (psi)(cubic meters)(rps)(Cycles per Rotation)
  • Power Output = (bar)(cubic meters)(rps)(Cycles per Rotation)
  • Power Output = (N)(square meters)/(s)(s)(s)

N-m/s^3 = J/s = Watts

As shown, you can see the units in the equation equal joules and therefore the equation checks

Discussion of Results:

After the calculations have been obtained it from the analysis, we must say what these results mean. In our case it is important to emphasize the fact that with a brake mean effective pressure of 150 psi, our engine achieves a power of 445 hp. This answer is obviously not the power output the engine currently achieves, but what it could achieve with the given brake mean effective pressure.

Design Revisions

The General Motors Vortec 4300, while engineered at a high level of excellence at it's time of development, can be majorly improved due to the increases in current technology. These design revisions can also be made while keeping constant the intended use of the engine, as well as the target price point relative to the time it was produced.

The engine block of the Vortec 4300 is made of cast iron, a very heavy and inexpensive metal. At the time of production the use of cast iron from the engine block was feasible due to its relative high strength, low cost, and low production cost. However with current technology, an aluminum engine block is much more feasible. The use of an aluminum engine block can reduce the weight by almost 50% compared to its' cast iron equivalent. This dramatic decrease in weight positively affects the fuel consumption of the car, making it far more environmentally friendly. Decreased vehicle weight also increases societies view of the car, making the vehicle more fun to drive, increasing consumer satisfaction. The use of an aluminum engine block also allows the actual block to have a far greater resistance to rust and other environmentally degrading factors. Lastly the costs of aluminum have decreased since the design of this engine, therefore the actual material cost of the engine would increase only slightly, having almost no negative impact on economic design factors. For these reasons it would be beneficial to revise the design of the engine block to have it cast of aluminum.

Along with the material of the engine block, many of the materials of the Vortec 4300 can be changed to improve the design of the overall engine. However the most important being the rotating assembly of the engine, being the main component of the engine that provides the main function of the engine. At the time of the design of the Vortec 4300, engine displacement was a major consideration, instead of rotational efficiency or mechanical efficiency. Therefore although the engine displaces a relatively large amount compared to most six cylinder engines, it seriously lacks in refinement and efficiency of power. This can be revised by changing the rotating assembly sub system, changing the material to a light weight alloy which if forged, not cast iron. This change greatly reduces the rotating mass of the assembly, therefore causing less frictional losses and creating more power by the engine while also consuming less fuel. This portrays the economical design considerations with using a lighter weight material for the rotating assembly, while also improving societies perception of the engine. While this material change would be relatively more expensive than would be considered in the exact same price point, the increase in performance, efficiency, and reliability would be factored into the engine's overall design considerations.

The Vortec 4300 utilizes a mechanical water pump to circulate the coolant through the engines cooling system. This means that it is belt driven by the rotational energy of the crankshaft transferred via a belt to the water pump. At the time of design, this was a feasible and acceptable method of circulating the fluid. However with the technological advancements of today, this method is no longer the most beneficial way to accomplish this task. This mechanical water pump can easily be replaced by an electric water pump for many reasons, the most important of which being the rotational drag on the engine that a mechanical water pump causes. This rotational drag is deleted by an electric water pump because this type of water pump takes energy from the vehicles battery, which is stored there instead of taking from the rotational energy of the crankshaft. This elimination of the water pump drag increases overall engine efficiency, showing its beneficial environmental consideration. The electric water pump revision also illustrates the economical design considerations by saving in overall parts, belts and systems involved with a mechanical water pump. While the Vortec 4300 was very well design from the factory, over time some of the technology has improved allowing for beneficial design revisions to the product.

Component Summary


Table 1:Component Summary
Component Name Quantity Used Function Material Manufacturing Process Fastener Used
Throttle Body 1 Control the flow rate of air into the engine Aluminum The throttle body is made of for smaller parts, a spring, the body, a valve, and a trigger that were most likely casted Three (3) 10mm Bolts
Intake Manifold Cover 1 Protect the engine control and unit and fuel injectors Plastic Based on the shape and material the cover was most likely casted Ten (10) 10mm Bolts
Distributor 1 Tell the spark plugs when to ignite Plastic and Steel Molding for the plastic and steel One (1) 10mm Bolt
Fuel Injection Sub-System 1 Manage injection of fuel into cylinder heads Plastic This part is very similar to the cover so it is most likely casted One (1) 8mm Allen Bolt
Intake Manifold 1 Direct air into each cylinder head Aluminum This part has visible parting rings which is one of the signs of metal casting Eight (8) 13mm Bolts
Valve Train Cover 2 Protect the valve train system Plastic The clean, uniform curves and indents suggest casting Three (3) 13mm bolts
Rocker Arms 12, 6 per cylinder head Connect the valve springs to the pushrods Steel Its shape and material most likely means it was casted One (1) 13mm bolt each
Pushrods 12, 1 per rocker arm Turn the rotational energy of the cam into linear energy for the valve springs Steel It may start from one long rod then machined down into each individual rod One (1) Rocker Arm
Exhaust Manifold 2, one per cylinder head Direct the exhaust gases away from the engine block Iron The clean curves and embossed marks suggest casting or forging Six (6) 14mm bolts
Cylinder Head 2 Manage the intake of fuel and removal of exhaust, house valve springs and the valves Steel Clean curves and embossed lettering marks suggest casting or forging Seven (7) 13mm Bolts