STEM Community Challenge Dr Steve Dorney 16 July 2011

2 Plan for today Background Bay House School/Vestas/ISVR – siting wind turbines ALNS/ISVR Consulting/Creative Partnerships – room acoustics The HESTEM “Project brief” document Have a go … Link to HESTEM curriculum change – environmental engineering consultancy Future: energy management; waste management

3 Locating a wind turbine Loci – see worksheet Applying technical, legal and social criteria Design and build at scale on school site + real-life example/issue - measurable but invisible impact on school/community - no legacy

4 Room acoustics 3 way project –Consulting experience for University students –Free professional assessment of spaces –Pupils involved in measurement, design and implementation

5 Four projects undertaken Investigation of Speech Intelligibility in The BLA Room The Hartley Library Investigation of the Acoustics of a Science Classroom Mayfield School, Portsmouth Noise Impact Assessment at a Proposed Skateboard Park Site Greatness Community Association Investigation of the Acoustics of a School Canteen Admiral Lord Nelson School, Portsmouth

6 ALNS Stage 1 – measure/report

7 ALNS Stage 2 – upgrade skills and knowledge

8 ALNS Stage 3 – design & test

9 ALNS Stage 4 – select, revise and implement

10 Room acoustics Broad range of maths and science Applying technical, legal and social criteria in tangible (audible!) scenario Realistic prototyping process + real-life example/issue + measurable and high impact on school/community + environmental and learning legacy

The sample HESTEM brief

Have a go … Time (s) Pressure (Pa) Decay is exponential Reverberation time: time for pressure to decay by a factor of 1000 (60dB) RT 60 = 3 x RT 20 If it’s too long …

The reverberation time of St Paul’s cathedral (at 500Hz) when empty of people is A.3 seconds B.7 seconds C.11 seconds D.15 seconds

A is the equivalent area of perfectly absorbing material (in m 2 ) The internal volume of St Paul’s Cathedral is 152,000m 3 and its reverberation time when empty of people is 11 seconds. Calculate: i.The equivalent absorption area when the cathedral is empty ii.The reverberation time when full (2000 people) where each person has an equivalent absorption area of 0.4m 2 Sabine’s formula

The reverberation time of St Paul’s cathedral (at 500Hz) when full of people is A.Less than 4 seconds B.Between 4 and 6 seconds C.Between 6 and 8 seconds D.Longer than 8 seconds

Predicting absorption area where  are absorption coefficients … Equivalent absorption area, Material Absorption coefficient,  Cost Carpet0.05£10 per m 2 Ceiling tile0.5£40 per m 2 Thick curtains0.35£7 per m 2 Linoleum0.02£2 per m 2 SeatingEquivalent absorption areaCost Plastic seats0.1m 2 each£20 each Upholstered seats0.8m 2 each£55 each

Challenge 2 The reverberation time of this room, if unfitted and unoccupied, would be 3 seconds, say. What is the most cost effective way of fitting it out (including 50 chairs) so as to halve the reverberation time (still unoccupied)? Challenge 3 Acoustic ceiling tiles are chosen as the sole solution to halve the reverberation time, and the headmaster needs to decide what proportion of the ceiling to have treated. Find an expression for the reverberation time as a function of cost and plot (sketch) the graph. Challenge 1 Estimate the volume of this room.

(for V=1350m 3 ) Of form

19 Plan for today Background – community/uni links via STEM? Bay House School/Vestas/ISVR – siting wind turbines ALNS/ISVR Consulting/Creative Partnerships – room acoustics The HESTEM “Project brief” document Have a go … Link to HESTEM curriculum change – environmental engineering consultancy Future: energy management; waste management