MECHANICAL ENGINEERING JOB INTERVIEW QUESTIONS :- 1.) What is the direction of tangential acceleration ? Ans:The direction of tangential acceleration may be same or opposite to that of angular velocity. 2.)Why excess air is required to burn a fuel completely ? Ans: Excess air is required to ensure adequate mixing of fuel and air, avoid smoke, minimize slagging in coal burning, and to ensure maximum steam output. 3.)Which type of plant will you recommend for remote location if power is required in six to twelve months time ? Ans: Diesel engine power plant. 4.)What do you understand by forced convection ? Ans: When convection heat transfer occurs between a solid body and a fluid and where circulation of fluid is caused and controlled by some mechanical. 5.). What is Sentinel Relief Valve? Ans. It’s a special type valve system. The valve will open when exhaust casing pressure is excessive (high). The valve warns the operator only; it is not intended to relieve the casing pressure. 6.)What is boundary layer thickness in turbulent boundary layer ? Ans: In ease of turbulent boundary layer, boundary layer thickness is defined as the distance from solid surface at which the fluid velocity is 99% of the undisturbed free stream velocity. Near the surface of solid, there is laminar flow which changes to buffer zone and finally turbulent region. 7.). Stirling cycle with regenerative arrangement and Carnot cycle operate within same temperature limits. What can be said about thermal efficiencies of these two ? Ans: Thermal n of both will be same. 8.). What is the frequency of secondary imbalance in four-stroke engine ? Ans: Two times the engine speed. 9.)What is the difference between Specification,Codes, Standards? Ans. Specification is describing properties of any type of materials. Code is procedure of acceptance and rejection criteria. Standard is accepted values and compare other with it. 10.) What is difference between Welding and Brazing? Ans. In Welding concentrated heat (high temperature) is applied at the joint of metal and fuse together. In Brazing involves significantly lower temperatures and does not entail the melting of base metals. Instead, a filler metal is melted and forced to flow into the joint through capillary action. 11.)What is the purpose of Scrapper Ring? Ans. It scraps the excess lube oil from the cylinder walls. there by preventing oil from entering combustion zone. 12)What is DTSI Technology? Ans. DTSI stands for Digital Twin Spark Plug Ignition. The vehicles with DTSI Technology use 2 spark plugs which are controlled by digital circuit. It results in efficient combustion of air fuel mixture. --»Digital - Since the spark generation will be initiated by a microchip. --»Twin - Since two spark plugs will be used. --»Spark ignition - Since the ignition will be done via a spark. 13.)What is the difference between Sudden Force and Impact Force? Ans. An impact is a high force or shock applied over a short time period when two or more bodies collide. A force which applies on the body (material) suddenly is known as sudden force. 14).What is ATFT Technology used in Honda Hunk? Ans.-ATFT means Advance Tumble Flow Induction Technology, Tumble flow means swirling. In this technology fuel air mixture from the carburetor into the engine cylinder with a swirl action. The advantage being one gets a more efficient burning of fuel hence more power and better fuel economy with lesser emissions. 15).Why we do not use same technology to start both SI /CI engine Ans.-The S.I. or spark ignition engine uses petrol as a fuel and the C.I. or compression ignition engine uses diesel as a fuel. Both the fuels has different compression ratio. In SI engine the compression ratio is 8-12:1. In CI engine the compression ratio is 16-22:1. So in case of SI engine, the compression ratio is not sufficient for fuel to burn so a spark plug is used, whereas in ci engine, the compression ratio is so high that due to its internal hea
Posted on: Wed, 21 Jan 2015 07:33:03 +0000