MED_6_TAT Thermofluids and Turbomachinery Coursework Brief 2026 | LSBU

MED_6_TAT Thermofluids and Turbomachinery Coursework Brief 

Guide to Laboratory Practical Works

This guide provides information on the laboratory programme carried out in the Thermofluids and Turbomachinery module (ENG_6_TAT). During the study of the unit, you will attend a practical laboratory session. This session will be timetabled for you once you have been allocated to a lab group.

Locations for Experimental Works

The TD200 small engine test set is the main apparatus for the IC engine experiment, which is located in Room E135, Extension Block building.

Health and Safety in Laboratories

Laboratories and practical workspace are potentially dangerous places. Therefore, you must follow the instructions below to work safely:

• Qualified academic and technical staff must be present whenever this experiment is performed.
• Please listen to the academic and technical staff in the laboratory and follow their instructions.
• Familiarise yourself with the instructions for your experiment before starting work.
• Work only on the equipment you are assigned to and follow the given instructions.
• No food or drink in the laboratory. (No mobile phone calls to be made or received during the laboratory session).

Experiment

Internal Combustion Engine Performance 

1: Introduction

The engine is a device that converts thermal energy to mechanical energy. The thermal energy is produced from the combustion of hydrocarbons in the presence of oxygen in an exothermic reaction commonly called the combustion reaction. The Second law of thermodynamics is the basis of all types of heat engines.

1.1: Purpose/Aim:

Understand the most important features of the internal combustion engine, including the thermodynamic cycle and performance characteristics.

2: Equipment

The TD200 small engine test set is designed for laboratory experiments; it is a single-cylinder and four-stroke internal combustion engine. The TD200 small engine test set consists of two main parts, as follows:

• The testbed with a dynamometer
• A bench-mounted instrument frame. Figure 1 shows the layout of the TD200 engine

Figure 1 shows the layout of the TD200 engine.

Figure 1: The general layout of the TD200

The working principle of one working cycle of four strokes engine consists of four processes as follows:

• Suction process (Induction)
• Compression process
• Expansion process (Power)
• Exhaust process

Each process is completed in one stroke of the piston, and one working cycle is completed in four strokes of the piston, as seen in Figure 2.

Figure 2: Four Strokes in one working Cycle of Piston

3: Procedure

The following procedure is to be followed:

• The engine needs to be fixed in the right position; the fuel tank must be filled with the correct amount of fuel, and the exhaust system needs to be connected before starting the experiment.
• Pull the starting handle of the test engine until it can be felt that it has passed the compression stroke and is easy to turn. Allow the starting handle to return to its original position.
• Gently rock the Dynamometer, then press the ‘press and hold to zero’ button on the Torque and Speed display. This will zero the Torque reading.
• Press and hold the ‘Zero airbox pressure’ button on the DPT1 board. Release the button; the differential pressure is now zero.
• Open both valves on the fuel gauge- (turn the valves so that they are in line with the fuel pipe).
• Make sure that the fuel has passed down the fuel feed pipe to the engine.
• Turn on the water supply to the Dynamometer. Open the control valve by half a turn. Fully open the water outlet valve. Make sure that water flows through the Dynamometer.
• Allow the engine to reach the normal operating temperature, then set the test engine throttle for maximum speed.
• Adjust the Dynamometer control valve to increase the load on the engine and decrease its speed to its lowest stable speed.
• Use the Dynamometer control valve to maintain the engine speed at the lowest stable speed within 1400±100 rpm. Record the test engine fuel consumption. [Shut the fuel inlet valve and use a stopwatch to measure the time taken to drain 8 ml (see figure 3 below). Re-open the inlet valve before the engine is starved of fuel. (The fuel consumption could be measured automatically via the fuel gauge (DVF1))]

Figure 3: Fuel Measurement

• Use the blank results table (Table 1- page 9) attached to this guide to record the test results.
• Use the water flow through the Dynamometer to allow the engine speed to increase by about 250 rpm. Again, use the Dynamometer control valve to maintain the new speed and record the fuel consumption and other results in the results table.
• Repeat for other speeds in steps of about 250 rpm and record the results.
• After taking the readings, use the engine rack to reduce the engine speed to a stop. Then turn off the fuel supply to the engine.

Results and Assessment

The laboratory assignment will be assessed through a professional report format, including the following Seven Tasks:

Task 1: (30 marks)

Calculate and present in a table the following performance characteristics:

• Power (kW)
• Brake Mean Effective Pressure (BMEP) (kPa)
• Fuel mass flow rate (kg/hr)
• Specific Fuel Consumption (SFC) (g/kWh)
• Air volumetric flow rate (m3/hr)
• Air mass flow rate (kg/hr)
• Air-Fuel Ratio (AFR)
• Volumetric efficiency (%)
• Brake thermal efficiency (arbitrary overall efficiency) (%)

(Unless otherwise stated, equations for calculations should be taken from lecture notes and not supporting documentation from the testbed manufacturer.

(Note: Worked calculations for one of the engine speed sites, and a short description and note of key equations must be included in your report.

Task 2: (30 marks)

Plot on graphs the following performance characteristics vs engine speed (rpm):

• Torque (Nm) 
• Power (kW) 
• BMEP (kPa)
• Mean piston speed 
• SFC (g/kWh)
• AFR & lambda 
• Volumetric efficiency (%)
• Brake thermal efficiency (arbitrary overall efficiency) (%) Exhaust temperature (ºC)

(Note: Graphs must be done in MS EXCEL/ Matlab and included in your report. Provide a concise explanation of each of the trends observed in your graphs of performance characteristics.

Task 3: (10 marks)

Correct the measured Torque and Power to standard conditions according to the formula given below. Plot on an additional graph the Corrected and Raw powers:

Take the measured pressure to be the pressure of dry air in the absence of humidity data.

(Note: Worked calculations for one of the engine speed sites of data and a short description of the equation must be included in your report.

Task 4: (10 marks)

Choose one test site on which to construct an Energy Balance diagram. Indicate fuel energy input, Brake work output, Heat loss to coolant, and heat loss to exhaust. Comment on your results and compare them to published literature.

Task 5: (5 marks)

Discuss briefly the process of ignition and combustion in spark ignition (SI) engines. Show the process on a P-CA (pressure – crank angle) diagram, listing key stages in the process.

Task 6: (5 marks)

State five harmful pollutants that can be found in the exhaust gas of internal combustion (IC) engines, and describe briefly what they are.

Task 7: (10 marks)

Report presentation and clarification of the results.

(Note: The report must include worked calculations, a short description, a note of key equations and a clear discussion and conclusion of the results.

5: Useful information and Data

Capacity (manufacturer data) 208 cc or 208 cm3 (0.208 L)
Stroke    54 mm
Bore    70 mm
Compression ratio    8.5:1
Fuel specific gravity    0.74
Fuel Calorific value        43,800 kJ/kg Typical Specific Heat of Exhaust Gases    1 kJ/kg K
Maximum power absorption    7.5 kW@ 7000 rpm
Maximum Torque    15 Nm
Orifice diameter (nominal)    18.5 mm with Cd =0.6

For Air Consumption Calculation