# Search results

1. ### Calorific value of Petrol

Hi I am bit confused regarding the heating/calorific value of petrol (used for vehicle) extracted from crude oil and from liquefaction of coal. Should they be same? or Petrol extracted from crude oil will have different calorific value compared to the petrol from liquefaction...
2. ### Wave Propagation in Vibrating Solid

Hi I am very confused at determining the type of elastic wave in a vibrating body. For example, an elastic solid is flexuraly vibrating in one of its resonant mode. There should be elastic wave excited from this vibration. But, my question is which wave will be excited through it...
3. ### Numerical Integration of Double integrals

I have a double integral: ∫∫sin^2(∏x/A)*sin^2(∏y/B)dxdy A=length along x B=length along y ranges: 0 to A(for x) & 0 to B (for y) Analytical result is: A*B/4 (unit^2) Now, I want to evaulate it numerically using trapezoidal rule. Infact, I have done it but not sure whether it is a right...
4. ### Polar Integration

Hi I have a function [e.g. f(r)] which I want to integrate over r and θ. What would be the integration form? Which one is correct? ∫∫f(r) drdθ OR ∫∫f(r) rdrdθ Please explain. Also, can it be said as area integration as well like the one in cartesian coordinate?
5. ### Area of the Curve

Hi How can I calculate the area of the shaded region in picture attached? Please suggest.
6. ### Value of Heat transfer coefficient

I have a circular cross-section of steel, around which I have air of constant temperature flowing. I want to calculate the heat flux, but I don't have the value of heat transfer coefficient,h (W/m^2.K) between steel and this air at 350C. Please suggest how to get the value for h. I am neglecting...
7. ### Transient Heat Transfer in Radial Direction

My geometry is bit complex. I want to make a heat transfer model based on FDM in the radial direction. But it has become very difficult to discretize the domain because of multiple materials. As the segments are symmetric, I want to model the heat transfer in one segment. My schematic is given...
8. ### Increasing Heat Transfer Area

I have an assembly where I'm using a starwound cable heater to heat up a flow of air. But the air is not heated to the desired temperature. So I have decided to increase the heat transfer area by using metallic wool or some meshing around the heater. can anybody plz suggest me which one would be...
9. ### Heat Transfer Estimation

I am working on a project involving this setup (please refer to the pic). Basically compressed air at a constant flow rate flows through a 1/4" tube to the tube shown and gets heated by the star-wound heater and, this hot air heats the small inner vessel and then leaves the system. Now I am...
10. ### Bolted flange Joints load calculation

I'm joining a flange and a cap using 9 bolts with a steel gasket placed in a 'o' ring. To ensure that the joint is leak proof, I need to calculate the load distribution in the area between two bolts for a given torque in the bolt[please refer to the figure, where the lines indicate the area...
11. ### Uncertainty analysis in aerofoil Help

Uncertainty analysis in aerofoil!! Help!! Homework Statement Wind tunnel experiment using a constant velocity to determine Cl, Cd and Cm at different angle of attack (-5, 0, 5, 10, 15) of a symmetric airfoil. Error analysis of the experimental investigation to asses uncertainties in Cd, Cl...
12. ### Error Analysis of Airfoil Experiment

I have done a wind tunnel experiment on NACA 0015 airfoil for different angle of attack at a fixed velocity. Also calculated Cp, Cl, Cd and Cm for each angle of attack. Now I want to do an error analysis to find uncertainties in Cl,Cd and Cm. Please explain how I'm going to do that? I have...
13. ### Airfoil pressure distribution

I need help to determine the angle theta at each point of the surface so that i can apply numerical integration to get the lift and drag using the pressure distribution. How can I define theta?
14. ### Automobile Superstructure

someone please explain the phrase "properties optimised for weight reduction" in case of auto body and spaceframes. Also please refer some links to some data on service conditions of auto body. Thanks in advance.