From ae41ff50c721b515d28c783806c42e3911bf4ba5 Mon Sep 17 00:00:00 2001 From: Danilo Ciliberti Date: Thu, 9 Apr 2020 12:40:34 +0200 Subject: [PATCH] Added gearbox option --- performanceCharts.m | 31 ++++++++++++++++++++++++------- 1 file changed, 24 insertions(+), 7 deletions(-) diff --git a/performanceCharts.m b/performanceCharts.m index 3b42960..ed6ab26 100644 --- a/performanceCharts.m +++ b/performanceCharts.m @@ -8,6 +8,7 @@ windSpeed = 20; % wind tunnel speed, m/s Jconv = windSpeed/propDiam*60; % J = V/nD = Jconv/RPM +% Plot labels % conditionLabels = {'Desired values','XROTOR','CFD','Wind tunnel'}; %%Operative points: Thrust (N), Shaft Power (W), RPM @@ -49,16 +50,32 @@ % 4.71 264.3 8621 % 5.56 318.4 9061]; -conditionLabels = {'DEP 20cm 8000','TIP 40cm 6000','TIP 40cm 4000','TIP 40cm 3000'}; +conditionLabels = {'DEP 20cm 8000','TIP 40cm 6000','TIP 40cm 4000','TIP 40cm 3000','TIP 40cm 2000'}; -condition{1} = [17.217 594.69 9549.3 - 9.0131 271.46 7639.4]; - +condition{1} = [14.00 467.88 8800]; condition{2} = [20.456 554.29 6366.2]; - condition{3} = [14.716 376.12 3819.7]; - condition{4} = [21.1 563.41 3183.1]; +condition{5} = [16.33 454.48 2000]; + +% Gearbox gear ratios, one per condition, used to gain torque at a lower +% speed, i.e. the motor moves the gearbox input shaft at higher rpm with a +% lower torque, while the propeller is linked to the output gearbox shaft, +% rotating at lower rpm with a higher torque. The power is obviuously the +% same, except for the mechanical losses of the gearbox. +% In this code we look at the motor. + +gratio = [1, 1, 3, 3, 4]; % gear ratio +gloss = [0, 0, 0.05, 0.05, 0.05]; % gearbox losses +for i = 1:numel(condition) + condition{i}(:,3) = condition{i}(:,3) .* gratio(i); + condition{i}(:,2) = condition{i}(:,2) .* (1+gloss(i)); +end + +% Update plot labels with gear ratio e gearbox losses +for i = 1:numel(condition) + conditionLabels{i} = [conditionLabels{i}, ' 1:',num2str(gratio(i))]; +end %% Lehner performance data v = 0; @@ -122,7 +139,7 @@ % Display a warning if no solution is found for the i-th condition % (i.e. the required performance is out of the motor map) if any(all(isnan(tempMat(:,4:6)),1)) - warning(['Cannot operate with: ',conditionLabels{i}]) + warning(['Outside motor map with ',conditionLabels{i}]) end end warning('on','backtrace')